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179 Cards in this Set
- Front
- Back
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What are the functions of the respiratory system?
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-Gas exchange between lung and blood (O2 in CO2 out)
-Moves air from the environment to the lungs and out (tidal flow) -Facilitates sense of smell (olfaction) -Facilitates sound production (phonation) |
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What named passageways and air tubes make up the conducting zone of the respiratory system? Why is it called “conducting”?
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Conducting Zone =Nares, Choanae, Pharynx, Larynx, trachea, bronchi, bronchioles. No gas exchange occurs in these areas, only for transporting air.
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What named air tubes make up the respiratory zone of the respiratory system? Why is it called “respiratory”?
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respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli
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Describe the external features of the nose (look in the mirror!)
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Dorsum = Bridge, Apex = tip, Ala = nostril walls
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Describe the internal structures that make up the framework of the nose. What is rhinoplasty?
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Septal cartilage: by tip
Greater Alar cartilage: covers front lateral walls of the nose lateral cartilage: sides of the bridge of the nose Rhinoplasy: size and shape of these cartilages rearranged |
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Know the boundaries of the nasal cavities (i.e., what is superior to it? What is inferior? What is posterior?). What are the names of the entrance (anterior) and exit (posterior) to the nasal cavities? What separates the left and right nasal cavities? How is this structure constructed? What are vibrissae?
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Vibrissae = nose hairs
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What are the names of the three conchae and meatuses? What are their functions? In what parts of the nasal cavities are they located? Why is the term “turbinate” sometimes used instead of concha? What tube opens into the inferior meatus?
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Superior, middle and inferior→ Chonchae increases the surface area and prosuces turbulence in airflow
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What are the names of the paranasal sinuses? Where are they located? What are some of their possible functions? Infection of the sinuses is called _____________?
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Frontal, maxillary
located in/around the ethmoid bone Possible Functions: Add surface area to nasal cavities Lighten the skull Add vocal resonance? |
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Give the anatomic classification (name) of the respiratory epithelium.
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Pseudostratified ciliated columnar epithelium with goblet cells
What are the two special features of this epithelium? |
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What are the two special features of this epithelium?
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nature's rubber cement+ Lamina propria and epitheluim capture things like dust and antigens in the sticky membrane
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What is the “mucous escalator” and why is it important to our health? How does cystic fibrosis affect the mucous escalator?
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The mucous escalator is the nasal cavity mucosa in which the cilia allows substances to travel down.
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What are the functions of the Naval Cavity Mucosa?
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Filters, warms, and humidifies air.
-Lamina propria contains lots of blood vessels & mucous/serous glands |
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Where is the nasopharynx located? What separates it from the oral cavity and oropharynx? What structure opens on its lateral wall?
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located in the superior portion of pharynx, behind the nasal cavities
Separated from the oropharynx by the soft palate the pharyngotympanic tube is on the later wall |
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Know the functions of the larynx. Where is the larynx located? Can it be located on the external surface of the neck? Which parts? Where on the neck can an “emergency airway” be opened?
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The organ of phonation (sound production) Note: Phonation= Speech
Regulates amount of air entering trachea and lungs. Acts as a valve to prevent food from entering the airway Thyroid (1) Cricoid (1) Epiglottis (1) Arytenoid (2) = 5 major cartilages |
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Know the named structures that make up the “skeleton” of the larynx. What are these structures made of? What is the epiglottis and where is it located? What tissue is it made of?
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All major cartilages are composed of hyaline cartilage EXCEPT the epiglottis = Elastic cartilage
Arytenoid cartilages are paired They are shaped like pyramids perched atop the cricoid cartilage |
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How are vocal folds different from vocal ligaments?
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Both extend from the thyroid cartilage (anterior) to the arytenoid cartilages (posterior).
Vocal ligament = An elastic membrane Vocal cord = Vocal ligament + mucous membrane covering it. |
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In what ways (directions) can the arytenoid cartilages be moved? Movement of the arytenoid cartilages can subsequently move the vocal folds in two anatomic directions – what are they? How do the movements of the folds affect volume of air moved?
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The arytenoid cartilages are able move in two ways: Rotation, Gliding
These movements can: Move cords together = Adduction; Move cords apart = Abduction |
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Contraction/relaxation of the laryngeal muscles (muscles of phonation) can affect the true vocal folds in four ways…. What are they? Are the muscles of the larynx smooth muscle or skeletal muscle? Which nerves supply these muscles? Is “phonation” the same thing as “speech”?
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Skeletal muscles innervated by the vagus nerves (via recurrent laryngeal nerves)
Perform 3 basic actions: Abduct the vocal cords. Adduct the vocal cords. Tense/relax the vocal cords. Posterior crico-arytenoid muscles: abduct vocal cord Lateral crico-arytenoid muscles:adduct the vocal cords Cricothyroid muscles: tense the vocal cords |
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Know the names of the first three orders of bronchi in the conducting zone.
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Hierarchy of major bronchi:
Main (primary) Lobar (secondary) Segmental (tertiary) |
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What supports the walls of the trachea and bronchi and prevents them from collapsing due to trauma or pressure?
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look up
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What is pleura? What are its named parts? What is the pleural sac?
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Pleura is a serous membrane:
Lining the inner body wall is parietal pleura. Lining the outside of the lungs is visceral pleura. The “potential space” between the two layers is the pleural cavity. |
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Be able to give a basic explanation of the mechanism of breathing (ventilation).
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Inspiration = Increase volume of thoracic cavity via external intercostal muscles and the diaphragm
Key concept = Parietal and visceral layers of pleura are move together Parietal pleura moves with body wall – visceral pleura follows it. Expiration = Passive recoil of body wall and lung tissue. The body wall and the lung tissues have LOTS of elastin. Example – anatomy of a bronchus. Note elastic fibers. |
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How does a pneumothorax prevent inspiration from happening?
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If the chest wail is compromised (e.g – penetrating wound) – air enters the pleural cavity = pneumothorax
Atmospheric air in the pleural cavity prevents the lung from expanding = lung collapses. |
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How is the lung hilum different from the lung root?
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Hilum = The depression in the organ where structures enter/exit.
Root = Collectively, the structures that enter/exit at the hilum |
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In terms of size, how are bronchioles defined?
