Unit 5: Chapter 21

Question 1

morphogenesis

Answer 1

creation of form

Question 2

cell differentiation

Answer 2

cells become specialized in structure and function

Question 3

genomic equivalence

Answer 3

all cells have the same DNA and the same genes

Question 4

gene expression

Answer 4

a gene is turned on which creates a product that provides some kind of characteristic

Question 5

differential gene expression

Answer 5

some of the genes have been turned off in order to specialize a cell

Question 6

totipotent

Answer 6

a cell that can generate a completely new organism

used in cloning

Question 7

nuclear transplantation

Answer 7

the nucleus of an unfertilized cell or zygote is replaced with the nucleus of a differentiated cell

Question 8

stem cell

Answer 8

unspecialized cell

can reproduce indefinitely and differentiate into specialized cells

embryonic: totipotent
adult: pluripotent

Question 9

pluripotent

Answer 9

can give rise to multiple but not all cell types

Question 10

three things invoked in cell determination and differentiation

Answer 10

transcriptional regulation

cytoplasmic determinants

induction of embryonic cells

Question 11

transcriptional regulation process

Answer 11

determination: cell must decide what it wants to be first

turns on master control gene

this produces mRNA which produces proteins specific to the desired function

genes are turned on like dominoes

Question 12

cytoplasmic determinants

Answer 12

maternal substances in the cell influence early development

affect cell determination

when the cell divides in meiosis, the cytoplasmic determinants end up more concentrated in different halves. this decides what the cell will want to be

Question 13

induction

Answer 13

nearby cells transmit chemicals to other cells through signal transduction pathway which trigger developmental changes

Question 14

positional information

Answer 14

cytoplasmic determinants and induction

tells a cell its location relative to the body axes and neighboring cells

Question 15

pattern formation

Answer 15

the development of a special organization of tissues and organs

Question 16

egg polarity genes

Answer 16

aka maternal effect genes

initially establish the axes of the body

Question 17

bicoid gene

Answer 17

affects the front half of the body

Question 18

how does axis establishment work be

Answer 18

a gradient of diffused substances called morphogens creates areas of different concentrations and cells the embryo which part is the front and the back

Question 19

segmentation genes

Answer 19

produce proteins that cause the formation of segments in the body after axis formation

Question 20

homeotic genes

Answer 20

master regulatory genes that control the anatomical identities of the flies

Question 21

apoptosis

Answer 21

programmed cell death

not always bad

cell shrinks and “blebs”
nucleus condenses
DNA is fragmented

Question 22

three processes of cell development

Answer 22

cell division
morphogenesis
cell differentiation