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178 Cards in this Set
- Front
- Back
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Tissue Types? (4)
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4 Types: Epithelial, Connective, Muscle, and Nervous
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Name the Primary Bones in the Skeletal System
Purpose? |
Provides protection and support, allows body movements, produces blood cells, and stores minerals and fat. Consists of bones, associated cartilages, ligaments, and joints.
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Name the Primary Muscles involved in the Muscular System
Purpose? |
Produces body movements, maintains, posture, and produces body heat. Consists of muscles attached to the skeleton by tendons.
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Name the primary systems involved in the Lymphatic System
Purpose? |
Removes foreign substances from the blood and lymph, combats disease, maintains tissue fluid balance, and absorbs fats from the digestive tract. Consists of the lymphatic vessels, lymph nodes, and other lymphatic organs.
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Name the primary organs in the respiratory system
Purpose? |
Exchanges oxygen and carbon dioxide between the blood and air and regulates blood pH. consists of the lungs and respiratory passages.
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Name the primary organs involved in the digestive system
Purpose? |
Performs the mechanical and chemical processes of digestion, absorption of nutrients, and elimination of wastes. Consists of the mouth, esophagus, stomach, intestines, and accessory organs.
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Name the main organs involved in the Nervous System
Purpose? |
A major regulatory system that detects sensations and controls movements, physiological processes, and intellectual functions. Consists of the brain, spinal cord, nerves, and sensory receptors.
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Name the primary organs in the Endocrine System
Purpose? |
A major regulatory system that influences metabolism, growth, reproduction, and many other functions. Consists of glands, such as the pituitary, that secrete hormones.
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Name the primary organs involved in the cardiovascular system
Purpose? |
Transports nutrients, waste products, gases, and hormones throughout the body; plays a role in the immune response and the regulation of body temperature. Consists of the heart, blood vessels, and blood.
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Name the primary organs involved in the Urinary System
Purpose? |
Removes Waste products from the blood and regulates blood pH, ion balance, and water balance. Consists of the kidneys, urinary bladder, and ducts that carry urine.
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Name the primary organs involved in the FEMALE reproductive system.
Purpose? |
Produces oocytes and is the site of fertilization and fetal development; produces milk for the newborn; produces hormones that influence sexual function and behaviors. Consists of the ovaries, vagina, uterus, mammary glands, and uterine tube.
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Name the primary organs involved in the MALE reproductive system.
Purpose? |
Produces and transfers sperm cells to the female and produces hormones that influence sexual functions and behaviors. Consists of the testes, ductus deferens, seminal vesicle, prostate gland, epididymis, and penis.
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Negative Feedback
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Negative feedback maintains homeostasis by resisting any deviation from set point and returning the body to a normal range.
1) A receptor monitors the value of a variable - blood pressure 2) Control center establishes the set point around the variable - brain 3) An effector changes the value of the variable to maintain homeostasis - heart Example: Blood Pressure |
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Positive Feedback
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Less Common than Negative Feedback
When a value deviates from normal values, the system's response is to make the deviation even greater Ex: inadequate delivery of blood to cardiac (heart) muscle Ex: hemorrhage = blood pressure goes decreases because of losing blood, heart can’t work properly (heart beats even slower), thus causing blood pressure to decrease even further, etc. Ex: Estrogen surge during menstrual cycle, release of estrogen causes more release of estrogen Negative feedback is much more common than positive feedback |
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ATP
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Adenosine Triphosphate
Provides energy as a result of breakdown from ATP → ADP |
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ECF
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Extracellular Fluid, makes up about 1/3 of the body's water
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ICF
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Intracellular Fluid, makes up about 2/3 of the body's water
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Interstitial Fluid
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Fluid that bathes the outside of cells, plasma leaks fluid into the interstitial space primarily through capillaries
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Capillaries
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the smallest of a body's blood vessels
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Plasma
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fluid part of the blood (extracellular)
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Diffusion? Basics?
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solutes move from a place of higher concentration to a place of lower concentration of that solute in solution.