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Air conducting tubes between 0.5 and 1mm in diameter
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Understand how the microanatomy of air tubes changes as one moves from bronchi to bronchioles to alveoli
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Cartilage in the trachea disappears around the end on the bronchi
smooth muscle is present in the entire ducts epithelium lowers after bronchioles and the cilia are not present on alveoli elastic fibers are in the walls of these air tubes |
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What exactly is an alveolus? What cell types are present in its wall, and what are their functions?
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Alveoli are air exchange bags.
Note that alveoli are constructed of a single layer of cells = Type I and Type II alveolar cells + a basal lamina with elastic fibers |
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What is a dust cell and what does it do?
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Dust cells are macrophages that live in alveoli. they eat poison.
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What is surfactant and why is it important? How is surfactant related to breathing problems in premature babies?
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Type II cells produce surfactant – this lowers surface tension in alveolus cavity – prevents alveoli from collapsing.
Premature babies don’t produce enough surfactant – that’s why they have difficulties surviving if born earlier than 25 weeks. |
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Know the three layers that make up the respiratory membrane? What phenomenon occurs at this membrane?
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Only 0.5 um thick!!
Respiratory membrane = Alveolar type I cell + Basal lamina + Endothelial cell of capillary = Easy passage for CO2 and O2 |
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Know the organs that make up the urinary system
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Kidneys
Ureters Urinary bladder Urethra |
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Know the major functions of the kidneys
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Excrete toxic compounds
-Nitrogenous wastes (urea, uric acid, & creatinine). -Other toxins & drugs. Maintain H20 & electrolyte balances in tissue fluids -Conserves H20 & produces concentrated urine. -Remove excess H20 when needed. -Regulate electrolyte concentrations (Na+, K+, Ca++, Mg++, Cl-) -Acid-base balance (H+ and HCO3-) Maintain blood pressure (secrete the enzyme renin). |
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renal filtration
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Glomerular filtration is the starting point for urine formation.
180 liters of filtrate is formed per day – however only ~ 1% is actually excreted. |
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reabsorption
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Kidneys cleanse the blood via the process of reabsorption
Filtrate is forced out of the blood in the kidneys –it not only contains the “bad” stuff – but some “goodies” as well that will need to be “reclaimed” = REABSORBED Tubular reabsorption & tubular secretion are the “fine tuning” of urine production |
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Be able to describe the gross location of the kidneys
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The kidneys are posterior to the peritoneum = retroperitoneal
Top of kidneys = T-11/T-12 Bottom of kidneys ~ L-3 |
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Be able to describe the external and internal gross features of the kidneys
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renal hilum= where the blood vessels and urethra enters
Renal sinus= a space inside – have to pass into the hilum first to get enter the sinus Internal anatomy: cortex, renal columns, renal pyramids, papilla, major/minor calyces, and renal pelvis |
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Define uriniferous tubule. What are its two major parts?
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Basic functional unit of kidney = Uriniferous tubule
Two parts of the U-tubule: -Nephron -Collecting duct |
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Know the parts that make up the nephron
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Distal convoluted tubule: transfers urine to the collecting duct
Loop of Henle Proximal convoluted tubule Renal corpuscle: Bowman's Capsule and glomerulus |
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What is a renal corpuscle? Know which artery enters and which artery leaves the renal corpuscle
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Renal corpuscle = Glomerulus + Glomerular capsule
Glomerular capsule (aka – Bowman’s capsule) a double-walled cup that surrounds the glomerulus The glomerulus is a tuft of fenestrated capillaries efferent and afferent arterioles enter/exit this area |
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What are medullary rays? Which parts of the uriniferous tubules makes them up?
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Bundles of collecting ducts are grossly visible as medullary rays
Collecting ducts drain urine into the minor calyces at the renal papillae |
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Know the functions associated with these circulatory structures: glomerulus and peritubular capillary bed
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Glomerulus: Capillary tuft where glomerular filtration occurs
peritubular capillary bed: Cling to the convoluted tubules – adapted for reabsorption and secretion |
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Glomerular Capsule
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Receives the filtrate of blood from the glomerulus
Filtrate = Same stuff as tissue fluid that bathes the cells of the body |
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Proximal convoluted tubule
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Major function = Tubular reabsorption
-Examples = sodium, chloride, H20 and glucose are reabsorbed and re-enter the blood in the peritubular capillaries Some secretion is also done here = e.g. Creatinine and some drugs are removed from the blood and transferred to the filtrate. |
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Loop of the nephron (Loop of Henle)
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Plays role in concentrating urine
Na out of loop into the tissue spaces between uriniferous tubules high concentration of Na (stippled areas) allows water to be removed from collecting ducts later. Ability to form a concentrated urine is an important adaptation to terrestrial environment for mammals |
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Distal convoluted tubule
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Secretion: Hydrogen and bicarbonate ions moved from blood to the DCT – helps regulate pH of urine.
Adjustable absorption of sodium & H20 if blood pressure gets too low |
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Direction of urine filtrate
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Blood: Glomerular capsule-> Proximal Convoluted Tubule-> Loop of Henle -> Distal Convoluted Tubule -> Collecting ducts
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Types of nephrons
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Cortical nephrons (85% of nephrons)
Juxtamedullary nephrons (15%) Note – nearly all of the parts of the nephrons are in the cortex – only the loops of Henle dip into the medulla (+ collecting ducts) |
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With respect to the entire nephron, where is the juxtaglomerular apparatus (JGA) located? Cells from which two structures make up the JGA?
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An area of specialized contact between distal convoluted tubule (DCT) and afferent arteriole (AA) -->JGA has cells of BOTH DCT & AA.
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What is the overall function of the JGA? Which hormone is involved? (it’s secreted by special cells in the JGA)
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2 parts of the JGA: Smooth muscle cells of the afferent arteriole & Distal convoluted tubule (DCT) cells near the afferent arteriole
AA cells detect low blood pressure -->secrete renin into blood--> sodium reabsorbed from urine into blood --> blood pressure increases. DCT cells detect high concentrations of sodium in urine --> signal AA cells to produce renin --> sodium reabsorbed from DCT to blood-->blood pressure increases |
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antidiuretic hormone (ADH)
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-hormone from pituitary
-increases the permeability of collecting duct walls to water. Booze inhibits ADH secretion from the brain -> Produces diuresis (H20 remains in duct = dilute urine) |
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Direction of urine filtrate
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Blood: Glomerular capsule-> Proximal Convoluted Tubule-> Loop of Henle -> Distal Convoluted Tubule -> Collecting ducts
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Types of nephrons
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Cortical nephrons (85% of nephrons)
Juxtamedullary nephrons (15%) Note – nearly all of the parts of the nephrons are in the cortex – only the loops of Henle dip into the medulla (+ collecting ducts) |
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With respect to the entire nephron, where is the juxtaglomerular apparatus (JGA) located? Cells from which two structures make up the JGA?
