General Embryology

Question 1

primordium

Answer 1

earliest indication of a tissue or an organ during prenatal development

Question 2

autocrine regulation of growth factors

Answer 2

growth factor produced by a cell that recaptures its own products

Question 3

paracrine regulation of growth factors

Answer 3

growth factors synthesized by one cell can diffuse over small distances to induce changes

Question 4

endocrine regulation of growth factors

Answer 4

growth factor produced in one cell travels in the blood to distant locations to act on another cell

Question 5

hemeobox genes

Answer 5

involved in bodily segmentation during embryonic development

Question 6

what are two results of the primitive streak?

Answer 6

germ layer formation and bilateral symmetry

Question 7

What type of cells invaginate during gastrulation?

Answer 7

ectodermal cells

Question 8

What happens in the transition of epithelial cells to mesenchyme?

Answer 8

epithelial cells detach from basement membrane and are able to migrate

Question 9

neural plate

Answer 9

central band of cells from cephalic to caudal end. The neural plate thickens and invaginates to form the neural groove

Question 10

morula

Answer 10

solid ball of cells

Question 11

blastocyst

Answer 11

vesicle that implants in the endometrium

Question 12

induction

Answer 12

one group of cells induces another group of cells to change

Question 13

proliferation

Answer 13

control of cellular growth and accumulation of biproducts

Question 14

appositional growth

Answer 14

tissue enlarges its size by the addition of layers on the outside of a structure

Question 15

interstitial growth

Answer 15

growth the occurs deep within a tissue

Question 16

differentiation

Answer 16

change in embryonic cells to become to become distinct structurally and functionally

Question 17

morphogenesis

Answer 17

development of specific tissue structures that lead to increasing complexity of structure and function of cells

Question 18

maturation

Answer 18

attainment of adult function and size

Question 19

ectoderm

Answer 19

epidermis, epithelium, nervous sytem, mammary and cutaneous glands

Question 20

endoderm

Answer 20

respiratory, digestive system lining. live and pancreas

Question 21

mesoderm

Answer 21

dermis, muscles, bone, bone, dentin, blood, cementum, cartilage, reproductive and excritory systems

Question 22

HOX genes

Answer 22

patterning of body axis and anterior posterior polarity

Question 23

DLX Genes

Answer 23

control Proximal and Distal develpment of ectodermal tissues of the branchial arch skeleton

Question 24

what is gastrulation

Answer 24

ectodermal cells invaginate. Mesoblast cells form true embroyonic endoderm and mesoderm.

Question 25

mesenchyme

Answer 25

loose aggregate of unorganized (nonpolar) cells. Can migrate

Question 26

neural plate

Answer 26

central band of cells from cephalic to caudal end. This plate grows and thickens. It becomes deep and invaginates to form the neural groove

Question 27

teratogens

Answer 27

environmental factos (drugs, chemical, infections) - involved in congenital malformations

Question 28

tetracycline

Answer 28

stains teeth

Question 29

syphalis can casue

Answer 29

hutchins incisors or mulburry molars

Question 30

half life of growth factors

Answer 30

very short

Question 31

growth factors are what type of molecule?

Answer 31

peptides

Question 32

calcium dependant cell adhesion molecules

Answer 32

cadherins

Question 33

calcium independant adhesion molecules

Answer 33

cam

Question 34

preimplantation period

Answer 34

1st week after conception - female ovum is penetrated by sperm and is fertilized = zygote

Question 35

final stages of meiosis occur where

Answer 35

during fertilazation, the final stages of meiosis occur in the ovum

Question 36

mitosis produces

Answer 36

diploid cells

Question 37

meiosis produces

Answer 37

haploid cells

Question 38

normal humans have how many chromosomes?

Answer 38

46 (2 haploid cells come together -23 chromosomes each to form a diploid number of 46)

Question 39

down syndrome

Answer 39

trisomy 21, estra chromosome 21 is present after meitotic division