Biology Prelim 3 Review

Question 1

4 fundamental mechanisms that drive development

Answer 1

cell proliferation, cell specification (differentiation), cell rearrangements, cell signaling

Question 2

3 ways to make organism larger

Answer 2

cell proliferation, cell enlargement, cell accretion

Question 3

cell specification depends on…

Answer 3

regulation of gene expression

Question 4

morphogenesis

Answer 4

the acquisition of embryonic shape

Question 5

cell rearrangements depends on…

Answer 5

changes in the cytoskeleton

Question 6

3 methods experimental embryologists used to study development of embryos

Answer 6

labeling, cutting, and transplantation

Question 7

only organism with complete fate map

Answer 7

C. elegans

Question 8

induction

Answer 8

ability of some embryonic cells to influence the fate of neighboring cells

Question 9

how is induction accomplished

Answer 9

through cell signaling

Question 10

epigenesis

Answer 10

acquisition of fate is progressive during development

Question 11

what are the two mechanisms that controls the expression of the transcription factor at the beginning of the cascade

Answer 11

asymmetric distribution of cytoplasmic determinants and cell signaling

Question 12

organizer

Answer 12

group of cells or region of embryo which produces signals which can influence/induce other cells to become specified

Question 13

tight junction

Answer 13

seals neighboring cells together in an epithelial sheet to prevent leakage of molecules between them

Question 14

adherens junction

Answer 14

joins an actin bundle in one cell to a similar bundle in a neighboring cell

Question 15

desmosome

Answer 15

joins the intermediate filaments in one cell to those in a neighbor

Question 16

gap junctions

Answer 16

form channels that allow small water soluble molecules to pass from cell to cell

Question 17

hemidesmosome

Answer 17

anchors intermediate filaments in a cell to basal lamina

Question 18

gene

Answer 18

DNA + promoter + regulatory sequences

Question 19

gene expression

Answer 19

transcription + translation

Question 20

expression pattern

Answer 20

spatial localization of genes within an embryo or organism where a gene is transcribed

Question 21

morula

Answer 21

an embryo containing a few hundred cells that are morphologically equivalent to one another

Question 22

RNA polymerase II

Answer 22

responsible for transcribing protein encoding genes; recognizes sequence at promoter and synthesizes mRNA sequence until it reaches a stop codon

Question 23

what precedes the appearance of morphological structures

Answer 23

patterns of gene expression

Question 24

general transcription factors

Answer 24

recognizes sequences in the gene promoter

Question 25

enhancer

Answer 25

regulatory elements on DNA that control gene expression; can be located far away upstream or downstream from promoter; DNA sites to which activators bound

Question 26

transcription factor

Answer 26

recognize enhancers; have homeodomain, Leucine zipper, or zinc finger

Question 27

how transcription factors work

Answer 27

recruit mediators that facilitate or impede interaction between RNA polymerase II with general transcription factors; mediate changes in chromatin structure

Question 28

methods of changing chromatin structure

Answer 28

changes in chromatin packing and changes in histone modification

Question 29

master regulators

Answer 29

transcription factors that can initiate a complete development program by themselves; are necessary and sufficient to drive development; function by binding regulatory elements at different genes

Question 30

example of master regulator

Answer 30

eyeless

Question 31

methods of cell memory

Answer 31

positive regulatory feedback, regulatory cascades, epigenetic changes - DNA methylation and histone modification

Question 32

epigenetic inheritance

Answer 32

transmission of epigenetic changes - DNA methylation and histone modification - through cell generations or organism to its descendants