Anatomy And Physiology Lecture #3

Front 1

What are functions of the kidney?

Back 1

Remove nitrogenous wastes (i.e. urea, creatinine, uric acid) or other organic wastes from blood.

Body Homeostasis: regulation of volume, blood pressure, composition, pH, osomolarity of blood; conserve nutrients (i.e. glucose, amino acids)

Front 2

What are the nitrogenous waste products that the kidney excretes?

Back 2

Urea, Creatinine and Uric Acid

Front 3

What is ureters?

Back 3

Transports urine towards the urinary bladder.

Front 4

What is the urinary bladder?

Back 4

Temporarily stores urine prior to elimination.

Front 5

What is the urethra?

Back 5

Conducts urine to exterior; connected to the urinary to the outside.

Front 6

What are the location of the cortex, medulla, pyramids and renal columns in the kidney?

Back 6

cortex: outer layer of the kidneys

medulla: the inner layer of the kidney

pyramid: triangle shaped structure or the medulla.

renal columns: Spaces between the pyramids

Front 7

What are functions of the collecting ducts?

Back 7

Receives filtrate from many nephrons.

Front 8

What is the pH in acidosis?

Back 8

Greater than 7.35

Front 9

What is the pH in alkalosis?

Back 9

Less than 7.45

Front 10

What are the three major buffering systems in the body?

Back 10

1. Chemical Buffer of the body fluids

2. Respiratory Buffering System

3. Renal Buffering System

Front 11

What are buffers?

Back 11

A substance that tends to oppose changes in the pH of a solution by removing or replacing hydrogen ions (in body fluid buffers maintain blood pH within normal limits).

Front 12

What are the three chemical buffering systems?

Back 12

1. protein buffering system

2. phosphate buffering system

3. bicarbonate buffering system

Front 13

Which chemical buffering is the most important inside cells?

Back 13

Protein buffering system is the most important of the buffer systems in cells.

Front 14

What is the importance of the bicarbonate buffering system and where does it work?

Back 14

Important because concentrations of HCO3- are high in ECF; especially plasma and PCO2 of blood can be regulated.

HCO3 concentrations are regulated by kidney

PCO2 is regulated by respiratory system

Front 15

How does the respiratory system help regulate that will help with buffering?

Back 15

the respiratory buffering system works by regulating the PCO2 (arterial partial pressures of carbon dioxide) of blood which affects plasma pH.

Front 16

What happens to blood H+ and pH when the respiratory rate increases?

Back 16

When CO2 increases, H+ increase and the blood pH decreases.

Front 17

What happens to blood H+ and pH when the respiratory rate decreases?

Back 17

When CO2 decreases, H+ decreases and the blood pH increases.

Front 18

Where are chemoreceptors located?

Back 18

Central: Medulla Oblongata of the Brain

Peripheral: Carotid Bodies and Aortic Bodies

Front 19

Why is the respiratory system unable to return pH to normal?

Back 19

The respiratory system cannot return pH to normal because it eventually loses the CO2/H+ stimuli.

Front 20

What is the slowest of the buffering systems to begin working?

Back 20

The renal buffering system is the slowest of the buffering systems to begin working.

Front 21

What buffering system is able to get pH back to normal?

Back 21

The renal buffering system is the most powerful buffering system; it can return pH to normal.

Front 22

What is normal pH of the urine?

Back 22

pH of 6; ranging form 4.5-8.0

Front 23

Within the kidney, what are the three buffering systems and which one removes the move H+?

Back 23

bicarbonate buffering system, phosphate buffering system and ammonia buffering system.

ammonia buffering system is the most powerful of the renal buffers because it removes 4H+

Front 24

Where in the kidney does the bicarbonate buffering system work?

Back 24

bicarbonate filtered into the kidneys binds to H+ secreted into the proximal tubule.

Front 25

How does the phosphate buffering system work and where does it work?