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An area of specialized contact between distal convoluted tubule (DCT) and afferent arteriole (AA) -->JGA has cells of BOTH DCT & AA.
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What is the overall function of the JGA? Which hormone is involved? (it’s secreted by special cells in the JGA)
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2 parts of the JGA: Smooth muscle cells of the afferent arteriole & Distal convoluted tubule (DCT) cells near the afferent arteriole
AA cells detect low blood pressure -->secrete renin into blood--> sodium reabsorbed from urine into blood --> blood pressure increases. DCT cells detect high concentrations of sodium in urine --> signal AA cells to produce renin --> sodium reabsorbed from DCT to blood-->blood pressure increases |
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antidiuretic hormone (ADH)
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-hormone from pituitary
-increases the permeability of collecting duct walls to water. Booze inhibits ADH secretion from the brain -> Produces diuresis (H20 remains in duct = dilute urine) |
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Review the parts of the nephron that are involved in the physiological processes of glomerular filtration, secretion and reabsorption
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FILTRATION: Blood -> Bowman’s capsule
SECRETION: Blood -> Nephron tubules RE-ABSORPTION: Nephron tubules -> Blood Excretion (urine) = Filtration (plus) secretion (minus) reabsorption |
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epithelial layer of the glomerular capsule
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Outer layer = Simple squamous epithelium
Inner layer = special cells called podocytes. Surround capillaries of glomerulus Capsular space = between outer & inner layers – receives the blood filtrate |
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Microscopic structure of the glomerular structure
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The inner layer of the glomerular capsule is formed by bizarre cells called podocytes that cling to the surfaces of the glomerular capillaries
Adjacent podocytes have interdigitating foot processes (pedicels) – between which are filtration slits (~ 40 nm wide!!) |
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Know the microanatomy of the “tubular” parts of the uriniferous tubule
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the filtration barrier contains 3 layers
1. Capillary endothelium 2. Basal lamina 3. Slit diaphragm that covers the filtration slits |
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microanatomy of proximal convoluted tubule
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-Lined by a simple cuboidal epithelium
Features of epithelial cells -Lots of mitochondria in basal cytoplasm -Microvilli on apical surfaces -Folded lateral and basal cell membranes Brush border (produced by many microvilli). |
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Review the parts of the nephron that are involved in the physiological processes of glomerular filtration, secretion and reabsorption
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FILTRATION: Blood -> Bowman’s capsule
SECRETION: Blood -> Nephron tubules RE-ABSORPTION: Nephron tubules -> Blood Excretion (urine) = Filtration (plus) secretion (minus) reabsorption |
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epithelial layer of the glomerular capsule
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Outer layer = Simple squamous epithelium
Inner layer = special cells called podocytes. Surround capillaries of glomerulus Capsular space = between outer & inner layers – receives the blood filtrate |
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Microscopic structure of the glomerular structure
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The inner layer of the glomerular capsule is formed by bizarre cells called podocytes that cling to the surfaces of the glomerular capillaries
Adjacent podocytes have interdigitating foot processes (pedicels) – between which are filtration slits (~ 40 nm wide!!) |
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Know the microanatomy of the “tubular” parts of the uriniferous tubule
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the filtration barrier contains 3 layers
1. Capillary endothelium 2. Basal lamina 3. Slit diaphragm that covers the filtration slits |
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microanatomy of proximal convoluted tubule
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-Lined by a simple cuboidal epithelium
Features of epithelial cells -Lots of mitochondria in basal cytoplasm -Microvilli on apical surfaces -Folded lateral and basal cell membranes |
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Thin portion of loop of nephron (Loop of Henle)
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Lined by a simple squamous epithelium
The thin ascending portion of the loop of Henle actively pumps chloride ions (and passively moves sodium ions) from the loop lumen into the connective tissue surrounding the nephron. The thin ascending portion of the loop is not permeable to water. This sets up a highly hypertonic environment in the connective tissue surrounding the nephron that will cause water to be moved out of the collecting ducts – this helps us (1) conserve water in our bodies and (2) produce a concentrated urine. |
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microanatomy of the distal convoluted tubule
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Lined by a simple cuboidal epithelium
Features of epithelial cells: Fewer microvilli-> no brush border, Fewer mitochondria, Folded lateral and basal cell membrane |
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Microanatomy of the collecting ducts
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Lined by a simple cuboidal epithelium
Epithelial cell features: Pale color = Few organelles & few mitochondria |
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Once the renal artery enters the kidney, know the three named orders of branching arteries that supply the kidney
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Renal artery->interlobar artery in renal column->arcuate artery -->interlobar artery in cortex
Interlobular arteries give rise to the afferent arterioles that supply the glomeruli |
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Describe the course of the ureter
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Convey urine from the kidneys to the urinary bladder in the pelvic cavity
2 to 3 major calyces converge to form the pelvis of the ureter they are retroperitoneal The narrowest portion of the ureters are the: Just distal to the pelvis of the ureter, As the ureters cross the external iliac arteries (they are compressed by the intestines), As they enter the wall of the urinary bladder |
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Thin portion of loop of nephron (Loop of Henle)
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Lined by a simple squamous epithelium
The thin ascending portion of the loop of Henle actively pumps chloride ions (and passively moves sodium ions) from the loop lumen into the connective tissue surrounding the nephron. The thin ascending portion of the loop is not permeable to water. This sets up a highly hypertonic environment in the connective tissue surrounding the nephron that will cause water to be moved out of the collecting ducts – this helps us (1) conserve water in our bodies and (2) produce a concentrated urine. |
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microanatomy of the distal convoluted tubule
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Lined by a simple cuboidal epithelium
Features of epithelial cells: Fewer microvilli-> no brush border, Fewer mitochondria, Folded lateral and basal cell membrane |
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Microanatomy of the collecting ducts
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Lined by a simple cuboidal epithelium
Epithelial cell features: Pale color = Few organelles & few mitochondria |
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Once the renal artery enters the kidney, know the three named orders of branching arteries that supply the kidney
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Renal artery->interlobar artery in renal column->arcuate artery -->interlobar artery in cortex
Interlobular arteries give rise to the afferent arterioles that supply the glomeruli |
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Describe the course of the ureter
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Convey urine from the kidneys to the urinary bladder in the pelvic cavity
