Ch 4 Flashcards
Define Histology
the study of tissues
Define Tissue
a group of cells performing similar functions
Define Diffusion
movement of molecules from high concentration to low concentration
Define Filtration
the passing of a liquid through a filter. In the human body, the kidney functions as a filter. So, anatomically and physiologically, filtration is a process wherein waste and toxins are removed from the body through glomerulus filtration, which results in urine production
Define Absorption
the act of taking up or in by specific chemical or molecular action; especially the passage of liquids or other substances through a surface of the body into body fluids and tissues, as in the absorption of the end products of digestion into the villi that line the intestine.
Define Secretion
a process by which substances are produced and discharged from a cell, gland, or organ for a particular function in the organism or for excretion.
Define Excretion
the process of eliminating or expelling waste matter.
Define Regeneration
Regeneration is the natural process of replacing or restoring damaged or missing cells, tissues, organs, and even entire body parts to full function in plants and animals
Define Apical
an anatomical term of location for features located opposite the base of an organism or structure; on the outside part.
Define Basal
an anatomical term of location for features associated with the base of an organism or structure
Define Avascular
characterized by or associated with a lack of blood vessels
Define Innervated
to communicate nervous energy to; stimulate through nerves. to furnish with nerves; grow nerves into.
Define Cilia
a short microscopic hairlike vibrating structure found in large numbers on the surface of certain cells, either causing currents in the surrounding fluid, or, in some protozoans and other small organisms, providing propulsion.
Define Microvilli
are microscopic cellular membrane protrusions that increase the surface area for diffusion and minimize any increase in volume, and are involved in a wide variety of functions, including absorption, secretion, cellular adhesion, and mechanotransduction
Define Keratin
a fibrous protein forming the main structural constituent of hair, feathers, hoofs, claws, horns, etc
Define Extracellular
situated or taking place outside a cell or cells.
Define Matrix
the material (or tissue) in between a eukaryotic organism’s cells. The structure of connective tissues is an extracellular matrix. Finger nails and toenails grow from matrices
Define Tension
The pressure within a vessel, such as blood pressure: the pressure within the blood vessels. For example, elevated blood pressure is referred to as hypertension
Define CAMs
typically transmembrane (TM) glycoprotein receptors that help specific types of cells to undergo a selective process of cell-cell or cell-matrix interactions and act as a molecular link between the intra- and extra-cellular environment
Define Glycoprotein
any of a class of proteins that have carbohydrate groups attached to the polypeptide chain. Also called glycopeptide
Define Proteoglycans
a compound consisting of a protein bonded to glycosaminoglycan groups, present especially in connective tissue
Define Interstitial fluid
Fluid found in the spaces around cells. It comes from substances that leak out of blood capillaries (the smallest type of blood vessel)
Define Compression
the sensation of tissues being pressed or pushed together. This can happen because bone hits bone, squeezing whatever is in between
Define Soluble
susceptible of being dissolved in or as if in a liquid and especially water; the opposite of a solvent
Name the four basic tissue types in the body and state their general function
Epithelial: (Covers) forms boundaries between different environments, protects, secretes, absorbs, and filters
connective: (supports) Supports, protects, and binds other tissues together
muscle: (Moves) contracts to cause movements
nervous tissue: (Controls) Internal communication
State the 3 primary germ layers. From lecture know the origin of the 4 basic tissues
the three primordial germ layers: ectoderm, mesoderm and endoderm
Define Mesenchyme
a loosely organized, mainly mesodermal embryonic tissue which develops into connective and skeletal tissues, including blood and lymph
Know the 2 classes of epithelial tissues and state their functions
covering and lining epithelium tissue: forms the outer layer of the skin; dips into and lines the open cavities of the urogential, digestive, and respiratory systems; and covers the walls and organs of the closed ventral body cavity
glandular epithelium tissue: fashions the glands of the skin
Know the 6 basic functions of epithelia that cover and line
protection absorption filtration excretion secretion sensory reception
Know the 6 distinguishing characteristics of epithelial tissues
cellularity specialized contacts polarity support by connective tissue avascular but innervated regeneration
Know the criteria to classify epithelial tissues based on arrangement and cell shape
Layout: how the cells are laid out
simple: a single layer of connected cells, with each cell attached to the basement membrane
stratified: 2 or more layers of cells stacked on top of each other. The cells on the basal surface are attached to the basement membrane; those on the apical surface border
an open space
Shape: the shape the cells take
Squamous: flat cells with flat, disc-shaped nuclei.
