Chapter 5

Question 1

forms the exoskeleton

Answer 1

ectoderm

Question 2

hollow ball of cells that forms as a result of cleavage

Answer 2

blastula

Question 3

mitotic division of an animal cell; divides a zygote’s cytoplasm into smaller blastomeres

Answer 3

cleavage

Question 4

middle tissue layer of a 3 layared animal embryo

Answer 4

mesoderma

Question 5

an adult human has about how many differentiated cell types

Answer 5

200

Question 6

forms the inner lining of organs

Answer 6

endoderm

Question 7

a __ __ forms as microtubules constrict or lengthen in different cells

Answer 7

neural groove

Question 8

type of master gene that controls formation of specific body parts during development

Answer 8

homeotic gene

Question 9

32 cells

Answer 9

morulla

Question 10

the process by which certain body parts form in a specific place or locations

Answer 10

pattern formation

Question 11

the diploid cell that forms at fertilization

Answer 11

zygote

Question 12

chemical encoded by a master gene; diffuses out from its source and affects developmet

Answer 12

morphogens

Question 13

develops into organs

Answer 13

mesoderm

Question 14

fuild-filled cavity in blastula is called

Answer 14

blastocoel

Question 15

outermost tissue layer on an embryo

Answer 15

ectoderm

Question 16

three-layered developmental stage formed by gastrulation

Answer 16

gastrula

Question 17

mechanism of cell suicide

Answer 17

apoptosis

Question 18

accumlation of different materials in different regions of the egg cytoplasm

Answer 18

cytoplasmic localization

Question 19

innermost tissue layer

Answer 19

endoderm