2 to 3 major calyces converge to form the pelvis of the ureter they are retroperitoneal The narrowest portion of the ureters are the: Just distal to the pelvis of the ureter, As the ureters cross the external iliac arteries (they are compressed by the intestines), As they enter the wall of the urinary bladder |
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What are kidney stones
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Narrow parts of ureters are likely spots for kidney stones to lodge
Kidney stones are hard masses formed within the urine made from crystals of calcium oxalate, calcium phosphate, or uric acid. Large stones cause smooth muscle spasm in ureters |
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urinary bladder
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-An empty bladder resembles a pyramid with its apex pointing toward the abdominal wall
-A full bladder can rise as high as the umbilicus |
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What is transitional epithelium, where is it found, and what are its functions
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Transitional epithelium lines the urinary organs from the calyces in the kidney to the urinary bladder
Allows organs to stretch and fill. Prevents movement of water into organs Prevents urea from seeping out of the organs |
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What is the urethra? What is its function? Know its general course in males and females and where it terminates in both sexes
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Function: pathway from bladder to outside the body
Female = Short - Opens into vestibule anterior to vagina Male = Long – 3 named parts (prostatic, membranous & spongy). Opens at tip of glans penis. |
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What are kidney stones
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Narrow parts of ureters are likely spots for kidney stones to lodge
Kidney stones are hard masses formed within the urine made from crystals of calcium oxalate, calcium phosphate, or uric acid. Large stones cause smooth muscle spasm in ureters |
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urinary bladder
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-An empty bladder resembles a pyramid with its apex pointing toward the abdominal wall
-A full bladder can rise as high as the umbilicus |
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What is transitional epithelium, where is it found, and what are its functions
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Transitional epithelium lines the urinary organs from the calyces in the kidney to the urinary bladder
Allows organs to stretch and fill. Prevents movement of water into organs Prevents urea from seeping out of the organs |
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What is the urethra? What is its function? Know its general course in males and females and where it terminates in both sexes
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Function: pathway from bladder to outside the body
Female = Short - Opens into vestibule anterior to vagina Male = Long – 3 named parts (prostatic, membranous & spongy). Opens at tip of glans penis. |
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Know the organs/structures that make up the internal and external genitalia of males and females. Know the names of the male & female gonads
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Internal genitalia
-Within the pelvic cavity (e.g. –vagina, uterus, prostate). External genitalia -Outside the pelvic cavity, in an area called the perineum (e.g. - penis, testes, clitoris). Perineum = The most inferior portion of the trunk, located between the thighs and buttocks Gonads -Produce the sex cells (gametes). -Manufacture & secrete sex hormones Accessory sex organs -Tubes and glands. -Nourish, support & convey gametes |
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Gonads
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Testes
-Produce sex cells called sperm (spermatozoa) -Produce male sex hormones = testosterone Ovaries -Produce sex cells called ova (oocytes) -Produce female sex hormones = estrogen and progesterone |
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What is the scrotum? Why are the testes suspended outside the body cavity? What is the dartos?
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Body temp would render male infertile – sperm require cooler temps to mature
Housed OUTSIDE the pelvic cavity in a sac called the scrotum -Scrotum = A sac composed of skin and connective tissue (dartos) -Dartos contains smooth muscle that wrinkles the skin of the scrotum to conserve heat. |
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What are seminiferous tubules and what is their function? Where are they located?
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Sperm are produced in the testes within hundreds of coiled tubes called seminiferous tubules
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Know the names and locations of the sperm and semen conducting tubes. What is the difference between sperm and semen?
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Sperm mature in the epididymis
-The epididymis is a single highly coiled and tightly packed tube – if stretched out it would measure ~ 20 feet Sperm conducting tubes -The ductus deferens (vas deferens) transports sperm from the epididymis to the prostate (not directly to the penis!) Ductus deferens is about 18 inches long Ejaculatory ducts: Transmit sperm to the urethra - Formed by the union of the ductus deferens and the duct of the seminal vesicles Seminal vesicles = Tightly coiled blind-ended tubes |
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What is the spermatic cord?
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A cord made of connective tissue, blood vessels and the ductus deferens – suspends the testes and connects them to the body wall.
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Semen
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Sperm mass from the testes + secretions from:
Seminal vesicles Prostate Bulbo-urethral glands Ejaculation = Ejection of semen from the urethra at the external urethral orifice. 2 – 5 ml of semen per ejaculation = only about 1% is sperm -About 300 million sperm per ejaculation |
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Contents of the spermatic cord
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- Ductus deferens
- Testicular artery - Pampiniform plexus of veins - Lymphatic vessels - Autonomic nerves Pampiniform plexus of veins surrounds the testicular artery – cools the blood before it reaches the testes |
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Where is the inguinal canal located? What are the names of its two openings and where are these openings located? What does the canal contain in males?
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It is bounded by two “rings”-> deep inguinal ring and superficial ring
An opening in the abdominal wall that allows the passage of the spermatic cord between scrotum and pelvic cavity (female inguinal canals are mainly empty) |
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What is a hernia (in general)? Specifically, what is an inguinal hernia? Why are males prone to having these types of hernias?
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-A hernia is the abnormal protrusion of an organ or structure through an opening
-Because of the inguinal canal, the groin region is a potential weak area of the anterior abdominal wall in males -This is an example of an indirect inguinal hernia – that entered the deep ring, passed through the inguinal canal, left the superficial ring, and entered the scrotum |
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Name the arteries/veins that supply the male and female gonads.
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-Testicular a. & v.
-Ovarian a. & v. Why are they so long?? Development of course! Ovaries and testes descend during development. Testes descend into the scrotum. Undescended testes = Cryptorchidism |
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What are the two general cell types found in the epithelium of the seminiferous tubules?
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Cells are of two types:
-Spermatogenic cells = sperm-forming cells -Supporting cells |
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What is spermatogenesis? Know how the developing sperm are arranged in the walls of the seminiferous tubules
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These cells are in the process of becoming mature sperm = spermatogenesis, Takes about 75 days
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Spermiogenesis
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The final step in spermatogenesis
Spermiogenesis is the transformation of spermatids into spermatozoa takes ~ 2 months |
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What are Sertoli cells? What are their functions? Be able to explain why there is a blood-testis barrier.
