Exam

Question 1

Intra embryonic mesoderm

Answer 1

When the primitive streak produces mesenchyme cells invaginate and then move laterally and cranially between epiblast and endoblast.

Question 2

Primary germ layer occur at the end of the ……… week

Answer 2

3rd week

Question 3

The site of the future mouth

Answer 3

Pre chordal plate

Question 4

When is the oropharyngeal membrane formed?

Answer 4

When the prochordal plate firmly attaches to the overlying ectoderm

Question 5

Future cite of the anus is

Answer 5

Cloacal membrane

Question 6

Vesicles of the brain are formed when the

Answer 6

The cranial end of the neural plate markedly expands

Question 7

Neurulation

Answer 7

When the neural plate invagites along the midline axis to form a neural groove and paired electrons on either side called neural folds.

Question 8

The slender part of the neural tube caudal to the large cerebral region forms

Answer 8

Spinal cord

Question 9

Yolk sac

Answer 9

Endoderm and mesoderm

Question 10

Amnion

Answer 10

Ectoderm and mesoderm

Question 11

Allantois

Answer 11

Endoderm and mesoderm

Question 12

Chorion

Answer 12

Mesoderm and trophoblast

Question 13

Amnion

Answer 13

The combination of of ectoderm and mesoderm produces a thin extra embryonic membrane

Question 14

Wat is the first extra embryonic membrane to. Develop

Answer 14

Yolk sac

Question 15

The human embryo receives it nutrition from

Answer 15

Endometrium

Question 16

What is the purpose of the yolk sac?

Answer 16

To produce blood cells until the liver is developed n the sixth week.

Question 17

The dorsal portion of the yolk sac contributes to the

Answer 17

Formation of the primitive gut

Question 18

The stalk of the yolk sac usually separates from the gut by the

Answer 18

6 th week

Question 19

Allantois

Answer 19

A small vascular isles sac of endoderm and mesoderm form during the third week as a small outpouching or diverticulitis of the endoderm near the caudal wall of the yolk sac.

Question 20

Purpose Of the allantois

Answer 20

Formation if blood cells and its vessels, connects between the mother and fetus

Question 21

The base of the allantois alters becomes the

Answer 21

Unitary bladder

Question 22

The chorion develops from the

Answer 22

combination of trophoblast and associated mesoderm

Question 23

Villi

Answer 23

Finger like projections develop from the chorion and penetrate deeply into uterine tissue.

Question 24

Smooth chorion

Answer 24

Villi on the surface toward the uterine cavity , which degenerate and produce a smooth bare area

Question 25

Functions of placenta

Answer 25

Respiratory and nutrition support essential for prenatal development