Diffusion is random! Ex: perfume in a room WITH gradient Examples: Oxygen, carbon dioxide, chloride ions, urea Hydrophobic molecules diffuse easily across the cell membrane. Like diffuses like. Steroids are made of cholesterol (which is a lipid) therefore it diffuses across cell membranes. Ions DO NOT cross cell membranes |
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Net Diffusion?
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solutes move from a place of higher concentration to a place of lower concentration of that solute in solution.
Net Diffusion is HIGH → LOW Ex: More in "A" than in "B" |
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Osmosis
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Osmosis can be thought of as the diffusion of water from an area of high water concentration to an area of low water concentration. Water wants to move where it has more stuff to dissolve.
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Isotonic
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water plus salt (or a substance)
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Hypotonic
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it has more solute inside the cell than outside
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Hypertonic
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it has more solute outside of the cell than inside
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Facilitated diffusion
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Facilitated Diffusion utilizes a protein in the cell membrane to transport solutes down their concentration gradients.
Ex: glucose WITH gradient no energy needed |
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Primary Active Transport
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Primary Active Transport utilizes a protein to pump solutes against their concentration gradients. It moves low to high and requires additional energy (ATP).
Ex: Sodium out, Potassium in, ATP used up AGAINST gradient Ex: sodium, potassium, calcium, and hydrogen; amino acids |
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Secondary Active Transport
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Secondary Active Transport involves the coupled transport of 2 or more solutes.
It requires indirect energy, which comes from the primary active transport. Something is always moving in the gradient and something is always moving against the gradient; usually sodium is moving down. AGAINST gradient by carriers EX: Glucose, amino acids |
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Which direction is sodium pumped? Potassium?
Why is this important? |
Sodium moves Up
Potassium moves Down Results in a higher concentration of sodium extracellularly and a higher concentration of potassium intracellularly. This is essential in maintaining membrane potential. |
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Epithelium
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covers internal and external surfaces throughout the body. it also forms most glands.
No blood vessels in the epithelial tissue. Gets blood from the basement membrane. Purpose: protection, selective barrier, secretion, absorption, propulsion Identification: Open space |
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Basement Membrane
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Secreted partly by epithelial cells and partly by the cells of the underlying tissues. It consists of a meshwork of protein molecules with other molecules bound to them.
Has blood vessels Purpose: filter and barrier ex: prevent metastasis (moving of disease) Made of collagen and adhesives; acellular |
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Cilia
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propel materials along the free surface of cells. The nasal cavity and trachea are lined with pseudostratified columnar ciliated epithelium.
Require energy cuz they are constantly beating |
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Microvilli
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cylindrical extensions of the cell membrane that increase the free surface area. Normally many microvilli cover the free surface of each cell involved in absorption or secretion, such as the cells lining the small intestine or kidneys.
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Simple Squamous Epithelium
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Location: air sacs (alveoli) of lungs and inner linings of the heart and blood vessels
Purpose: Diffusion and Filtration - It is found lining surfaces of passive transport or gasses. |
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Simple Cuboidal Epithelium
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Location: Kidney tubules, thyroid gland, liver, and ducts of salivary glands
Function: Secretion, excretion, absorption |
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Simple Columnar Epithelium
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Location: Anywhere that requires absorption.
Nonciliated: uterus, stomach, and intestines. Ciliated: Uterine tubes Function: Protection, Secretion, and Absoption |
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Stratified Squamous Epithelium
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Location: Keratinized - Epidermis of the skin
Nonkeratinized - linings of the oral cavity, esophagus, vagina, and anal canal |
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Goblet Cells
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modified columnar epithelial cells that synthesize and secrete mucous
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Endocrine Glands
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No ducts
Empty secretions into the blood (Hormones) Includes: Thyroid gland and insulin-secreting portions of the pancreas |
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Connective Tissue
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found throughout body.
It is usually characterized by large amounts of extracellular material that separates cells from one another (Extracellular Matrix) Functions: Enclosing tissues, Support and movement, Energy storage, Cushioning and insulation, Protection |
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Extracellular Matrix
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Extracellular material that separates cells (connective Tissue).
