A&P I Exam I

negative feedback

effectors negate stimulus

example of negative feedback

body temperature regulation

effectors

cause responses that alter conditions in the internal environment

positive feedback

effectors reinforce stimulus

example of positive feedback

childbirth, blood clotting

tissues

collections of cells and cell products that perform specific functions

four tissue types

epithelial, connective, muscle, neural

epithelia

layers of cells that cover internal or external surfaces

glands

attached to or derived from epithelia that produce secretions

functions of epithelia

protection, permeability, sensation, secretions

tight junction

a firm seal between two adjacent animal cells created by protein adherence

image of tight junction

desmosomes

Anchoring junctions that prevent cells from being pulled apart

image of desmosomes

gap junctions

provide cytoplasmic channels between adjacent animal cells

image of gap junction

tight junctions are found

in the cells of epithelial tissue that lines the stomach, intestines, and urinary bladder

gap junctions are found

cardiac muscle cells

hemidesmosome

anchors intermediate filaments in a cell to the basal lamina

simple squamous epithelia

absorption and diffusion, heart/blood vessels

simple cuboidal epithelia

Secretion and absorption

Glands and portions of kidney tubules

simple columnar epithelium

absorption; secretion, intestines and stomach

stratified squamous

protection, epidermis, mouth vagina

transitional epithelium

urinary bladder, stretches and recoils

psuedostratified columnar epithelium

secretions, respiratory trach, cilia, male reproductive tract

endocrine glands are

ductless

endocrine glands release hormones into

interstitial fluid/bloodstream

example of endocrine gland

thyroid, pituitary, pancreas, gonads

exocrine glands

have ducts

merocrine secretion

release of a substance from a gland via exocytosis

example of merocrine secretion

sweat/saliva

apocrine secretion

release of a substance along with the apical portion of the cell

example of apocrine secretion

mammary glands

holocrine secretion

release of a substance caused by the rupture of a gland cell (replaced with stem cell), which becomes part of the secretion

example of holocrine secretion

sebaceous glands of hair follicles

goblet cells

excrete mucus

goblet cells can be found

trachea, intestinal lining

simple ducts have

no branching

example of single duct

interstitial, sebaceous gland

compound glands

multiple branches

types of loose connective tissue

areolar, adipose, reticular

all connective tissue has

protein fibers, fluid ground substance

function of loose connective tissue

binds organs together, holds tissue fluids

the connective tissue matrix is made of

extracellular fibers and ground substance

functions of connective tissue

binding and support, protection, insulation, transportation, immunity

function of fluid connective tissue

transportation

fibroblasts

always present and secrete protein/fibers

fibroblasts image

macrophages

phagocytize foreign substances and help activate T cells

image of fixed macrophage

image of free macrophage

adipocytes contain

single large fat droplet

image of adipocyte

mesenchymal cells

stem cells that respond to injury or infection

image of mesenchymal cell

melanocytes

synthesize and store melanin

image of melanocytes

mast cells

stimulate inflammation

mast cells secrete

histamine and heparin

image of mast cell

lymphocyte

immune cells that migrate

image of lymphocyte

collagen fibers are

long, straight and unbranched

collagen fibers resist force

in one direction

image of collagen fiber

reticular fibers are

thinner and branched

reticular fibers resist

many directions

image of reticular fibers

elastic fibers

wavy, branched

image of elastic fibers

ground substance is made of

water, proteins, glycoproteins, proteoglycans

function of ground substance

Diffusion of nutrients and wastes, lubricant, barrier

image of ground substance

dense connective tissue

few blood vessels, heals slowly

dense regular connective tissue is

tightly packed with parallel collagen fibers

example of dense regular connective tissue

tendons and ligaments

tendons

muscle to bone

ligament

bone to bone/stabilize organs

dense irregular connective tissue

resists force in many directions, networks of collagen fibers

example of dense irregular connective tissue

around cartilages and bones, deep dermis, joint capsules, around organs

cartilage

gel type ground substance for shock absorption and protection

bone is calcified by

calcium salts, minerals

cartilage matrix contains

polysaccharides and proteoglycans

chondrocytes

cartilage cells

chondrocytes are surrounded by

lacunae (chambers)

cartilage is (vascular/avascular)

avascular

chondrocytes produce

anti-angiogenesis factor (vessel formation)

perichodrium

surrounds cartilage

outer perichondrium

fibrous, DICT, strength/mechanical support

inner perichondrium

cellular growth and maintenance

hyaline cartilage function

reduces friction, stiff/flexible support

most common cartilage

hyaline (few fine fibers)

hyaline cartilage is found in

synovial joints, rib tips, sternum, bronchi...

elastic cartilage is found in

external ear and epiglottis

elastic cartilage

supportive but bends easily

fibrocartilage

very tough, limits movement

fibrocartilage is found in

knee joints, pubic bones, intervertebral joints

fibrocartilage contains

dense collagen fibers

epidermis is (avascular/vascular)

avascular

epidermis epithelium

stratified squamous