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Supporting cells in seminiferous tubules
Physical support for developing sperm. Nourish sperm. Phagocytic. Produce testicular fluid = flush sperm out of seminiferous tubules into epididymis They also form the blood-testis barrier = tight junctions between Sertoli cells prevents escape of sperm proteins (antigens) = no autoimmune destruction of sperm. |
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Where are Leydig cells (interstitial cells) located? What do they produce?
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Produce & secrete testosterone into the blood
Located between the seminiferous tubules |
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Micro-anatomy of epididymis
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Pseudostratified columnar epithelium with stereocilia = long microvilli
Immature sperm hang around in the epididymis for ~ 20 days Leave as mature sperm. Slow passage of sperm through epididymis is crucial to their final maturity Principal cells: Secrete protein that allow sperm to swim (motility). Absorb excess testicular fluid |
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Stereocilia
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Stereocilia do not move – they are long microvilli that contact sperm to slow them down and allow the principal cells to do their things more efficiently
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How would you describe the microanatomy of the ductus deferens? What division of the nervous system supplies the ductus deferens?
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Small lumen, 3 thick smooth muscle layers – Propel sperm toward the ejaculatory duct = Sympathetic innervation
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How is a vasectomy performed? Why is it performed?
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A form of male sterilization
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Where are the seminal vesicles located and what do they produce?
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Located posterior to the bladder & superior to prostate
Tightly coiled, blind-ended tube with highly folded mucosa Seminal fluid: Makes up 60-70% of semen Contains fructose, prostaglandins & clotting proteins (makes semen viscous & sticky). Alkaline -> neutralizes acid conditions in the female genital tract |
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Know the location and function of the prostate. What is benign prostatic hyperplasia (BPH)? What is PSA? How is the prostate physically examined?
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Walnut-sized gland inferior to bladder
Prostatic fluid: 30-40% of semen. Contains citric acid and proteolytic enzymes (e.g. prostate specific antigen [PSA]) that liquefy semen. Gives semen its color. |
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Prostatic glands
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The prostate contains 30-50 compound tubulo-alveolar glands that empty independently into the urethra
There are tiny openings of the prostatic glands in the floor of the prostatic urethra |
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Clinical importance of the prostate
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-Enlarges as males age = Benign Prostatic Hyperplasia
-Prone to cancer (PSA enters blood – used to detect) -Examined “per rectum” (the “Urologist’s Handshake”). An enlarged prostate makes it difficult to urinate and prevents bladder from being completely emptied |
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Where are the bulbo-urethral glands located and what is their function?
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-Empty mucus into the spongy urethra.
-Produce “pre-ejaculate” that lubricates urethra and may neutralize its acid environment prior to ejaculation. |
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Know the gross features of the penis.
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Root = attached portion
Body = pendulous portion Contains 3 erectile bodies: --Corpora cavernosa (2) --Corpus spongiosum (1) |
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How does erection occur? (physiologically, that is!). What division of the nervous system is responsible for erection?
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The contraction of muscles DOES NOT cause erection, but does help support the erection
Cavernous bodies are modified veins with many cavities surrounded by an endothelium, connective tissue & smooth muscle. Small arteries dilate and fill the cavities with blood. Venous drainage is slowed = penis swells. Erection = Parasympathetic. Ejaculation = Sympathetic |
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Be able to name the parts of the female genital system (internal and external genitalia). How would you describe the organization of the female internal genitalia
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Gonads = Ovaries
-Note that ovaries are part of the female internal genitalia, while testes are part of male external genitalia Accessory sex organs -Uterus -Uterine (Fallopian) tubes -Vagina -External genitalia (labia, clitoris, etc.) |
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Give a definition of the broad ligament. What are its named parts? What is its function thought to be?
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The broad ligament supports the uterus, uterine tubes and ovaries
A double layer of peritoneum that drapes over the uterus and ovarian tubes and attaches to the ovaries. Has 3 named parts: Mesometrium (mm) Mesosalpinx (ms) Mesovarium (mo) Note that the mesovarian is oriented at a 90o angle to the other parts of the broad ligament – it projects posteriorly |
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Where are the ovaries located? What is their shape? What are their functions?
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Function = produces the eggs cells (ova) and sex hormones estrogen & progesterone
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Know the named parts of the uterine tubes (aka – Fallopian tubes). What is the function of the uterine tubes? How are the uterine tubes and the ovaries related anatomically?
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Fimbrae->ampulla->isthmus
ova enters through the infundibulum Function: location of conception and embryo travels down the tube into the uterus. |
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What is tubal ligation and what is its purpose
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Having the “tubes tied"
Permanent method of female sterilization |
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Define ectopic pregnancy. Where can these occur and what is the most common location?
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Most common location is in the wall of the uterine tube
pregnancy that stays in the uterine tube and growth of the fetus causes it to burst this is a medical emergency because of bleeding |
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Know the function and named parts of the uterus. What other organs are related to the uterus?
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The organ of gestation
Fundus, body, cervix, cervical canal, external os, and vagina |
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Position of the uterus
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The uterus is “normally” tipped forward on the vagina – this is called anteversion
The orientation of the uterus and vagina (when viewed in sagittal section) form the number “7” |
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How are the cervix (of the uterus) and vagina related? What is a Pap smear?
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A Pap smear is a sampling of epithelial cells from the cervix to check for abnormal changes in cell morphology
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Know the functions and the location of the vagina. What is the vaginal fornix (aka – posterior fornix) and why does it have potential clinical importance?
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Vagina
-Organ of copulation. -Birth canal. -Passes menstrual fluids Vaginal fornix (blind pouch) surrounds the cervix of uterus – note its proximity to the peritoneal cavity |
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Know the named parts of the female external genitalia (vulva). What is the perineum
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Mon pubis
Labia majora Labia minora Vestibule Clitoris The clitoris contains erectile tissue - it has a glans, a body and two crura Females also have erectile bodies surrounding the vestibule = Bulbs of vestibule Greater vestibular glands (Bartholin’s glands) – produce mucous to lubricate the vestibule |
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What does it mean when we say that pairs of structures are homologous? Know the homologous structures (male/female pairs) discussed in lecture.