Major Components: protein fibers, ground substance consisting of nonfibrous protein and other molecules and fluid |
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Exocrine Glands
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Have Ducts
simple or compound or tubular Includes: sweat glands and sebaceous glands |
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macrophages
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immune; white blood cells (phagocytes) that eat
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Compact Bone
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Locations: Bone Shafts (Sides of Bones), beneath periosteum
Functions: provides great strength and support and protects internal organs such as the brain, bone also provides attachment sites for muscles and ligaments |
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Spongy (Cancellous) Bone
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locations: ends of long bones; inside flat and irregular bones
Functions; holds marrow, provides strength and support |
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Do blood vessels extend into epithelium? How does epithelial tissue exchange gasses, nutrients and wastes?
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Blood vessels do not extend from the underlying tissues into epithelium, so gases and nutrients that reach the epithelium must diffuse across the basement membrane from the underlying tissues, where blood vessels are abundant. Waste products produced diffuse across the basement membrane to blood vessels.
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Are blood vessels present in connective tissue?
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yes, erythrocytes are generally present in connective tissue.
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How does collagen fiber help tissues?
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it provides added strength and durability.
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Muscle Tissue
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Characterized by elongated cells, often called muscle fibers, that can contract to create movements
Attached to skeleton, but also components of internal organs Generates body heat through movement |
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Skeletal Muscle Tissue
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Voluntary Control, Striated
Locations: Attached to bones via tendons, tongue, facial muscles, and voluntary sphincters Functions: body movement, maintaining posture, breathing, speaking, controlling waste eliminations, and protection |
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Smooth Muscle Tissue
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Involuntary, non-striated
Locations: visceral organs, the iris, blood vessels, respiratory tubes, attached to hair follicles Functions: visceral organs, controlling pupil size, blood flow, and airflow, and creating "goose bumps" if we are too cold or frieghtened |
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Cardiac Muscle Tissue
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Involuntary, Striated
Locations: Only in heart wall Functions: Pumping Blood |
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Neurons
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Contain a cell body with the nucleus and most of the cytoplasm, and cellular processes that extend from the cell body
Cellular processes include one to many dendrites and a single axon (nerve fiber) Functions: Considered excitable cells because they can exhibit signals called action potentials (nerve impulses) along the neuron to another neuron or a muscle or gland |
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Neuroglia
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Glial Cells
More abundant than neurons Cannot conduct nerve impulses Functions: they have important supportive and protective functions for neurons |
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Integumentary System
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Consists of the skin and accessory structures, such as hair, glands, and nails
Functions: Protection, sensation, vitamin d production, temperature, regulation, excretion |
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Epidermis
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most superficial layer of skin, layer of epithelial on the dermis, prevents water loss and resists abrasion, stratified squamous epithelium, new cells produced by mitosis.
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Dermis
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layer of dense connective tissue, on average the dermis is 10-20 times thicker than the epidermis, responsible for structural strength of skin, rests on hypodermis which connects skin to muscle
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Subcutaneous Fat
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a fat layer found in the hypodermis, the base layer of skin. It is connective tissue to muscle.
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Keratinization
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as new cells form, they push older cells to the surface, where they slough, or flake off. The outermost cells protect the cells underneath, and the deeper, replicating cells replace cells lost from the surface. During their movement, the cells change shape and chemical composition. The cells are filled with the protein keratin, which makes them hard. As keratinization proceeds, epithelial cells eventually die and produce an outer layer of dead, hard cells that resists abrasion and forms a permeability barrier.
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Stratum Corneum
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The most superficial stratum of the epidermis. it consists of dead squamous cells filled with keratin. Keratin gives the stratum corneum its structural strength. The stratum corneum cells are also coated and surrounded by lipids, which help prevent fluid loss through the skin. It consists of 25 or more layers of dead squamous cells joined by desmosomes. Excessive stratum corneum cells sloughed from the surface of the scalp are called dandruff. in skin subjected to friction, the number of layers in the stratum corneum greatly increases, producing a thickened area called a callus.
keratinocytes Apical Layer |
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Stratum basale
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deepest stratum, consists of cuboidal or columnar cells that undergo mitotic divisions about every 19 days. one daughter cell becomes a new stratum basale cell and can divide again. The other daughter cell is pushed toward the surface, a journey that takes about 40-56 days. As cells move to the surface, changes in the cells produce intermediate strata.
