Development of nervous system

Question 1

What develops from ectoderm?

Answer 1

• The CNS and the PNS from the dorsal Ectoderm
• the epidermis

Question 2

What develops from the mesoderm

Answer 2

• Bones
• reprodutive organs
• Kidneys
• muscule
• vascualr system

Question 3

what develops from the endoderm

Answer 3

intsetines

lung

liver

Question 4

Describe the first indication of the nervous system (and times)

Answer 4

on the 16^th day after fertilization,the neuroectoderm consisting of the neural plate,appears on the dorsal midline of embryo.

.its cells are taller then other ectoderm cells (induced by the underlying mesodermic cells )

in two days the neural plate grow rapidly and becomes a neural groove neural folds,its raised latterl edges

Question 5

what it T0 in pregnancy

Answer 5

a) in clinical terms – 1^st day of last period (about 14 days before fertilization)
b) the age of embryo is the estimated date of fertilization

when embryo is 8 weeks old (and all organs are formed) it

is renamed fetus

Question 6

what are Carnegie stages

Answer 6

Embyonic development ( 8 weeks from fert) is divide to 23 stages Germinal stage (first 2 weeks post fert) Embryonic period (wks 2-8)

Taking into consideration correlation between age, size and its morphologic characteristic of embryonic development

Question 7

when are the neural folds formed (what Carnegie stage) and what are they? (location)

Answer 7

neural folds,are theraised latterl edges neural groove

at stage 8 when embryo is 1-1.5 mm long