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Penis=clitoris
scrotum=labia majora under surface of penis = labia minora bulbo-urethral gland = greater vestibular gland prostatic glands = urethral gland Homologous means that these pairs of structures have a common embryonic precursor structure |
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Know the locations/functions of the cortex & medulla regions of the ovary
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Medulla contains vessels, nerves, lymphatics
Cortex houses developing gametes = oocytes |
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What is a follicle in general? What are primordial follicles? Where in the ovary are primordial follicles located?
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Female sex cells are called oocytes.
Each oocyte is contained in a multicellular sac called a follicle. Girls are born with a supply of thousands of primitive structures called primordial follicles |
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What is the ovarian cycle?
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The menstrual cycle as it relates to the ovaries.
Each cycle lasts “on the average” one month. Three successive phases in cycle: -Follicular phase -Ovulation -Luteal phase FSH & LH from pituitary signal the ovary to begin the cycle->Begin ovarian cycle About 12 primordial follicles begin to mature->Only 1 primordial follicle will reach maturity by day 14 of the cycle and be ovulated and The others undergo atresia |
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Histology of follicle development
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1. Follicular cells start out squamous
2. Then become cuboidal 3. Then multiply to form stratified cuboidal epithelium – Follicular cells now called granulosa cells A layer of connective tissue (theca folliculi) surrounds follicle – Theca cells produce testosterone converted later into estrogen 4. Oocyte surrounded by glycoprotein layer (zona pellucida) and a fluid-filled antrum develops in the follicle 5. Antrum expands – oocyte & zona pellucida surrounded by layers of granulosa cells called corona radiata. Follicle now about 1 inch in diameter Only 1 primordial follicle makes it to this stage by day 14 of the ovarian cycle |
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Three phases of the ovarian cycle
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Follicular phase = Development of 1 mature follicle by Day 14 of cycle
-If no pregnancy then->Corpus albicans Luteal phase of cycle -Corpus luteum = Secretes progesterone Ovulation ~ Day 14 of cycle -Large surge in LH from pituitary |
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How does the lonely ovulated oocyte make its way into the uterine tube? What may happen if it doesn’t?
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An ovulated oocyte briefly enters the peritoneal cavity
Fimbriae of the uterine tube sweep the area around the ovary – causes currents in the peritoneal fluid that hopefully carry the ovulated ovum into uterine tube. |
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Describe the microanatomy of the uterine tube. Any special features?
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3 layers = serous membrane, smooth muscle, & mucosa
Ciliated simple columnar epithelium Highly folded mucosa maximizes contact with ovum (or zygote) + sperm |
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What are the three layers of the uterine wall?
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Perimetrium (peritoneum)
Myometrium (smooth muscle) Endometrium (A mucosa) -Simple columnar epithelium + lamina -The mucosa is regularly infolded to form uterine glands |
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Know the three named phases of the uterine (menstrual) cycle and how each phase affects the anatomy of the endometrium. Understand how the phases of the uterine cycle correlate with phases of the ovarian cycle
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-The menstrual cycle as it affects the endometrium of the uterus.
-Lasts “about” 1 month (same length of time as ovarian cycle). Three phases: -Proliferative phase -Secretory phase -Menstrual phase |
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Proliferative Phase
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Corresponds to follicular phase of ovarian cycle = Developing ovarian follicles secrete estrogen – stimulates build up of the endometrium after the last menstruation
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Secretory phase
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Glands secrete product rich in glycogen
Corresponds to luteal phase of ovarian cycle = Corpus luteum of ovary secretes progesterone – causes enlargement of epithelial cells and uterine glands + secretion of glands |
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Menstrual phase
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Progesterone secretion is halted.
Occurs if NO fertilized oocyte implants in the endometrium. Arteries to endometrium (spiral arteries) shut down – most of endometrium dies – then arteries open again and flood the endometrium with blood Dead endometrium is sloughed off with blood = a “period”. This part of endometrium deteriorates and is sloughed off All but the basal part of the endometrium is sloughed off. The basal endometrium is a platform for rebuilding of the endometrium and the spiral arteries Rebuilding signals the start of the next uterine cycle. |
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Microanatomy of the vagina
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Normally about 10 cm long and collapsed so that its walls touch
Note folds in vaginal mucosa (rugae) that allow vagina to be stretched Stratified squamous epithelium resists attack by bacteria and friction (e.g. - from intercourse) Lots of elastic fibers – allow vagina to be greatly distended (childbirth, intercourse) |
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What embryonic tissue layer gives rise to the breast? Where potentially can breasts develop in the human body? What are supernumerary nipples?
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Breasts are modified sweat glands.
They are derived from embryonic ectoderm. Puberty brings about growth due to influence of estrogen The mammary milk line is an ectoderm ridge along which breasts can develop nipples potentially can develop anywhere along the “milk line” |
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Know the external and internal anatomy of the breast
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Areola: pigmented area around nipple
nipple: center bump Bumps = Locations of areolar glands (sebaceous glands) Internal -The breast contains 15-20 independent glandular units called lobes. Lobes are compound alveolar glands -Lobes are made up of clusters of secretory sacs called lobules. Epithelial cells in lobules produce milk -Each lobe drains via a lactiferous duct. Each lactiferous duct opens independently on the nipple -Suspensory (Cooper’s) ligaments connect the glandular tissue to the skin’s dermis -Note: The subcutaneous fat determines the breast’s size and shape |
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What are myo-epithelial cells? What is their function?
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Myo-epithelial cells = specialized contractile cells (NOT muscle cells, but do contain actin & myosin) that squeeze milk from secretory cells in lobules.
-Influenced by hormone oxytocin |
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Be able to describe the basic anatomy of the breast in the female before puberty, during puberty (and after), and during pregnancy. What causes breasts to develop during puberty?
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Female = Before puberty (Male = Throughout life)
Lobes of breast are rudimentary with NO secretory cells. Female = Puberty: estrogen causes enlargement of breasts (fat deposition) – lactiferous ducts grow and branch – no lobules or secretory cells yet Pregnant female = Lobules develop with secretory cells during first trimester, but milk not produced until after baby delivered. -Pregnant female = Lobules develop with secretory cells during first trimester, but milk not produced until after baby delivered. |
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Where exactly is the breast located
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The breast is cone shaped. The apex is the nipple – the base overlies the body wall. Rib locations below refer to the base of the breast
Begins at the 2nd rib and attachment ends at the 6th spans from the sternum to the axilla -Note that the base of the breast overlies the pectoralis major and serratus anterior muscles. -A portion of the breast extends into the armpit = the axillary tail |
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Blood Supply of the Breast
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Lateral thoracic artery (from axillary artery)
Superficial branches of posterior intercostal arteries Perforating branches of internal thoracic artery |
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Lymph drainage of the breasts
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Lateral breast drains to axillary lymph nodes: ~ 75% of breast drainage to axillary nodes
Medial breast drains to parasternal lymph nodes: ~ 25% of breast drainage to parasternal nodes |
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Which cells of the lactiferous glands are affected by breast cancer? What is a radical mastectomy? Why is such an aggressive procedure performed?