Back 25

Works in the proximal tubule, distal tubule and collecting ducts.

Front 26

Where does the ammonia chloride buffering work?

Back 26

in tubule cells proximal tubule, distal tubule and collecting duct; works when H+ persists.

Front 27

Where are some disturbances caused by acidosis (pH<7.35)?

Back 27

Depression of CNS, Disorietation and Coma

Front 28

Where are some disturbances caused by alkalosis (pH>7.45)?

Back 28

Overexcitability of the nervous system; PNS more than CNS, tetany (muscle contractions), convulsions.

Front 29

When there is an excess of H+, how do these imbalances influence the movement of ions in and out of the cells?

Back 29

acidosis: net movement of K+ out of the cells in exchange for H+ into the cell; H+ binds to protein buffers in the cells; cells becomes hyperpolarized due to loss of K+ (futher from the threshold and action potential)

Front 30

When there is a decreased in H+, how do these imbalances influence the movement of ions in and out of the cells?

Back 30

alkalosis: net movement of K+ into the cell in exchange for H+ out; cells become hypopolarized (closer to threshold and action potential)

Front 31

What is the two difference between cortical nephrons and juxtamedullary nephron?

Back 31

A. Cortical Nephron: 85%; small portion of loop goes into the medulla region.

B. Juxtamedullary Nephron: 15%; Bowman's capsule in cortex with distal tubule the loop is contained within the cortex.

Front 32

Which blood vessels make up the unique blood flow to the kidney?

Back 32

afferent arteriole> glomerular capillary> efferent arterioles> peritubular capillary> venule

Front 33

Which blood vessels send blood into the glomerulus? Collect blood from the glomerulus?

Back 33

Send: afferent arterioles

Collect: efferent arterioles

Front 34

What are the three steps of urine formation?

Back 34

1. glomerular filtration

2. tubular reabsorption

3. tubular secretion

Front 35

At what site in the kidney does filtration occur?

Back 35

Bowman's Capsule

Front 36

What happens during filtration?

Back 36

The movement of water, ions, and small molecules from blood int the glomerular capillary into Bowman's Capsule of the nephron.

Front 37

What are the characteristics of the glomerulus that effect filtration?

Back 37

permeability of glomerular capillaries

cross-sectional surface area (vessels/gram of tissue) of capillaries is large compared to capillaries in other organs/tissues.

Front 38

What is the glomerulus filtration rate? Daily urine output?

Back 38

GFR= 125 ml/min (180 l/day or 47.5 gal/day)

UO= 1-2 liters/day; approximately 1% of filtrate

Front 39

Whats is filtration? Reabsorption? Secretion?

Back 39

Filtration:

Front 40

In which portion of the nephron are the most water, ions and molecules reabsorbed?

Back 40

.

Front 41

What is the function of the urinary system?

Back 41

1. Excretion; removal of organic waste products from body fluid.

2. Elimination; discharging of these waste products into the environment.

3. Homeostatic Regulation of the volume and solute concentration of blood.

Front 42

What are the organs of the urinary system?

Back 42

two kidneys, two ureters, a urinary bladder and urethra.

Front 43

What is urine?

Back 43

A fluid that contains water, ions and small soluble compounds.

Front 44

What is the pathway of urine?

Back 44

Kidney> urinary tract (ureters)> urinary bladder> urethra.

Front 45

What is the function of the collecting ducts?

Back 45

Receive fluid from many nephrons. Beginning in the cortex and descends into the medulla, carrying fluid to a papillary duct to drain into a minor calyx.

Front 46

What are minor calyx?

Back 46

The ducts within each renal papilla which discharges urine. Shaped like a cup style structure.

Front 47

What are major calyx?

Back 47

Four or five minor calyces merging together.

Front 48

What types of nerves travel to the kidney and what do they do?

Back 48

The renal nerves innervate the kidney and ureters. They enter the kidney at the hilum and follows the branches of the renal arteries to reach individual nephrons.

