Tissue Level

Question 1

What are body tissues?

Answer 1

cells with similar function and/or structure can be grouped together to form tissues

Question 2

Four types of tissues?

Answer 2

• muscle
• nervous
• connective
• epithelial

Question 3

What does epithelial tissue form?

Answer 3

1) covering on body surfaces (skin)- line urinary, reproductive, digestive, respiratory tract
2) lining of body cavities (serous and mucous membranes)
3) glandular tissue of the body (endocrine glands)

Question 4

How are epithelial tissues classified?

Answer 4

• number of cell layers
• cell shape

Question 5

What are epithelial tissue functions?

Answer 5

• protection
• absorption
• excretion
• filtration
• secretion
• sensation

Question 6

Protection (epithelial)

Answer 6

from abrasion, injury, dehydration, chemical and biological agents

Question 7

Absorption (epithelial)

Answer 7

take in food and nutrients from the environment

Question 8

Filtration (epithelial)

Answer 8

differ in degree of ions, proteins, hormones that can cross through

Question 9

Excretion (epithelial)

Answer 9

remove waste products from the body- through the epithelial lining/glands

Question 10

Secretion (epithelial)

Answer 10

produces and releases secretions from the body- mucus, enzymes, hormones for body protection and regulation

Question 11

Sensation (epithelial)

Answer 11

most have large sensory nerve supply to sense pain or other stimuli

Question 12

What can the cells in neuroepithelia sense?

Answer 12

sight, sense, touch, hearing, equilibrium

Question 13

Epithelial tissue characteristics?

Answer 13

• polarity
• attachment
• cellularity
• avascular but innervated
• regeneration

Question 14

Polarity (epithelial)

Answer 14

2 sides- apical (top) and basal (bottom)

Question 15

How are organelles arranged in epithelial tissues?

Answer 15

spread out unevenly

Question 16

Cellularity (epithelial)

Answer 16

tightly packed celled joined by junctions- not much space between them

Question 17

Attachment (epithelial)

Answer 17

bottom is attached to basal lamina, holding cell in place and protecting abrasion

Question 18

Basal Lamina

Answer 18

thin layer made of collagen and other materials

Question 19

Avascular but innervated (epithelial)

Answer 19

has no blood vessels (nutrients through diffusion/absorption) but has nerves for sensation

Question 20

Rengeneration (epithelial)

Answer 20

heals fast- old/ damaged cells are quickly replaced by stem cells

Question 21

Epithelial tissue components

Answer 21

• Epithelia
• Glands

Question 22

Epithelia

Answer 22

cover exposed surfaces, lines internal passageways and cavities, contains secretory cells/gland cells

Question 23

Glands

Answer 23

derived from epithelia, mostly secretory cells

Question 24

Exocrine Glands

Answer 24

secrete onto external surfaces or internal ducts that lead to the exterior

Question 25

Endocrine Glands

Answer 25

secrete hormones or precursors into interstitial fluid through blood

Question 26

Epithelial tissue specializations

Answer 26

- polarity - microvilli - cilia

Question 27

Apical surface

Answer 27

top; free surface, faces space (lumen)

Question 28

Basolateral surface

Answer 28

bottom; attaches to other cells and membrane

Question 29

Microvilli (epithelial)

Answer 29

- in digestive system and kidneys - increase surface area 20x for absorption

Question 30

Cilia (epithelial)

Answer 30

- ~250 cilia in each cell - clear mucus and trapped dust by beating - on ciliated epithelium (respiratory)

Question 31

Damage to cilia

Answer 31

- smoking, nicotine, toxins stop beating, allowing mucus build-up - risk of infection and disease