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Most frequently diagnosed cancer in women – 2nd leading cause of death in women.
Affects duct cells of the lactiferous glands. May require removal of the affected breast = mastectomy. Radical mastectomy involves removal of breast, underlying muscles, and lymph nodes in an effort to remove all cancerous tissue. Cancer cells from the breast spread (metastasize) via lymph vessels through the muscles to the sentinel nodes of the breast = axillary lymph nodes and may spread to other organs. |
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Why is the placenta called a feto-maternal organ? What part of the blastocyst is involved in placenta development?
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From mother decidua = part of the endometrium of uterus.
From mother decidua = part of the endometrium of uterus. A feto-maternal organ The trophoblast is the part of the developing blastocyst that contributes to the placenta |
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What part of the uterus is involved in placenta development?
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endometrium is the mothers contribution to the placental development decidua
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What is human chorionic gonadotropin (hCG)? What cells manufacture it?
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The trophoblast makes a hormone – human chorionic gonadotropin (hCG) – this enters mom’s blood and ultimately mom’s urine. The presence of hCG is the basis for a positive pregnancy test.
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What is extra-embryonic mesoderm? Why is it important to placenta development?
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A new tissue layer develops = Extra-embryonic mesoderm (EEM).
The EEM develops between the “double bubble” and the cytotrophoblast. Important concept: Blood vessels that carry blood to/from the embryo develop within the EEM. During 2nd week – embryo is a bilaminar disc surrounded by two sacs = “double bubble” |
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Placental development
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The 2nd week is the week of twos
-Trophoblast differentiates into 2 layers -The Syncytiotrophoblast is digestive & invasive -Enzymes produced erode the endometrium = allowing the blastocyst to implant in wall of endometrium -A new tissue layer develops = Extra-embryonic mesoderm (EEM). -During 2nd week – embryo is a bilaminar disc surrounded by two sacs = “double bubble” -The EEM develops between the “double bubble” and the cytotrophoblast. Important concept: Blood vessels that carry blood to/from the embryo develop within the EEM |
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Chorionic Cavity
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Concept: Chorionic cavity physically separates the embryo (“double bubble”) from the tissues that will become the placenta (EEM + cytotrophoblast + syncytiotrophoblast).
-These 3 layers will give rise to the placenta A Connecting stalk develops from EEM |
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What are chorionic villi and why are they important?
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Many finger-like projections called chorionic villi are formed within the EEM, with embryo’s blood vessels in them
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What layers make up the placental membrane? Why is this membrane important?
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Layers
1. syncytiotrophoblast: Lacuna in syncytiotrophoblast = contains mom’s blood 2. Cytotrphoblast 3. Extra-embryonic mesoderm 4. Capillary Wall: Fetal capillaries in the villus of placenta Substances are exchanged between maternal blood & fetal blood across the placental membrane. Maternal blood and fetal blood never mix |
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What substances can cross the placental membrane?
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Yes
-Hormones Human chorionic gonadotropin from placenta – tells ovaries to keep making -progesterone = shows up in mom’s urine (pregnancy test). -Gases (O2, CO2, carbon monoxide). -Nutrients (sugars, amino acids, lipids). -Drugs & toxins (cocaine, nicotine, alcohol, urea) -Antibodies. -Viruses (rubella, measles). No -Large molecules & those with specific configurations/charges (insulin, heparin, bacteria). |
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Final development of the placenta
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Develops massive amounts of chorionic villi. Super efficient exchange of gases/nutrients/wastes
Later reduces its size – becomes “pancake-shaped” – occupies only a portion of the uterine wall – expelled from uterus after birth of child |
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how does the endocrine system regulate the other organ systems of the body
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Endocrine system = A system of ductless glands.
Endocrine glands secrete messenger molecules called hormones. Hormones enter the blood and travel to distant cells of the body = target cells. Hormones signal physiological responses in those cells work with chemical in the blood=slower the nervous system is faster =electrical |
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Know the names and general locations of the organs & tissues that make up the endocrine system
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most of the endocrine organs are in the midline of the body, maybe so the can equally control the right and left sides of the body
pineal gland, pituitary gland, hypothalamus, parathyroid glands, thymus gland, adrenal glands, pancreas, ovaries or testes. |
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What is the diffuse neuro-endocrine system (DNES)?
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Additional endocrine tissues:
Digestive tract & Respiratory tubes = Diffuse Neuro-endocrine system (DNES). a series of scattered cells in the body that participate in the endocrine system (ex. in GI tract) Includes entero-endocrine cells in the gut |
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Be able to describe the three methods whereby the release of hormones from endocrine glands are regulated
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humoral = monitoring blood levels
-ex. parathyroid gland monitors blood calcium levels neural = sympathetic nerve fibors stimulate cells to release hormones Hormonal = a hormone stimulates a hormone |
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Know the three general ways in which cells of endocrine glands are arranged, such that there is maximum contact between the cells and blood
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Concept: These arrangements maximize contact between cells and blood in capillaries.
1) Spheres-capillaries in between 2)straight cord- capillaries on the sides 3) networks: capillaries surrounding the networks |
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Where exactly is the hypophysis (pituitary) located? To what part of the brain is it attached and how is it attached?
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shaped like a gold club with the pituitary is the in sphenion bone and connected to the brain by a stalk called infundibulm and related to hypothalamus
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Describe the embryonic development/sources of the two parts of the hypophysis. Name these two parts of the hypophysis
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Adenohypophysis: front
-The adenohypophysis develops from an outpocketing of the oral cavity epithelium = The hypophyseal pouch (aka – Rathke’s pouch Neurohypophysis: back -The neurohypophysis develops from the neural tube = it is part of the diencephalon |
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The two divisions of the hypophysis you just described in the previous objective have several named subparts. Of these subparts, which two are the most active in producing or releasing hormones
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Pars distalis is part of the adenohypohysis and makes 7 different major hormones
Pars nervosa is part of the neuralhypohysis and makes 2 major hormones |
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Know the names and functions of the hormones produced in the pars distalis. In general, what are “tropic” hormones?
