cleavage and blastocyst

Question 1

describe the process of cleavage

Answer 1

zygote undergoes series of mitotic divisions into lots of smaller daughter cells

Question 2

what name is given to the small daughter cells made by mitotic division

Answer 2

blastomeres

Question 3

what is meant by the term totipotent and what cells does it refer to

Answer 3

totipotent means that it can differentiate into any cell type, the first 8 blastomere cells are said to be totipotent

Question 4

what is the morulla

Answer 4

the morulla is the name given to the collection of 16+ blastomeres

Question 5

describe the compaction of the morulla

Answer 5

cells confined in zona pellucida maximise space and begin to form cell junctions, outer cells in contact with zona pellucida form gap junctions, fluid enters through the ZP

Question 6

name the different parts of the blastocyst

Answer 6

trophoblast, inner cell mass, blastocyst cavity

Question 7

what is meant by blastocyst hatching

Answer 7

this refers to when the blastocyst breaks through the ZP

Question 8

what does the trophoblast part of the blastocyst give rise to

Answer 8

it attaches to the endometrium lining and becomes the placenta

Question 9

what does the inner cell mass of the blastocyst give rise to

Answer 9

this develops into the body of the embryo