Ch. 4- Tissues Part 1

Question 1

What are tissues?

Answer 1

Collections of cells and cell products that perform specific, limited functions

From same region of embryo

Question 2

What is histology?

Answer 2

study of tissues

Question 3

What is cytology?

Answer 3

study of cells

Question 4

What is a longitudinal section?

Answer 4

tissue cut along the longest direction of an organ

Question 5

What is a cross section?

Answer 5

tissue cut perpendicular to length of an organ

Question 6

What is a oblique section?

Answer 6

tissue cut at an angle b/n cross and longitudinal section

Question 7

Are CT cells widely separated by matrix?

Answer 7

yes

Question 8

Are epithelial and muscle cells widely separated by matrix?

Answer 8

No

Question 9

What makes up the matrix?

Answer 9

Fibrous protein (elastin, collagen)

Ground Substance

Question 10

What is ground substance?

Answer 10

supports, binds, stores water and provides a medium for exchange of substances b/n cells and blood

Contains:

• water
• various large molecules

may be fluid, semi fluid, gelatinous, calcified

Question 11

What are the 4 types of tissue?

Answer 11

1) Epithelial
2) CT
3) Muscle
4) Neural

Question 12

What is the 4 functions of epithelial tissue?

Answer 12

1) physical protection
2) control permeability
3) provide sensation
4) produce specialized secretions

Question 13

What does CT do?

Answer 13

fills internal spaces

provides structural support for other tissues

transports materials w/n the body

stores energy

Question 14

What does muscle tissue do?

Answer 14

specialized for contraction

Question 15

What does neural tissue do?

Answer 15

carries info from one part of the body to another via electrical impulses

Question 16

What are the 2 types of epithelial tissue?

Answer 16

1) covering and lining epithelia

2) glandular epithelia

Question 17

What is covering/ lining epithelia?

Answer 17

external body surfaces

lines internal surfaces of body cavities, hollow organs, ducts and passageways

Question 18

What is glandular epithelia?

Answer 18

secretory tissue in glands

Question 19

What is the apical surface?

Answer 19

upper, free surface that faces the exterior of the body and internal space of body cavity, cavity of internal organ, and passageway or duct

may bear microvilli and cilia

Question 20

What is the basal surface?

Answer 20

lower, attached surface

attached to the noncellular basal lamina which consists of proteins

Question 21

What is cellularity?

Answer 21

epithelia are composed of closely packed cells

Question 22

What is attachment?

Answer 22

the basal surface of the deepest layer of epithelial cells attach to underlying basement membrane

Question 23

What is avascularity?

Answer 23

obtain nutrients from blood vessels in adjacent CT by diffusion and absorption

Question 24

What is regeneration?

Answer 24

cells are continuously replaced through the division of stem cells in the epithelia

Question 25

What are the 2 layers the basement membrane consist of?

Answer 25

1) basal lamina | 2) reticular lamina

Question 26

What is the basal lamina?

Answer 26

layer of ECM secreted by the epithelial cells on which epithelium sits

Question 27

What is the reticular lamina?

Answer 27

thin layer of extracellular layer composed chiefly of collagen fibers produced by fibroblasts serves to anchor the basal lamina to underlying CT

Question 28

Do epithelia have microvilli and cilia?

Answer 28

yes

Question 29

What are cell junctions?

Answer 29

specialized areas of the plasma membrane that attach a cell to another cell and extracellular materials

Question 30

What are 3 common types of cell junctions?

Answer 30

1) gap junctions or communicating junctions 2) tight (occluding) junctions 3) desmosomes

Question 31

What are Cell adnhesion molecules (CAMs)?

Answer 31

transmembrane proteins that connect the plasma membrane of adjacent epithelial cells

Question 32

What are connexins in gap junctions?

Answer 32

gap junction proteins in adjacent cell membranes interlock to form connexons b/n the 2 cells

Question 33

What are connexons in gap junctions?

Answer 33

hollow cylinders form when connexins in adjacent cell membrane interlock form narrow passageways b/n adjacent cells

Question 34

What do gap junctions do?

Answer 34

allow rapid communication allow small solutes to pass b/n cells coordinate contractions in heart muscle

Question 35

What are tight (occluding) junctions?

Answer 35

consists of interlocking membrane proteins b/n adjacent plasma membranes prevent substances and bacteria from passing b/n cells found in GI and urinary tract inferior to tight junctions, a continuous adhesion belt forms

Question 36

What are adhesion belts?

Answer 36

zonula adherens or adherens junction inferior to the tight junctions consists of plaque, a dense layer of proteins, that attach to and encircles the cytoplasmic side of membrane

Question 37

What are transmembrane proteins of the adhesion belt?

Answer 37

adjacent cells are anchored in the dense area w/n each cell these proteins extend into the intercellular space b/n adjacent cells attach to each other

Question 38

What are the terminal web of the adhesion belt?

Answer 38

located on the cytoplasmic side of the plasma membrane consists of a horizontal network of microfilaments and intermediate filaments serves as attachment site for the bundles of actin filaments of microvilli

Question 39

What are desmosome?

Answer 39

transmembrane proteins link the plasma membrane to either an adjacent plasma membrane or basement membrane

Question 40

What are spot desmosomes?

Answer 40

transmembrane proteins of adjacent cells are anchored in a dense area w/n each cell extend into the intercellular space b/n the adjacent cells and attach to each other dense area is connected to the cytoskeleon

Question 41

What are hemidesmosomes?

Answer 41

transmembrane proteins of adjacent cells are anchored in a dense area w/n each cell helps anchor the ceel to underlying tissue

Question 42

What are the 2 functions of desmosomes?

Answer 42

1) help to resist stretching and twisting tissue | 2) help prevent tearing and separation of tissue