Lecture 15

Question 1

What does C14 content indicate?

Answer 1

how old tissue is

Question 2

What is apoptosis?

Answer 2

Programmed cell death
- not released into the extracellular milieu

Question 3

What is necrosis?

Answer 3

Bursting cells as a consequence of severe cell damage
- intracellular constituents are released into the extracellular milieu causing inflammation

Question 4

Function of Apoptosis

Answer 4

Safety system to remove cells that lost normal communication and control

Question 5

What are trophic factors?

Answer 5

Survival signals

Question 6

Why is apoptosis important in neuronal development?

Answer 6

matching the number of developing nerve cell to the number of target cells

Question 7

What is lost during apoptosis?

Answer 7

Asymmetrical lipid distribution

Question 8

What two things occur during apoptosis in lipid membrane?

Answer 8

• asymetry is not maintained and PS is exposed on the surface
• PS on cell surface signals to macrophages to phagocytose the cell

Question 9

What occurs during DNA fragmentation during apoptosis?

Answer 9

• apoptosis activates nucleases that cleave the DNA

Question 10

What is apoptosis executed by

Answer 10

capases

Question 11

Activation of initiator - caspase occurs by what

Answer 11

Aggregation of the procaspases with the help of adaptor proteins

Question 12

Aggregated initiator procaspase cleave each other which results in what

Answer 12

Formation of active caspase

Question 13

What initiates the apoptotic pathway?

Answer 13

Cytochrome C release from the mitochondria

Question 14

What causes p53 to activate apoptosis

Answer 14

prolonged DNA damage stress

Question 15

What is the pathway that activates apoptosis form outside of the cell?

Answer 15

extrinsic pathway

Question 16

What is the apoptosis pathway?

Answer 16

Regulator — Adapter — Effector

Question 17

What part of the mammalian instestine have a high turnover rate and therefore must constantly be replaced by new cells?

Answer 17

villi

Question 18

In mammalian intestine, new cells are produced where?

Answer 18

At the bottom of the crypt by a set of stem cells

Question 19

Cells born at the bottom of the epidermis differenetiate into what?

Answer 19

keratin containing skin cells, die and shed

Question 20

What is a tissue

Answer 20

are groups of cells that act together to perform a specific function

Question 21

What is the role of gap junctions

Answer 21

directly link the cytoplasm of neighboring cells (allow for exchange of ions and small molecules)

Question 22

Secreted proteins and polysaccharides form what?

Answer 22

strong network between the cells

Question 23

What links the cells to collagen of the ECM?

Answer 23

integrin

Question 24

Roles of epithelial tissues

Answer 24

Protection, secretion, absorption, excretion, filtration, diffusion, and sensory reception

Question 25

The end life of the cell

Answer 25

cells divide, differentiate and die