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Question 1

ectoderm

Answer 1

the epidermis of the skin
nervous system
teeth and jaws
germ layer
adrenal medulla
sweat glands
hair follicle
the pituitary gland

Question 2

Mesoderm

Answer 2

dermis of the skin
the skeletal system
muscular system
adrenal cortex
excretory system
reproductive ( except germ layer)
the lymphatic system

Question 3

endoderm

Answer 3

epithelia of the digestive tract and associated organs
epithelial of respiratory and excretory and reproductive tract and ducts
thymus
thyroid
parathyroid

Question 4

body cavity

Answer 4

coelomates
pseudocoelomate
acoelomate

Question 5

coelomates

Answer 5

cavity covered with mesoderm

annelids

Question 6

pseudocoelomate

Answer 6

cavity covered with meso and endo

nematoda

Question 7

acoelomates

Answer 7

cavity filled with mesoderm
platyhelminthes
`

Question 8

protostome

• cleavage
• coelom formation
• fate of blastopore

Answer 8

molluscs
annelids

cleavage:

• spiral : planes of cell diagonal to vertical axis
• determinate : developmental fate of each cell determined

coelom formation
solid masses of cell split to form coelom

fate of blastopore
mouth

Question 9

deuterostome

• cleavage
• coelom formation
• fate of blastopore

Answer 9

echindermes
chordates

cleavage;

• radial : cleavage planes are parallel or perpendicular to vertical axis
• indeterminate; each cell can develop into fully formed and functional cell

coelom formation
mesoderm pinches off archenteron to form coelom

fate of blastopore
anus