Cleavage

Question 1

is a rapid series of mitotic divisions that occur just after fertilization

Answer 1

cleavage

Question 2

During the process of cleavage ,the cell cycle consists of only 2 phases

Answer 2

s-phase dna synthesis
m-phase

Question 3

The cell in cleavage does not go through a ______

Answer 3

g1, g2 phases

Question 4

In the mammals’ ova the first cleavage stage takes ______ which is the lowest
eggs in the yolk.

Answer 4

24 hours

Question 5

In the embryo of birds completes the stages of cleavage

Answer 5

before the female lays the egg

Question 5

In the amphibians 1st cleavage done within

Answer 5

3 hours

Question 6

cleavage in sea urchin embryo

Answer 6

radial cleavage

Question 7

cleavage in mammals

Answer 7

rotational cleavage

Question 8

do not grow in size between successive cell divisions

Answer 8

blastomeres

Question 9

have a small amount of yolk that is equally
distributed in the cytoplasm (most mammal eggs have this)

Answer 9

isolecithal eggs

Question 10

have a moderate amount of yolk, and the
yolk is present mainly in the vegetal hemisphere (amphibians have this)

Answer 10

mesolecithal eggs

Question 11

have a large amount of yolk that fills the
cytoplasm, except for a small area near the animal pole (fish, reptiles, and
birds)

Answer 11

telolecithal eggs

Question 12

have a lot of yolk that is concentrated within the center of
the cell (insects and arthropods).

Answer 12

centrolecithal eggs

Question 13

occurs in isolecithal eggs (mammals, sea urchins). The
entire egg is cleaved during each division.

Answer 13

holoblastic cleavage

Question 14

occurs when eggs have a lot of yolk. The egg does not
divide completely at each division.

Answer 14

meroblastic cleavage

Question 15

is limited to a small disc of cytoplasm at the animal
pole. All of the yolk filled cytoplasm fails to cleave (characteristic of
telolecithal eggs such as birds)

Answer 15

discoidal cleavage

Question 16

is limited to a thin surface area of cytoplasm that
covers the entire egg. The inside of the egg that is filled with yolk fails to
cleave (centrolecithal eggs such as insects).

Answer 16

superficial cleavage

Question 17

two types of meroblastic cleavage

Answer 17

discoidal cleavage
superficial cleavage

Question 18

1st qnd 2nd cleavage

Answer 18

meridional

Question 19

The 3rd cleavage is

Answer 19

equatorial

Question 20

at the 16 to 32 cell stage the embryo is called a ______ because it looks like a mulberry. Witch will transfer to blastula stage.

Answer 20

morula

Question 21

will form at the end of cleavage stage

Answer 21

blastula

Question 22

Its has a cavity called the _______ between the animal and vegetal pole

Answer 22

blastocoel

Question 23

The outer surface of the amphibian blastula has cells connected by specialized

Answer 23

cell junctions

Question 24

create a seal that isolates the outside of an embryo from the inner layer and polarize the apical and basal surfaces.

Answer 24

tight junctions

Question 25

attach the blastomeres together on the outside.

Answer 25

desmosomes

Question 26

connect all surface blastomeres.

Answer 26

gap junctions

Question 27

The blastula are distributed into 3 areas

Answer 27

animal pole, vegetal pole, and in the middle of blastula

Question 28

will develop to the ectoderm witch will give the neural tube and the skin (epidermis).

Answer 28

animal pole

Question 29

(the lower part of the blastula) will form the endoderm witch will develop and give the elementary canal,lungs

Answer 29

vegetal pole

Question 30

will give the mesoderm that will develop and give the dermis, heart, muscles, bones, kidney.

Answer 30

middle of blastula