Unit 4: Tissue level of Organization

Question 1

define histology

Answer 1

the study of tissue

Question 2

define tissue

Answer 2

a group of cells working together to perform a function

Question 3

define extracellular matrix (ECM)

Answer 3

non living part that are materials located between cells. Cells secreted it into the tissue and can be proteins, minerals, carbs, glycoproteins, water and gases.

Question 4

define cell junction

Answer 4

points where membrane of adjacent cells meet

Question 5

define polarity

Answer 5

superior and inferior regions of cells are different with respect to structure and function

Question 6

define apical surface

Answer 6

superior region, the “exposed” surface. Can be exposed to outside of the body or to the hollow cavity of an organ. It faces away from the basement membrane. Can have cilia or microvilli

Question 7

define basal surface

Answer 7

Inferior region; its “attached” surface. attached to basement membrane by hemidesmosome junction

Question 8

define basement membrane

Answer 8

ECM layer between epithelial tissue and connective tissue. Duties include anchors, supports, and regulates exchange of material

Question 9

define avascular

Answer 9

does not have blood supply, but obtains nutrient from connective tissue below it

Question 10

define innervation(innervated)

Answer 10

Has a nerve supply

Question 11

define squamous

Answer 11

a flat, scale like cell

Question 12

define secretion (with respect to a gland)

Answer 12

send solutes out of cell

Question 13

define cuboidal

Answer 13

a box like cells with a. round nucleus that tends to be in the center

Question 14

define columnar

Answer 14

Tall rectangular cell that has a long, oval nucleus that usually hands by the basal surfce

Question 15

define simple

Answer 15

sing layer of cell

Question 16

define stratified

Answer 16

more than one layer of cell

Question 17

define endothelium

Answer 17

inner lining of vessels and heart that reduce friction

Question 18

define mesothelium

Answer 18

lining of ventral body cavity

Question 19

define goblet cells

Answer 19

mucus secreting cells

Question 20

define keratin (keratinized

Answer 20

Having keratin, a tough protein that provides strength, in apical layer. Dry apical layer because the protein dehydrates the tissue.

Question 21

define gland

Answer 21

a structure that makes or secrets a product

Question 22

define mesenchyme

Answer 22

embryonic tissue

Question 23

define ground substance

Answer 23

a fluid, gel like, or almost solid substance made of nutrients, glycoproteins(bind cells to ground substance) and large polymers called GAGS (which regulate water balance)

Question 24

define hyaluronic acid

Answer 24

a type of glycosaminoglycans (GAGs)

Question 25

define chondroitin sulfate

Answer 25

Another type of glycosaminoglycans (GAGs)

Question 26

define muscle fibers

Answer 26

Long fibrous cells

Question 27

define intercalated disc

Answer 27

Thick areas of cell membrane that have gap junctions between adjacent cells

Question 28

Compare and contract the structure and function of 3 types of cells junctions: tight junction, desmosomes (and hemidesmosomes,) and gap junctions: list where each type occurs in the body

Answer 28

Tight junction: no space between cells to prevent leakage and located where leaks are to be prevented like lining of digestive organs

Question 29

Describe the 2 parts of a tissue: cells and extracellular matrix

Answer 29

Cells are the living parts. ECM is the non living part that is between the cells. Cells secret materials in the ECM.

Question 30

Compare and contract the structure and function of 3 types of cells junctions: tight junction, desmosomes (and hemidesmosomes,) and gap junctions: list where each type occurs in the body

Answer 30

Tight junction: no space between cells to prevent leakage and located where leaks are to be prevented like lining of digestive organs
Desmosomes: ticken area of membranes (called plaque) that holds cell together. plate attaches to microfilaments or intermediate filaments. They prevent separation of cells and holds cells tougher as a sheet. Found in epidermis and cardiac muscles
Hemi desomomes” happy desmosome and is used to attach cell to basement membrane
Gap junction : channels that hold cell together that is used for chemical communication. found in muscles cells and nerve cells

Question 31

What is the 6 functions of epithelial tissue

Answer 31

1. separates tissues/structure and forms boundaries between them
2. absorption and secretion
3. filtration
4. decking stimuli
5. projection
6. reduces friction

Question 32

list 4 locations of epithelial tissue

Answer 32

1. external body covering (skin)
2. Covering outside of organ
3. lining the inside of hollow orange
4. glands

Question 33

describe in detail the 6 characteristics of epithelial tissue

Answer 33

1. cells are tightly packed with little ECM
2. Cells junction hold cells together as sheets
3. CT is always bellow the eptitheal tissue for support, nourishiment, and strength
4. has polarity with apical to the exposed surface and basal to the attached surface
5. avascular (no blood supply) and innervated (has nerve supply)
6. fast regeneration rate

Question 34

How are epithelial tissue named?

Answer 34

by number of tissue layer : simple (one) stratified (more than one) pseudo stratified (one layer but looks like more) and by shape squamous (flat, scale like) cuboidal (boxy like cell with rounded centered nucleus) and columnar (tall rectangular cell with long oval nucleus at basal surface

Question 35

What is the function, location, and struck characteristically of simple squamous

Answer 35

one layer of squamous shaped cells that are thin and fragile. It allows materials to pass through, reduces friction and secretes serous fluids. Found innings, inner lining of vessels and heart, lining of ventral body cavity , and kidney tubules

Question 36

what is the function location and structural characteristics of simple cuboidal

Answer 36

one layer of cuboidal cells that are rounded and can have cilia or microvilli. It is used for secretions, absorption, and to move extracellular substances across the membrane. Found ion kidney tubules, thyroid gland, bronchioles inland, and ducts of glands like salivary.