Front 49

What does the sympathetic innervation do in the kidney?

Back 49

A. adjust rates of urine formation by changing blood floe and blood pressure at the nephron.

B. stimulates the release of renin. which ultimately restricts water and slat loss in the urine by stimulating the reabsorption by the nephron.

Front 50

What are the pressures in the glomerulus and Bowman's capsule that influence filtration?

Back 50

Glomerular Hydrostatic Pressure and Capsular Hydrostatic Pressure.

NHP= (GHP-CsHP)=(50 mmHg - 15 mmHg) = 35 mmHg

Front 51

What is the equation for the Net Filtration Pressure?

Back 51

NFP= (NHP-BCOP)=(35 mmHg-25 mmHg)= 10 mmHg

Front 52

Which pressure has the biggest effect on glomerular filtration?

Back 52

Blood pressure.

Front 53

What is filtration?

Back 53

blood pressure forces water ad solutes across the all of the glomerular capillaries and i to the capsular space. Solutes small enough to pass through the filtration membrane are carried by water molecules.

Front 54

What is reabsorption?

Back 54

Removal of water from and solutes from the filtrate. Moved across the tubular epitheium and into the peritubular fluid.

Front 55

What is secretion?

Back 55

Transport of solutes from that peritubular fluid. across the tubular epithelium and into the tubular fluid.

Tubular secretion; which removes substances from the blood, can further lower the plasma concentration of undesirable materials.

Front 56

In which portion of the nephron are the most water, ions and other molecules reabsorbed?

Back 56

Proximal Tubule

Front 57

What are some examples of substances reabsorbed or secreted in the proximal tubule? Which substance are reabsorbed by active transport? By passive transport?

Back 57

Reabsobed: vitamins, Na+, K+, H2O, Mg2+, PO43-,SO42-

Secreted: creatinine, penicillin, H+

Active: vitamins, Na+, K+, Mg2+, PO43-,SO42-

Passive: H20

Front 58

What does obligatory reabsorption water mean?

Back 58

Occurs in water permeable regions of the tubules in response to the osmotic gradient created by active Na+ transport.

Front 59

What is transport maximum and why does it occur?

Back 59

TM: The maximum amounts of substance transport per unit of time.

i.e. glucose 325 mmHg

Front 60

What is and is not reabsorbed in descending loop of Henle?

Back 60

Reabsorbs Na+, Cl-.

Permeable to water.

Front 61

What is and is not reabsorbed in ascending loop of Henle?

Back 61

Water impermeable.

Active transport of Na, Cl, K out of the thick ascending loop

Front 62

What is reabsorbed in the distal tubule?

Back 62

Variable reabsportion of H2O, Na+, Ca2+

Secretion of ions, acids, drugs, toxin

Front 63

How do aldosterone and antidiuretic hormone affect reabsorption in the distal tubule and collecting ducts?

Back 63

Aldosterone: increase Na+ channels (& rentention)

ADH: increase H2O channels (fluid reabsorption)

Front 64

Does strong sympathetic stimulation to the kidney decrease or increase GFR and urine output? Why?

Back 64

Strong sympathetic stimuli vasconstict afferent arteriole constriction afferent arteriole-----> increase GFR, decrease urine formation.

Front 65

What is autoregulation?

Back 65

maintains an adequate GFR despite changes in local blood pressure and blood flow.

Front 66

How does atrial natriuretic peptide/hormone affect glomerular filtration, renal blood flow, and urine output? When are these secreted?

Back 66

from the atria of heart. Decrease blood volume an blood pressure in response to stretch of the heart.

released due to stretch in the atrium.

Front 67

How do renin affect glomerular filtration, renal blood flow, and urine output? When are these secreted?

Back 67

A decrease in GRF leads to the release of renin b the juxaglomerular complex.