Made of cuboidal or columnar tissue. Takes almost 3 months to have all knew skin (reach surface) keratinocytes "Germinativum" Basal Layer |
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Mitosis
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when a cell undergoes self division into two different cells
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Dermal Papillae
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Contain many blood vessels that supply the overlying epidermis with nutrients, remove waste products, and help regulate body temperature. The dermal papillae int he palms of the hands, the soles of the feet and the tips of the digits are arranged in parallel, curving ridges that shape the overlying epidermis into fingerprints and footprints. The ridges increase friction and improve the grip of the hands and feet.
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Melanocytes
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melanin is produced by melanocytes, which are irregularly shaped cells with many long processes that extend between the epithelial cells of the deep part of the epidermis.
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Melanin
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"black", group of pigments primarily responsible for skin, hair, and eye color. Most melanin molecules are brown to black pigments, but some are yellowish or reddish. Melanin provides protection against ultraviolet light from the sun. Large amounts of melanin form freckles or moles in some regions of the skin, as well as darkened areas in the genitalia, the nipples and the circular areas around the nipples. Other areas, such as the lips, palms of the hands, and soles of the feet, contain less melanin. melanin production is determined by genetic factors exposure to light, and hormones.
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Hair follicle
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hair arises from a hair follicle, an extension of the epidermis that originates deep in the dermis. The shaft of hair protrudes above the surface of the skin, whereas the root and hair bulb are below the surface.
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Hair Bulb
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below the surface. hair is produced in the hair bulb, which rests on a dermal papilla. Blood vessels within the papilla supply the hair bulb with the nourishment needed to produce the hair. Hair is produced in cycles.
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Sabaceous glands
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simple, branched acinar glands. Most are connected by a duct to the superficial part of the hair follicle.
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Sebum
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an oily, white substance rich in lipids. The sebum lubricates the hair and the surface of the skin, which prevents drying and protects against some bacteria.
Exocrine |
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Apocrine Sweat Glands
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Simple, coiled, tubular glands, that produce a thick secretion rich in organic substances. They open into hair follicles, but only in the armpits and genitalia. Apocrine sweat glands become active at puberty because of the influence of sex hormones. The organic secretion, which is essentially odorless when released is quickly broken down by bacteria into substances responsible for what is commonly known as body odor.
Exocrine |
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Eccrine Sweat Glands
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simple, coiled, tubular glands located in almost every part of the skin but most numerous in the palms and soles. They produce a secretion that is mostly water with a few salts. Eccrine sweat glands have ducts that open onto the surface of the skin through sweat pores. When the body temperature starts to rise above normal levels, the sweat glands produce sweat, which evaporates and cools the body. Sweat can also be released in the palms, sole, armpits, and other replaces because of emotional stress. Emotional sweating is used in lie detector tests because sweat gland activity usually increases when a person tells a lie. Such tests can detect even small amounts of sweat because the salt solution conducts electricity and lowers the electrical resistance of the skin.
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Vitamin D
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formed when exposed to ultraviolet light. The vitamin is carried by the blood to the liver, where it is modified and then to the kidneys, where it is modified further to form active vitamin d. If exposed to enough ultraviolet light, humans can produce all the vitamin d they need. However many people need to ingest vitamin d as well because clothing and indoor living reduce their exposure to UV Light. Fatty fish and vitamin d fortified milk are the best sources. Vitamin d stimulates the intestines to absorb calcium and phosphate, the substance necessary for normal bone growth and normal muscle function.
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What are the major functions of the integumentary system?
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Protection
Sensation Vitamin D Production Temperature Regulation Excretion |
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What function is the epidermis best adapted for? The dermis?
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epidermis prevents water loss and resists abrasion.
dermis is responsible for most of the skin's structural strength. (collagen and elastic fibers) |
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Describe how skin grows? Which layers are involved? What is the role of keratinization?