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makes protein hormone
Follicle-stimulating hormone*: targets gonads Lutenizing Hormone: targets gonads Thyroid stimulating Hormone*: targets cells in thyroid Prolactin: causes secretory cells in breast to produce milk Growth Hormone*; affects all cell, epiphyseal plates Adrenocorticotropic hormone: signals cells in the adrenal cortex “tropic” hormones they regulate endocrine cells in other parts of the body |
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pars distalis control
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the cell in the pars distalis are told to produce and secrete hormones by the hypothalamus
Note that neurons with cell bodies in the hypothalamus produce & secrete releasing hormones These hormones signal the release of hormones in the adenohypophysis these hormones spill into capillaries called the hypophyseal portal system |
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What is a portal system of veins
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Definition = Two capillary beds connected together by a vein(s).
Capillary bed # 1 receives blood from an artery->Primary capillary plexus (in hypothalamus),Receives blood from the superior hypophyseal artery Capillary bed # 2 drains its blood into a vein or veins. Secondary capillary plexus (in adenohypophysis); Blood leaves secondary plexus & enters blood stream to the body |
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What is the neurohypophysis and what hormones are released there? Where are these hormones actually produced?
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The neurohypophysis is part of the brain = Typical nervous tissue
-Anti-diuretic hormone (ADH) & Oxytocin made by hypothalamus are released into the blood system here Hormones are packaged in vesicles – move down axons to the pars nervosa Hormones enter capillary bed |
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How do the hypothalamus and the adenohypophysis communicate? In other words, are hormones released from the adenohypophysis independently, without the influence of other cells or chemical substances?
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1. Releasing hormones produced by neurons in hypothalamus
2. Releasing hormones travel to cells in adenohypophysis via portal veins 3. Hormones leave cells of adenohypophysis – enter venous blood and are distributed to the body |
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Know the location and blood supply of the thyroid gland
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located in the lower neck (NOT cartilage), has a let and right lobe connected by the isthmus crossing around the center cartilage ring of the trachea
blood supply by the superioir inferior thyroid veins--needs large blood supply because its and endocrone gland |
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Be able to discuss the microanatomy of the thyroid – e.g. – what cell types are present and what hormones do these cells produce?
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A follicle = Fundamental unit of the thyroid, hollow spheres with hollow centers formed by a single layer of cuboidal cells, only endocrine cell that stores a supply of it's hormones
COLLOID= The storage form of inactive thyroid hormone (called thyroglobulin) Follicle cells = Make precursor (thyroglobulin) & active thyroid hormone (TH) |
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What are the functions of the two hormones produced in the thyroid gland? Where is thyroid-stimulating hormone (TSH) produced and how does it influence the release of thyroid hormone (TH).
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Follicle cells of thyroid make thyroglobulin (inactive thyroid hormone) and store it in follicles where iodine is added. Stored product is called colloid.
Thyroid stimulating hormone (TSH) released from pars distalis of hypophysis. TSH taken up by follicle cells of thyroid. Follicle cells reclaim thyroglobulin & convert it into active thyroid hormone (TH), then release TH into the blood thyroid hormone increases basometabolic rate in cells, making ATP which maintains body temperature and |
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Where are the parathyroid glands located and how many are there? What hormone is produced here and what is its function?
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The parathyroid is located posterior and superior to the thyroid gland
Parathyroids produce parathyroid hormone Raises blood levels of calcium by stimulating the work of osteoclasts in bone Don’t confuse thyroid & parathyroid! They have different embryonic origins and different microscopic anatomy. |
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Parafollicular cells
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(a.k.a. – “C” cells) in the thyroid gland
Produce CALCITONIN A hormone that lowers blood levels of calcium by inhibiting the work of osteoclasts in bone. |
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Development of parathyroid glands
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Parathyroids (and the thymus) are derived from endoderm of the primitive pharynx called pharyngeal pouches – these are inside the pharyngeal arches of the embryo
Endodermal cells break away from pouches and migrate into neck & thorax calcatonin lowers blood levels of calcium and parathyroud hormone raises blood levels of calcium by stumilating osteoclasts |
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Development of the thyroid
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Foramen cecum of tongue is the site where thyroid began
Starts as a mass of endoderm from the pharynx at the site of the future tongue endoderm migrates into the neck After thyroid descends – the thyroglossal duct usually shrinks and closes |
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Where are the suprarenal glands located? Where are they with respect to the peritoneum? What are the two named parts of the suprarenal gland?
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Outer = cortex
Inner = medulla located retroperitoneal above the kidneys |
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Suprarenal medulla
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The cells are modified post-ganglionic sympathetic neurons
Secrete a class of hormones called catecholamines. Examples are epinephrine & norepinephrine The granules containing catecholamines are seen when stained with chromium salts. Thus these cells are also called chromaffin cells |
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Know the three named layers (zones) of the suprarenal cortex
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Zona glomerulosa (outer) - Produces mineralocorticoids like aldosterone
Zona fasciculata (middle) - Produces glucocorticoids such as cortisol and cortisone Zona reticularis (inner) - Produces glucocorticoids and androgens (male sex hormones) |
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What is the overarching function of hormones produced by suprarenal cortox. Are any “tropic” hormones involved in the release of hormones from the suprarenal cortex?
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The suprarenal cortex produces steroid hormones
Aldosterone – works on cells of the distal convoluted tubule in the kidney helps body retain sodium and water helps raise blood pressure and blood volume. Glucocorticoids (like cortisol) help body deal with stress maintains blood sugar at acceptable levels directs body to use lipids and amino acids for energy, thus sparing the blood sugar. Also helps reduce inflammation Adrenocorticotropic hormone (ACTH) released from hypophysis signals cells in the suprarenal cortex to release glucocorticoids |
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Steroid secreting endocrine cells vs. protein secreting endocrine cells
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Steroid secreting cells: Lots of SER & Lipid droplets (do not contain steroid hormones, but their building blocks)
Protein secreting: Lots of RER, Plenty o’ secretory granules, Well developed Golgi |
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Steroid hormone producing glands
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Suprarenal cortex
-aldosterone, cortisol, cortisone Gonads -Interstitial (Leydig) cells in testes (testosterone) -Theca cells & corpus luteum in ovaries (estrogen & progesterone ALL others produce protein hormones |