Cuboidal: cube-shaped cells with spherical, centrally located nuclei
Columnar: taller than they are wide, like columns. The nuclei of columnar cells are located near the
basal surface and are commonly oval in shape, elongated from top to bottom
Describe the unique characteristics of the following epithelial tissues. Know their function based on tissue structure.
a. Simple squamous:
b. Endothelium:
c. Mesothelium:
d. Simple cuboidal:
e. Simple columnar:
f. Pseudostratified columnar:
g. Stratified squamous-
keratinized:
nonkeratinized:
h. Stratified cuboidal:
I. Stratified columnar:
j. Transitional:- a single layer of flat cells / Allows materials to pass by diffusion and filtration in sites where protection is not important; secretes lubricating substances in serosae
- the lining of lymphatic vessels, blood vessels, and heart
- the epithelium of serous membranes in the ventral body cavity
- a single layer of cubed cells / Forms walls of smallest ducts of glands and many kidney tubules / secretion and absorption
- a single layer of tall cells, aligned like soldiers in a row / Absorption; secretion of mucus, enzymes, and other substances; ciliated type propels mucus (or reproductive cells) by ciliary action.
- Single layer of columnar epithelial cells but layered appearance of nuclei suggest multiple layers of cells / Secrete substances, particularly mucus; propulsion of mucus by ciliary action.
- multiple layers of flat cells / Protects underlying tissues in areas subjected to abrasion
- single layers of cube shaped cells / found in sweat and mammary glands
- multiple layers of cells that are taller than wide / Small amounts in pharynx, male urethra, and lining some glandular ducts / Also occurs at transition areas between two other types of epithelia / only apical layer columnar
- Resembles both stratified squamous and stratified cuboidal; basal cells cuboidal or columnar; surface cells dome shaped or squamous-like, depending on degree of organ stretch / Stretches readily, permits stored urine to distend urinary organ.
Describe the structure and function of endocrine glands
Ductless / secrete products directly into the interstitial fluid or the bloodstream
Describe the structure and function of exocrine glands
possess ducts / Secrete products into ducts / Examples include mucous, sweat, oil, and salivary glands
Identify a unicellular exocrine gland. State the location and function
has extra room in its cells that hold/produce secretory vesicles containing mucus / Found in epithelial linings of intestinal and respiratory tracts / they produce mucin, which when mixed with water creates mucus, a slimy lubricating protective coating
Identify the 2 structures of glandular ducts
duct
secretory unit
Identify the structure of glandular secretory units
Simple glands (unbranched duct) or compound glands (branched duct) Cells: tubular, alveolar, or tubuloalveolal
Distinguish between Merocrine and Holocrine secretion. Give examples of each
Merocrine – most prevalent – secrete products by exocytosis as produced / ex. sweat
Holocrine – accumulate products within then rupture / ex. sebaceous glands (Sebum lubricates the skin to protect against friction and makes it more impervious to moisture)
State the basic functions of connective tissues
Function is to “connect” one structure to another structure
CT is the “glue” and “filler” of the body
Describe the common characteristics of connective tissue
-relatively few cells, lots of extracellular matrix
extracellular matrix composed of ground substance and fibers
-Varying degrees of vascularity( blood vessels)
-embryonic origin (originate from the embryonic tissue mesenchyme)
Identify the components of the extracellular matrix and state the functions
Collagen fiber: Long, unbranching, strong, flexible & resistant to stretching / High tensile strength / 25% of all protein in human body
Elastic fiber: Networks of long, thin, elastin fibers that stretch and recoil / Allow blood vessels to stretch and relax
Reticular fiber: Short, fine, highly branched collagenous fibers (different chemical makeup and form than collagen fibers) / Branch, forming networks that offer more “give” / Found in organs with abundant spaces such as the liver, spleen, and lymph nodes.
