mechanisms of development

Question 1

____________ is when the cell is reversibly designated as a specific type of cell

Answer 1

specification

Question 2

________________ is the commitment of a cell to a particular function in the future

Answer 2

determination

Question 3

T / F - prior to determination the cell can become any cell type

Answer 3

true

*after determination the cell is irreversibly committed to a specific lineage

Question 4

explain the multiple pathways by which determination may occur

Answer 4

1. the presence of specific mRNA and protein molecules
2. secretion of specific molecules by nearby cells

Question 5

___________ cause neighboring cells to follow a particular developmental pathway

Answer 5

morphogens

Question 6

____________ is the sturcture, function, and biochemical change of the cell to match the cell type

Answer 6

differentiation

Question 7

___________ are cells that have not yet differentiated or that give rise to other tcells that will differentiate

Answer 7

stem cells

Question 8

___________ is when a cell can differentiate into any cell type

Answer 8

totipotent

Question 9

____________ cells can differentiate into any cell type except those found in the placental structures

Answer 9

pluriopotent

Question 10

___________ cells can differentiate into multiple cells within a particular group

Answer 10

multipotent

*hemapoietic cells (blood cells) can differentiate into any cells found in the blood - wbc, rbc, platelets

Question 11

T / F - the determination and differentiation of a cell depends on the location of the cell as well as the identity of the surrounding cells

Answer 11

true

Question 12

give a definition for each of these words:

inducer
responder
competent

Answer 12

inducer = cell secreting signal
responer = responsive cell, cell being induced
compotent = able to respons to the inducing signal

Question 13

_______________ signals act on the same cell that secreted the signal in the first place

Answer 13

autocrine

Question 14

_____________ signals act on cells in the local are

Answer 14

paracrine

Question 15

_____________ signals do not usually incolce diffusion, but involve a cell directly stimulating receptors of an adjacent cell

Answer 15

juxtacrine

Question 16

___________ signals involve secreted hormones that travel through the bloodstream to a distant target tissue

Answer 16

endocrine

Question 17

inducers are often ___________ which are peptides that promote differentiation and mitosis in certain tissues

Answer 17

inducers

Question 18

what is one of the main methods of signaling?

Answer 18

signaling occurs via the use of gradients

*spectrum = locations closer to the origin of the morphogen will be exposed to higher concentrations that further away locations

Question 19

____________ is programmed cell death

Answer 19

apoptosis

Question 20

apoptosis process

cell –> __________ –> _________

Answer 20

cell –> apoptotic bleb –> apoptotic body

Question 21

what is the difference between apoptosis and necrosis?

Answer 21

apoptosis = programmed cell death

necrosis = cell death as a result of an injury