Chapter 4: The Tissue Level of Organization

Question 1

stratified epithelium

Answer 1

several layers of cells

Question 2

epithelial tissue

Answer 2

covers the surfaces of the body, inside and out; produce glandular secretions

Question 3

functions of epithelial cells

Answer 3

• physical protection
• permeability
• sensation
• specialized secretions

Question 4

connective tissue

Answer 4

-support for the body
-connects all of its parts (mouth to anus)
-fill internal space
-store energy

Question 5

muscle tissue

Answer 5

contracts to produce movement

Question 6

neural tissue

Answer 6

conducts electrical impulses, carries information

Question 7

exocrine secretions

Answer 7

discharged onto the surface of the epithelium

Question 8

endocrine secretions

Answer 8

released into the surrounding tissue fluid and blood

Question 9

three types of cellular junctions

Answer 9

tight, gap, desmosomes

Question 10

tight junctions

Answer 10

-lipid layers of adjacent cell membranes are tightly bound together by interlocking membrane proteins
-prevent passage of water and solutes between cells

Question 11

gap junction

Answer 11

-two cells are held together by embedded membrane proteins
-allow passage of small molecules and ions between cells

Question 12

desmosome

Answer 12

locking of cells by intercellular cement and membrane proteins; more durable

those that resemble small discs are called “button desmosomes”; “hemidesmosomes” are half circles that attach cell to basement membrane

Question 13

basement membrane

Answer 13

network of protein fibers which lies between epithelium and underlying tissues

Question 14

simple epithelium

Answer 14

composed of a single layer of cells

Question 15

simple squamous epithelium

Answer 15

single layer of flattened cells

reduces friction, controls permeability/absorption/secretion

found in: ventral body cavities, lining of heart/blood vessels, alveoli

Question 16

simple cuboidal epithelium

Answer 16

single layer of cube shaped cells

limited protection, secretion/absorption

found in: glands/ducts, portions of kidney tubules

Question 17

simple columnar epithelium

Answer 17

single layer of tall cells that fit closely together

secretion/absorption

found in: lining of GI tract

Question 18

transitional epithelium

Answer 18

stretches readily

found in: ureters, urinary bladder, and part of the urethra

Question 19

pseudostratified columnar epithelium

Answer 19

single layer of irregularly shaped and sized cells that give the appearance of multiple layers

found in: ducts of certain glands and the upper respiratory tract, portions of the male reproductive tract

Question 20

stratified squamous epithelium

Answer 20

protects underlying tissues in areas subjected to high mechanical stress

found in: skin, lining of mouth, throat, rectum

Question 21

goblet cells

Answer 21

-unicellular glands
-secrete mucous which protect and line intestinal tract

Question 22

merocrine secretion

Answer 22

release of a substance from a gland via exocytosis; cell remains wholly intact

saliva from salivary glands, mucus in digestive and respiratory tracts, perspiration, milk

Question 23

apocrine secretion

Answer 23

release of a substance along with the apical portion of the cell; cell remains partially intact

milk in breasts, viscous underarm perspiration

Question 24

holocrine secretion

Answer 24

release of a substance caused by the complete rupture of a gland cell

skin oils and waxy coating of hair

Question 25

serous secretion

Answer 25

watery solution containing enzymes

Question 26

three basic components of connective tissue

Answer 26

cells, protein fibers, ground substance

Question 27

functions of connective tissue

Answer 27

*support and protection
*transportation of materials
*storage of energy reserves
*defense of the body

Question 28

connective tissue proper

Answer 28

tissue underlying skin, fatty tissue, tendons, ligaments

may be loose (adipose tissue) or dense (tendons and ligaments)

Question 29

fluid connective tissue

Answer 29

blood and lymph

Question 30

supporting connective tissues

Answer 30

cartilage and bone

Question 31

fibroblasts

Answer 31

responsible for producing and maintaining the connective tissue fibers and ground substance

Question 32

macrophages

Answer 32

engulf damaged cells or pathogens that enter tissue, release chemicals which mobilize the immune system

Question 33

fat cells

Answer 33

adipocytes

Question 34

mast cells

Answer 34

release heparin and histamine to begin body’s defense activities after an injury or infection

Question 35

collagen fibers

Answer 35

long, straight, and unbranched; strong and flexible

Question 36

elastic fibers

Answer 36

contain elastin; branched and wavy and return to original length after stretching

Question 37

reticular fibers

Answer 37

least common; thinner than collagen fibers, form a branching, interwoven framework in various organs

Question 38

ground substance

Answer 38

unstructured material that fills the space between the cells and contains fibers

Question 39

loose connective tissue

Answer 39

pads and supports surrounding tissue

Question 40

dense connective tissue

Answer 40

may be regular or irregular; mostly collagen fibers; tendons and ligaments

Question 41

Chondrocytes

Answer 41

cartilage cells

Question 42

hyaline cartilage

Answer 42

Most common type of cartilage; stiff but somewhat flexible

Where synovial fluid is present

ends of long bones, ribs, and nose

Question 43

elastic cartilage

Answer 43

cartilage with abundant elastic fibers; tolerates distortion without damage, returns to original shape

outer ear, epiglottis, and middle ear

Question 44

fibrocartilage

Answer 44

little ground substance, matrix is dominated by collagen fibers; resist compression and shock

vertebral column, pelvis, and around joints (medial/lateral epicondyles)

Question 45

Osteocytes

Answer 45

mature bone cells

Question 46

periosteum

Answer 46

fibrous (outer) and cellular (inner) layers covering bone

Question 47

mucous membranes

Answer 47

coated with secretions of mucous glands

line the digestive, respiratory, urinary and reproductive tracts

Question 48

serous membranes

Answer 48

line the ventral body cavities (peritoneal, pleural, pericardial)

Question 49

cutaneous membrane

Answer 49

skin

Question 50

synovial membranes

Answer 50

line joint cavities and produce fluid within the joint

Question 51

skeletal muscle

Answer 51

large, multiple nuclei, prominent striations, unbranched arrangement

Question 52

cardiac muscle

Answer 52

small, branch, single central nucleus, striated, interconnected by intercalated discs

Question 53

smooth muscle

Answer 53

small and spindle-shaped, central nucleus, no branches or striations

Respiratory, circulatory, digestive, reproductive tracts

Question 54

intercalated discs

Answer 54

specialized connections between myocardial cells containing gap junctions and desmosomes

Question 55

neuroglia

Answer 55

-physical support for neural tissue
-maintain the chemical composition of the tissue fluids
-supply nutrients to neurons
-defend the tissue from infection

Question 56

three parts of neuron

Answer 56

cell body, dendrites, axon

Question 57

dendrites

Answer 57

receive messages from other cells

Question 58

axon

Answer 58

send messages to other cells; end in synaptic terminals

Question 59

fibrosis

Answer 59

replacement of damaged cells with scar tissue

Question 60

characteristics of epithelial cells

Answer 60

*closely bound together
*free surface exposed to environment
*attachment to underlying basement membrane
*absence of blood vessels
*continually replaced/regenerated