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New cells are produced by mitosis. As new cells form, they push older cells tot he surface, where they slough, or flake off. The outermost cells underneath, and the deeper, replicating cells replace cells lost from the surface. During their movement, the cells change shape and chemical composition. The cells are filled with the protein keratin (keratinization), which makes them hard. As keratinization proceeds, epithelial cells eventualy die and produce an outer layer of dead, hard cells that resist abrasion and form a permeability barrier. Specific layers of strata are involved (Stratum Basale to Stratum Corneum).
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What kind of tissue is the dermis? What structures and cell types are present within the dermis? Are blood vessels present?
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The dermis is composed of dense collagenous connectie tissue containing fibroblasts, fat cells, and macrophages. nerves, hair follicles, smooth muscles, glands, and lymphatic vessels extend into the dermis Collagen and elastic fibers are responsible for the structural strength of the dermis.
Blood vessels are present. |
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How do epithelial cells in the skin acquire melanin? What factors account for skin color? Which of these increase melanin production?
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Factors that determine skin color include pigments in the skin, blood circulating through the skin, and the thickness of the stratum corneum. Melanin is the group of pigments primarily responsible for skin, hair, and eye color. melanin is produced by melanocytes which are irregularly shaped cells with many long processes that extend between the epithelial cells of the deep part of the epidermis. The Golgi apparatuses of the melanocytes package melanin into vesicles called malanosomes which move into the cell process of the melanocytes. Epithelial cells phagocytize the tips of the melanocyte cell processes, thereby acquiring melanosomes.
Melanin production is determined by genetic factors exposure to the light, and hormones. Exposure to ultraviolet light in sunlight stimulates melanocytes to increase melanin production. The result is a tan. |
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What is the role of the skin in vitamin D synthesis? Give one example why having adequate levels of vitamin D in the body is important.
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Adequate levels of vitamin D are necessary because vitamin D stimulates the intestines to absorb calcium and phosphate, the substances necessary for normal bone growth and normal muscle function.
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How is body temperature homeostasis regulated by blood flow in the skin?
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Normal body temperature is maintained at = 37 C
Regulation of body temperature is important because the rate of chemical reactions within the body can be increased or decreased by changes in the body temperature. Even slight changes in temperature can make enzymes operate less efficiently and disrupt the normal rates of chemical changes in the body. To cool, blood vessesl in the dermis dilate and enabel more blood to flow within the skin, thus transferring heat from deeper tissues to the skin where the heat is lost by radiation (infrared energy), convection (air movement), or conduction (direct contact with an object). Sweat that spreads over the surface of the skin and evaporates also carries away heat and reduces body temperature. To heat, constriction of dermal blood vessels reduce blood flow to the skin. Thus less heat is transferred from deeper structures to the skin, and heat loss is reduced. however with smaller amounts of warm blood flowing through the skin, the skin temperature decreases. if the skin temperature drops below 15 C, dermal blood vessels dilate. |
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Diaphysis
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Diaphysis = central shaft of the bone
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Epiphysis
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Epiphysis = ends of bone
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Red Marrow and Yellow Marrow
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Red marrow and Yellow Marrow – resides in medullary cavity in the diaphysis, and smaller cavities in the epiphyses of long bones.
Red marrow consists of blood-forming cells and is the only site of blood formation in adults. Children have more red marrow than adults (growth). Yellow marrow replaces red, it contains mostly adipose tissue. |
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Periosteum
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Periosteum – Most of the outer surface of bone is covered by dense connective tissue which is HIGHLY vascularized (blood vessels) and lots of nerves; outer layer is tougher
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Compact Bone
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Compact bone – blood vessels in bone matrix (osteons) are only found in compact bone; forms most of the diaphysis of long bones and the thinner surfaces of all other bones.
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Osteoblasts
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The periosteum and endosteum contain osteoblasts, which function in the formation of bone, as well as in the repair and remodeling of bone. When osteoblasts become surrounded by matrix, they are referred to as osteocytes.
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Osteocytes
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When osteoblasts become surrounded by matrix, they are referred to as Osteocytes.
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Spongy Bone (cancellous)
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consists of a lacy network of bone with many small marrow-filled spaces.
