cell renewal

Question 1

what happens to the rate of proliferation as cells differentiate

Answer 1

the rate of proliferation decreases

Question 2

what do cells differentiate to produce

Answer 2

specialised cells

Question 3

cell turnover

Answer 3

Cell turnover refers to the process of cells being continuously replaced or replenished in a tissue

Question 4

is the proliferation of cells the same as cell differentiation

Answer 4

Cell proliferation refers to the process of cells dividing and increasing in number while cell differentiation involves the transformation of a less specialized or undifferentiated cell into a more specialized, mature cell with a specific function.

Question 5

most differentiated cells are able to proliferate, true or false

Answer 5

false

Question 6

cells arrest

Answer 6

refers to a situation in which the normal progression of a cell through the cell cycle is halted, leading to a temporary or permanent stop in cell division

Question 7

in what stage of the cell cycle do skin fibroblasts normally arrest

Answer 7

G0

Question 8

can endothelial cells proliferate

Answer 8

yes

Question 9

VEGF

Answer 9

Vascular Endothelial Growth Factor

Question 10

how do endothelial cells repair and regrow damaged cells

Answer 10

the release VEGF, which stimulates cell proliferation and outgrowth of new capillaries

Question 11

PDGF

Answer 11

Platelet-Derived Growth Factor

Question 12

how do skin fibroblasts repair and regrow their damaged and dead

Answer 12

by releasing PDGF from blood platelets, to stimulate the proliferation and migration of fibroblasts. this leads to the repair and regrowth of damaged skin tissues

Question 13

stem cells

Answer 13

unique type of cell with the remarkable ability to differentiate into a variety of cell types with specific functions

Question 14

hematopoietic stem cells

Answer 14

are a type of adult or somatic stem cell that gives rise to all the blood cell types in the body through a process called Hematopoiesis

Question 15

all blood cells derived from same population of HSCs in bone marrow, yes/no

Answer 15

yes

Question 16

the renewal of the intestinal epithelium is a continual process throughout life, true or false?

Answer 16

true, because the intestinal epithelial cells exposed to harsh environment, so their lifetime is only a few days before they die and shed into the digestive tract

Question 17

how are new intestinal cells formed in the intestinal tract

Answer 17

from continuous (but slow division) of SCs at bottom of intestinal crypts

SCs give rise to transit-amplifying cells, which divide rapidly

Transit-amplifying cells proliferate for 3 – 4 cell divisions

they then differentiate into 3 cell types of colon surface epithelium

Question 18

how many self renewing stem cells does each intestinal crypt approximately contain

Answer 18

6

Question 19

the three major cell lineages that the skin contains

Answer 19

hair follicles
epidermis
sebaceous gland

Question 20

function of the sebaceous gland

Answer 20

releases oils to lubricate the skin surface