Front 68

What stimuli increase ADH secretion? Where does ADH work and what does it do?

Back 68

Osmorecptors in the hypothalmus. increase in osmoarity of blood = increase of ADH

works in the DT and CD in increasing the number of water channels.

Front 69

What stimuli decrease ADH secretion? Where does ADH work and what does it do?

Back 69

Osmorecptors in the hypothalmus. decrease in osmoarity of blood = decrease of ADH

works in the DT and CD in increasing the number of water channels.

Front 70

When ADH secretion increases, what happens to urine output? Why?

Back 70

increased ADH = increased water reaborption = decrease water in urine = decrease urine output

Front 71

What stimuli lead to the secretion of renin and what does renin do?

Back 71

decrease of GFR causes the release of renin from the juxaglomerular complex. Actives Ang II

Front 72

Where is angiotensin II formed and what are three functions of angiotensin II?

Back 72

Renin> activated protein angiotenungeous > Ang I> activates AngII by the ACE.

constricts peripheral arterioles and further consists the efferent arterioles; trigger increased aldosterone secretion by the adrenal gland; triggers neutral responses

Front 73

What stimulates aldosterone secretion and what does it do?

Back 73

increased ADH and increase blood volume

Front 74

What system establishes a hyperosmotic medulla in the kidney? What transporter is most important?

Back 74

The countercurrent multiper in the loop of Henle.

Active transport

Front 75

What are the water and ion permeability characteristics of the descending and ascending loop of Henle?

Back 75

D: thick, acts like PCT reaborbs Na+, Cl- out the of the Tubular fluid. Permeable to water

A: impermeable to water. thin: permeable to Na+ (diffuses to perticular fluid)

thick: actively transports Na+, Cl- , ions out of TF

Front 76

What conditions are necessary to produce a concentrated urine? a dilute urine?

Back 76

increase ADH= concentrated urine

decrease ADH= dilute urine

Front 77

What is diabetes insipidus and its symptoms?

Back 77

Lack of ADH; decrease to ADH

Symptoms: lose of large volume of dilution and increased thirst & an urge of to drink

Front 78

Where is erythropoietin made and secreted? What stimulates its secretion? What does it do?

Back 78

Made by interstital fibroblast in kidney.

Secreted from juxtagomerlar cells in the juxtagomeral apparatus of the kidney.

Released because of reduction in oxygen in the blood.

Stimulates the production RBCs

Front 79

What helps urine move through the ureters?

Back 79

perastalic contraction of smooth muscle moves urine through the ureters.

Front 80

What type of cells line the inside of the urinary bladder and ureters?

Back 80

UB: smooth muscle (detrasor muscle)

U: smooth muscle (longtudinal and circular layers)

Front 81

What type of muscle is found in the wall of the urinary bladder?

Back 81

transitional epithelium cells.

Front 82

What are rugae and when are they present?

Back 82

folds in the inferior of the mucous lines the urinary bladder and only present when bladder is empty.

Front 83

What is the trigone?

Back 83

triangular area bounded by the openings of the urters and the entrance to the urethra

Front 84

What forms the internal urethral sphincter and the external urethral sphincter, and where are these sphincters located?

Back 84

IUS: Smooth muscle; thicking of muscle in this area

EUS: skeletal muscle

located: the neck of the urinary bladder

Front 85

What does micturition mean?

Back 85

urination= emptying urinary bladder

Front 86

What is the stimulus for micturition reflex and what is the response to the micturition reflex?

Back 86

A. stretch of the urinary bladder

B. contract detrusor muscle of the bladder wall.

Front 87

What are the receptors, nerves, and order of events in a micturition reflex?

Back 87

stretch receptors, pelvis nerve p .12

Front 88

What are some problems of the urinary system seen with aging?

Back 88

decreased number of nephrons

decreased GFR

decreased reaponsiveness to hormone, ADH

Problem with micturtion reflex and voluntary control of urination