It is located mainly in the epiphyses of long bones. It forms the interior of all other bones. Spongy bone consists of delicate interconnecting rods or plates of bone call trabeculae, which resemble scaffolding, the trabeculae add strength to a bone without the added weight that would be present if the bone were solid mineralized matrix. The spaces between are filled with marrow. |
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Parathyroid Hormone
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PTH is secreted from the parathydoid glands when blood calcium levels are too low, stimulates increased bone breakdown and increased blood calcium levels by indirectly stimulating osteoclast activity. PTH increases calcium uptake from the urine in the kidney. Additionally, PTH stimulate the kidneys to form active vitamin D, which increases calcium absorption from the small intestine. Decreasing blood calcium levels stimulate PTH secretion.
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Synovial Fluid
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A complex mixture of polysaccharides, proteins, fat, and cells. Synovial fluid forms a thin, lubricating film covering the surfaces of the joint. In certain synovial joints, the synovial membrane many extend as a pocket or sac called a bursa.
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What are the major functions of the skeletal system?
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Support
Protection Movement Storage Blood Cell Production |
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What type of tissue is bone tissue? Describe the composition of the bone matrix. What would it be like if all of the mineral were removed? What if all of the collagen were removed?
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Bone is made up of either compact or spongy Bone. But mostly it consists of an extracellular Matrix.
Hydroxyapatite: bone mineral composed of calcium phosphate crystals (This is like the concrete) Collagen (like the flexible rebar) If all the mineral were removed it would be super flexible If all the collagen were removed it would be really rigid. |
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Describe how a long bone, such as the femur, would differ between a young person and an adult.
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Young:
Mostly Spongy Bone Tons of Red Marrow (for blood cell productions) Epiphyseal plates are not closed yet - still growing Adults; Mostly Compact (though there is Spongy) Mostly yellow marrow (used to hold fatty marow, for minerals) Epiphyseal Plates have closed now called the Epiphyseal Lines |
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How do growth hormone, estrogen and testosterone respectively affect bone growth?
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Growth Hormone stimulates lengthening of bone, endochondral ossification. It also stimulates bone widening. If you have an excess of growth hormone, as a child your bones would become taller, as an adult your bones would become wider (because your epiphyseal plates are closed).
Testosterone is needed to close the epiphyseal plates. Estrogen prevents bone resorption. |
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What important role does bone play in Ca homeostasis? How do parathyroid hormone and vitamin D affect Ca homeostasis?
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Bone is the major storage site for calcium int he body, and movement of calcium into and out of bone helps determine blood calcium levels, which is critical for normal muscle and nervous system function. Calcium moves into bone as osteoblasts build new bone and out of bone as osteoclasts break down bone. When blood calcium levels are too low, osteoclast activity increases, releasing calcium into blood. If blood calcium is too high, osteoclast activity decreases.
Parathyroid hormone (PTH) is released when calcium levels are too low in the blood. It stimulates bone breakdown and increased blood calcium levels by indirectly stimulating osteoclast activity. PTH also increases calcium uptake from the urine int he kidney. Additionally, PTH stimulates the kidneys to form active vitamin D, which increases calcium absorption from the small intestine. Decreasing blood calcium levels stimulate PTH secretion. Calcitonin is the hormone that decreases osteoclast activity. Calcium is important for muscle tissue and nervous tissue. |
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How do the three types of articulations differ? Provide an example for each.
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Fibrous: little or no movement; fetal skull
Cartilaginous: united by cartilage; epiphyseal plates, costal cartilage and intervertebral discs Synovial: free movement; joints of appendicular skeleton; filled with synovial fluid |
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Resting Membrane Potential
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The inside of most cell membranes is negatively charged compared to the outside of the cell membrane; in other words, the cell membrane is polarized. The charge difference, called the resting membrane potential, occurs because there is an uneven distribution of ions across the cell membrane. The resting membrane potential develops for three reasons; the concentration of K inside the cell membrane is higher than outside the cell membrane; the concentration of Na outside the cell membrane is higher than inside the cell membrane; and the cell membrane is more permeable to K than it is to Na.
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Action Potential
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The rapid depolarization and repolarization of the cell membrane is called an action potential. In a muscle fiber, an action potential results in muscle contraction.
