3.7 Development of multicellular organisms

Question 1

Genome of all cells in an organism are

Answer 1

identical

Question 2

Expression of genes is

Answer 2

different

Question 3

What are the 4 major phases in development?

Answer 3

Cell division, cell differentiation, cell interaction. cell migration

Question 4

Genes expressed by cell depend on what?

Answer 4

Environement both present and past

Question 5

Homologous proteins are functionally what?

Answer 5

interchangeable

Question 6

What is a blastula?

Answer 6

Ball of cells surrounding a hollow cavity

Question 7

What is a gastrula?

Answer 7

Blastula that undergoes rearrangements, 3 major layers.

Question 8

What does the blastula consist of ?

Answer 8

Sheet of epithelial cells

Question 9

What is the ectoderm?

Answer 9

previrsor of nervous system and epidermis

Question 10

What gives rise to the ectoderm?

Answer 10

the blastula

Question 11

What gives rise to the endoderm?

Answer 11

ectoderm

Question 12

The endoderm is the precursor of what 3 things?

Answer 12

Gut, lung, liver

Question 13

What gives rise to the mesoderm?

Answer 13

The group of cells that move inbetween ectoderm and endoderm

Question 14

Mesoderm is precursor to what?

Answer 14

muscle and connective tissue

Question 15

What the definition of gastrulation?

Answer 15

Transformation of the blastula into a layered structure with a gut.

Question 16

What do fruit flys and humans have in common?

Answer 16

Homologs

Question 17

What is the most important for development?

Answer 17

gene regulatory proteins

Question 18

What holds the instruction for producing a multicellular animal?

Answer 18

non coding regulatroy DNA

Question 19

What serve as binding sites for gene regulatory proteins?

Answer 19

Regulatory elements

Question 20

What sequence are similar in most organisms

Answer 20

coding sequences

Question 21

What sequences make one organism dif from another?

Answer 21

non coding sequences

Question 22

What comes first? Developmental decisions or differentiation?

Answer 22

Developmental decisions

Question 23

What are determined cells?

Answer 23

Cells that are fated to develop into a specialized cell type despite changes in environment

Question 24

What are completely undetermined cells?

Answer 24

Cells that can change rapidly due to alteration in environment

Question 25

What are committed cells?

Answer 25

Cells that have some attributes of a particular cell type but can change with environment.

Question 26

Position specific character of cell is called what?

Answer 26

positional value.

Question 27

How can cells become different?

Answer 27

Asymmetric division

Question 28

How can cells born the same can become dif?

Answer 28

Change in environment after birth

Question 29

What is the most important environmental cues?

Answer 29

Signals from neighboring cells

Question 30

What is inductive signaling?

Answer 30

Induction of a dif developmental program in select cells in a homogenous group leading to altered character

Question 31

What are short range signals?

Answer 31

cell to cell contact

Question 32

What are long range signals?

Answer 32

substances that can diffuse through the extracellular medium

Question 33

What is a morphogen?

Answer 33

a long range inductive signal that imposes a pattern on a field of cells.

Question 34

What 3 main factors are due to diversity in pattern?

Answer 34

Gene duplication, presence of other signals and previous experiences of the cell

Question 35

What is the ultimate result of inductive events?

Answer 35

change in DNA transcription

Question 36

Signaling pathways response depends on what two things?

Answer 36

spatial and temporal expression