Ground substance: is a gel like substance made of large sugar and sugar-protein molecules / The fluid-filled ground substance functions to cushion and protect body structures (connective tissue proper), to withstand compressive stresses (cartilage), or to hold the tissue fluid that bathes all the cells in our body (areolar connective tissue). In bone tissue, the secreted ground substance is embedded with calcified mineral salts, which make the matrix hard and contribute to its function in supporting the body.
. Identify the immature cells and the class of connective tissue to which they belong
Blast cells -
Fibroblasts in connective tissue proper
Chondroblasts in cartilage
Osteoblasts in bone
Hematopoietic stem cells in bone marrow
Know how the mature cells are different and state their functions
Cyte cells -
Mature form; maintain matrix
Chondrocytes in cartilage
Osteocytes in bone
Describe the structural characteristics of the following loose connective tissues. Include the cell types, locations and functions.
a. Areolar
b. Adipose
c. Reticular
- This tissue underlies almost all the epithelia of the body and surrounds almost all the small nerves and blood vessels, including the capillaries. The structure of this tissue reflects its basic functions: Supporting and binding other tissues / Holding body fluids / Defending the body against infection / Storing nutrients as fat
- similar to areolar connective tissue in structure and function, but its nutrient-storing function is much greater. Correspondingly, adipose tissue is crowded with fat cells, which account for 90% of its mass. These fat cells are grouped into large clusters called lobules. occurs in the layer beneath the skin called the hypodermis and in the serous membrane on the stomach and intestines called mesenteries.
-Reticular connective tissue resembles areolar tissue, but the only fibers in its matrix are reticular fibers / The bone marrow, spleen,
and lymph nodes, which house many free blood cells outside their capillaries, consist largely of reticular connective tissue
Describe the structural characteristics of the following dense connective tissues. Include the cell types, locations and functions.
a. Dense Regular
b. Dense Irregular
f. Elastic
- similar to areolar tissue, but its collagen fibers are much thicker / This tissue dominates the leathery dermis of the skin, which is commonly stretched, pulled, and hit from various angles. This tissue also makes up the fibrous capsules that surround certain organs in the body, such as kidneys, lymph nodes, and bones / Attaches muscles to bones or to muscles; attaches bones to bones; withstands great tensile stress when pulling force is applied in one direction.
- Allows recoil of tissue following stretching; maintains pulsatile flow of blood through arteries; aids passive recoil of lungs following inspiration / Walls of large arteries; within certain ligaments associated with the vertebral column; within the walls of the bronchial tubes / closely packed thick bundles of collagen fibers irregularly arranged
- made of elastic fibers / many of larger arteries have in walls / very resilient and will stretch / vocal cords
Describe the general characteristics of cartilage, the matrix and cells. State the general function
matrix: matrix contains thin collagen fibrils, a ground substance, and an exceptional quantity of tissue fluid; in fact, cartilage consists of up to 80% water / The arrangement of water in its matrix enables cartilage to spring back from compression
cell: chondrocyte / Each chondrocyte resides within a cavity in the matrix called a lacuna. Immature chondrocytes are chondroblasts, cells that actively secrete the matrix during cartilage growth
Know the specific differences between the following cartilages. Include the matrix and cell types, locations and functions.
a. Hyaline cartilage
b. Elastic cartilage
c. Fibrocartilage
- Amorphous but firm matrix; collagen fibers form an imperceptible network; chondroblasts produce the matrix and, when mature (chondrocytes), lie in lacunae / Supports and reinforces; serves as resilient cushion; resists compressive stress / Forms the fetal skeleton, present at ends of bones that articulate with each other and in trachea, larynx and nose
- Similar to hyaline cartilage, but more elastic fibers in matrix / Maintains the shape of a structure while allowing great flexibility / epiglottis & external ear
-Matrix similar to but less firm than that in hyaline cartilage; thick collagen fibers predominate / Tensile strength with the ability to
absorb compressive shock / Intervertebral discs; pubic symphysis; discs of knee joint.