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Depolarization & Repolarization
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Resting membrane potential = Na channels and some, but not all, K channels are closed. A few K diffuse down their concentration gradient through the open K channels, making the inside of the cell membrane negatively charged compared to the outside.
Depolarization = Na channels are open. A few Na diffuse down their concentration gradient through the open Na channels, making the inside of the cell membrane positively charged compared to the outside. Repolarization = Na channels are closed, and Na movement into the cells stops. More K channels open. K movement out of the cell increases, making the inside of the cell membrane negatively charged compared to the outside once again. |
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Motor Neurons
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Motor neurons are specialized nerve cells that stimulate muscles to contract. Motor neurons generate action potentials that travel to skeletal muscle fibers. Axons of these neurons enter muscles and send out branches to several muscle fibers.
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Neuromuscular Junction
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Axons of motor neurons enter muscles and send out branches to several muscle fibers. Each branch forms a junction with a muscle fiber, called a neuromuscular junction. A more general term, synapse, refers to the cell-to-cell junction between a nerve cell and either another nerve cell or an effector cell, such as a muscle or gland cell. Neuromuscular junctions are located near the center of a muscle fiber.
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Motor Unit
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A single motor neuron and all the skeletal muscle fibers it innervates constitute a motor unit. The fewer fiber there are in the motor units of a muscle, the greater control you have over that muscle. Many muscle units constitute a single muscle.
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Smooth Muscle Fibers
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Involuntary Control
Locations Walls of hollow organs Vasculature Bronchioles Iris and ciliary body in eyes Functions Under involuntary control Autonomic nervous system Produce motility Propel food in the GI tract Maintain tension Vascular tone |
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Motor Unit
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A single motor neuron and all the skeletal muscle fibers it innervates constitute a motor unit.
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Major functions of the muscular system?
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Movement
Posture Respiration Heat production Organ/vessel constriction Heart contraction |
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Describe how flow of ions lead to the resting membrane potential and the generation of action potentials
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Briefly describe the steps involved in synaptic transmission of an action potential across the neuromuscular junction
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Each presynaptic terminal (axon) contains many small vesicles, called synaptic vesicles. These vesicles contain acetylcholine, or ACh, which functions as a neurotransmitter, a molecule released by a presynaptic nerve cell that stimulates or inhibits a prostynaptic cell. When an action potential reaches the presynaptic terminal, it causes Ca channels to open. Ca enter the presynaptic terminal ancd cause several synaptic vesicles to release acetylcholine into the synaptic cleft by exocytosis. The acetylcholine diffuses across the synaptic cleft and binds to acetylcholine receptor sites on the Na channels in the muscle fiber cell membrane. The combination of acetylcholine with its receptor opens Na channels and therefore makes the cell membrane more permeable to Na. The resulting movement of Na into the muscle fiber initiates an action potential, which travels along the length of the muscle fiber and causes it to contract. The acetylcholine released into the synaptic cleft between the neuron and muscle fiber is rapidly broken down by an enzyme, acetylcholinesterase. This enzymatic breakdown ensures that one action potential in the neuron yields only one action potential in the skeletal muscle fibers of that motor unit and only one contraction of each muscle fiber.
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Where is smooth muscle found in the body? What are its functions?
