Prenatal Development

Question 1

3 Periods of Prenatal Development

Answer 1

Preimplantation, Embryonic, Fetal

Question 2

Preimplantation

Answer 2

1st week
Sperm + ovum = zygote
*trisomy 21: Down syndrome

Question 3

Embryonic Period

Answer 3

2-8 weeks
Blastocyst > embryo
“Patterning”
*treacher Collins syndrome, rubella, FAS, spins bifida, ectoderm all dysplasia

Question 4

Fetal Period

Answer 4

9 weeks+
Embryo > fetus
*tetracycline stain

Question 5

Induction

Answer 5

Cells establish pathways for tissues

Question 6

Proliferation

Answer 6

Controlled cellular growth and accumulation of byproducts

Question 7

Differentiation

Answer 7

Change in cells to become distinct

Question 8

Morphogenesis

Answer 8

Specific tissue structure/form develops

Question 9

Maturation

Answer 9

Adult function/size attained

Question 10

Cleveage

Answer 10

Zygote undergoes mitosis and splits into more and more cells after fertilization

Question 11

Teratogens

Answer 11

Environmentally caused abnormalities:

Drugs, Chemicals, Infections, Radiation

Question 12

Ectoderm

Answer 12

Comes from epiblast later of bilaminar disk

Question 13

Mesoderm

Answer 13

epiblasts migrate to hypoblast layer comes from migrated mesenchyme cells

Question 14

Endoderm

Answer 14

Comes from hypoblast layer of bilaminar disk

Question 15

Oropharengeal Membrane

Answer 15

Cephailic end (head) of trilaminar disk - no mesoderm (Embryonic period)

Question 16

Neuroectoderm

Answer 16

Specialized differentiated cells begin the CNS of embryo

Embryonic period

Question 17

Gastrulation

Answer 17

Establishes germ layers