Describe basic structure of bone connective tissue to include matrix, cells and functions
Hard, calcified matrix containing many collagen fibers; osteocytes lie in lacunae. Very well vascularized / Supports and protects
(by enclosing); provides levers for the muscles to act on; stores calcium and other minerals and fat; marrow inside bones is the site for blood cell formation (hematopoiesis). / also called osseous tissue
Describe the basic structure of blood connective tissue to include matrix, cells functions
Red and white blood cells in a fluid matrix (plasma). / Transport respiratory gases, nutrients, wastes, and other substances
Describe the general characteristics of nervous tissue to include cell types, locations and functions
Neurons – nerve cells that are capable of initiating and conducting electrical activity throughout the body
Neuroglia (Glial) – cells that support the neurons
Function of nerve cells is communication and control of body functions
Brain, spinal cord, and nerves.
State the general characteristics of muscle tissue to include the proteins that carry out contraction
Comprised of cells called fibers
When stimulated by the nervous system, fibers contract
The result of contraction is movement i.e. movement of bones, blood, food, sperm
highly vascularized
Describe the specific differences between the 3 types of muscle tissue. Include the cell descriptions, locations and functions.
a. Skeletal
b. Cardiac
c. Smooth Muscle
- Long, cylindrical, multinucleate cells; obvious striations / Voluntary movement; locomotion; manipulation of the environment; facial expression / In skeletal muscles attached to bones or occasionally to skin
- Branching, striated, generally uninucleate cells that interdigitate at specialized junctions / As it contracts, it propels blood into the circulation; involuntary control / The walls of the heart
-Spindle-shaped cells with central nuclei; no striations; cells arranged closely to form sheets / Propels substances or objects
(foodstuffs, urine, a baby) along internal passageways; involuntary control / Mostly in the walls of hollow organs
Describe the basic structural differences between the 3 types of membranes. Include the types of tissues, cells, locations and functions.
a. Cutaneous
b. Mucous
c. Serous
- Skin / Keratinized stratified squamous epithelium (epidermis) attached to a thick layer of connective tissue (dermis) / Dry membrane
- All called mucosae / Line body cavities open to the exterior (e.g., Digestive, respiratory, urogenital tracts) / Moist membranes bathed by secretions (or urine) / Epithelial sheet lies over layer of connective tissue called lamina propria / May secrete mucus
- found in closed ventral body cavity / Simple squamous epithelium (mesothelium) resting on thin areolar connective tissue / Parietal serosae line internal body cavity walls / Visceral serosae cover internal organs / Serous fluid between layers / Moist membranes / Pleurae, pericardium, peritoneum
Define Inflammatory response and state its purpose
occurs when tissues are injured by bacteria, trauma, toxins, heat, or any other cause
to eliminate the initial cause of cell injury, clear out necrotic cells and tissues damaged from the original insult and the inflammatory process, and initiate tissue repair
Identify the four cardinal signs of inflammation
heat
pain
redness
swelling
Identify the 3 steps required to restore an injured tissue to normal structure and function. Include granulation tissue.
a.
b.
c.
1) Inflammation sets stage
Release of inflammatory chemicals
Dilation of blood vessels
Increase in vessel permeability
Clotting occurs
2)Organization restores blood supply
The blood clot is replaced with granulation tissue
Epithelium begins to regenerate
Fibroblasts produce collagen fibers to bridge the gap
Debris is phagocytized
3)Regeneration and fibrosis
The scab detaches
Fibrous tissue matures; epithelium thickens and begins to resemble adjacent tissue
Results in a fully regenerated epithelium with underlying scar tissue
Define fibrosis. How would it interfere with organ functions
the thickening and scarring of connective tissue, usually as a result of injury
Fibrosis is the excessive accumulation of extracellular matrix (ECM) that can lead to distortion of tissue architecture and loss of organ function