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Locations
Walls of hollow organs Vasculature Bronchioles Iris and ciliary body in eyes Around Arteries and Blood vessels Functions Under involuntary control Autonomic nervous system Produce motility Propel food in the GI tract Maintain tension Vascular tone Helps maintain blood pressure (like sitting and standing) |
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Posterior (Dorsal)
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Closer to back of body
The teeth are posterior to the lips |
|
|
Medial
|
Closer to midline of body
The nose is medial to the eyes |
|
|
Lateral
|
Farther from midline of body
The eyes are lateral to the nose |
|
|
Intermediate
|
Between two structures
The elbow is intermediate between the shoulder and the wrist |
|
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Ipsilateral
|
On same side of body
The right arm and right leg are ipsilateral |
|
|
Contralateral (Peripheral)
|
On opposite sides of body
The right arm and left arm are contralateral |
|
|
Proximal
|
Nearer to point of attachment of limb to trunk
The elbow is proximal to the wrist |
|
|
Distal
|
Farther from point of attachment of limb to trunk
The wrist is distal to the elbow |
|
|
Superficial
|
Closer to surface of body
The skin is superficial to the muscles |
|
|
Deep
|
Farther from surface of body
The muscles are deep to the skin |
|
|
Cervical
|
neck
|
|
|
Thoracic
|
chest
|
|
|
Pectoral
|
breast
|
|
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Sternal
|
breast bone
|
|
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Abdominal
|
abdomen
|
|
|
Umbilical
|
navel
|
|
|
Coxal
|
hip
|
|
|
Pelvic
|
pelvis
|
|
|
Pubic
|
genital area
|
|
|
Dorsal
|
back
|
|
|
Scapular
|
shoulder blade region
|
|
|
Vertebral
|
spinal column
|
|
|
Lumbar
|
the area of the back between the lowest rib and buttocks
|
|
|
Acromial
|
highest point of the shoulder
|
|
|
Axillary
|
armpit
|
|
|
Brachial
|
arm
|
|
|
Cubital
|
elbow
|
|
|
Antecubital
|
Anterior surface of the elbow
|
|
|
Olecranal
|
posterior surface of the elbow
|
|
|
Antebracial
|
forearm
|
|
|
Carpal
|
wrist
|
|
|
Manual
|
hand
|
|
|
Palmer
|
palm of the hand
|
|
|
Digital
|
digits
|
|
|
Inguinal
|
grown where the thigh attaches to the pelvis
|
|
|
Gluteal
|
buttocks
|
|
|
Femoral
|
thigh
|
|
|
Patellar
|
anterior surface of the knee
|
|
|
Popliteal
|
posterior surface of the knee
|
|
|
Crural
|
anterior surface of the leg
|
|
|
Sural
|
posterior surface of the leg
|
|
|
Fibular
|
lateral side of the leg
|
|
|
Tarsal
|
ankle
|
|
|
Pedal
|
foot
|
|
|
Calcaneal
|
heel
|
|
|
Plantar
|
sole of foot
|
|
|
Parietal ....
|
Outer wall or lining
|
|
|
Visceral ....
|
Inner wall or lining
|
|
|
Pericardial Cavity
|
the cavity surrounding the heart
|
|
|
Pleural cavity
|
the cavity surrounding the lungs
|
|
|
Axial
|
Pertaining to the central part of the body, the head and trunk
|
|
|
Appendicular
|
Pertaining to the extremities or limbs
|
|
|
Cephalic
|
head
|
|
|
Facial
|
face
|
|
|
Frontal
|
forehead
|
|
|
Orbital
|
eye
|
|
|
Otic
|
ear
|
|
|
Buccal
|
cheek
|
|
|
Oral
|
mouth
|
|
|
Cranial
|
pertaining to the portion of the skull surrounding the brain
|
|
|
Occipital
|
the back of the head
|
|
|
Tuberosity
|
rough projection or elevation
Ex: tibia |
|
|
Crest
|
Ridgelike
Ex: hip bone |
|
|
Epicondyle
|
superior to condyle
Ex: femur |
|
|
Vertebral Column
|
26 bones
Vertebra Intervertebral Discs Cervical Thoracic Lumbar Sacrum Coccyx |
|
|
Thoracic Cage
|
Sternum
Ribs |
|
|
Sternum
|
3 bones
Manubrium - Jugular Notch - Sternal Angle (opposite 2nd rib) Body of Sternum Xiphoid (this is cartilage, ossifys completely by age 40) |
|
|
Ribs
|
12 pairs
True Ribs (7) - Costal Hyaline Cartilage connected False Ribs (5) - last 2 pairs are called floating Markings head - to demifacets on body neck Tubercle - to facet on transverse process Body |
|
|
Ribs
|
12 pairs
True Ribs (7) - Costal Hyaline Cartilage connected False Ribs (5) - last 2 pairs are called floating Markings head - to demifacets on body neck Tubercle - to facet on transverse process Body |
