FOM 6.1.2

Question 1

Name for the cell stage that contains 16-32 cells?

Answer 1

Morula

Question 2

What differentiates the blastocyst from the morula?

Answer 2

Presence of the blastocoel (blastocyst cavity)

Question 3

What are two cell types within the bilaminar embryo of the blastula?

Answer 3

Hypoblast and Epiblast

Question 4

From which of the bilaminar embryo regions do mesenchyme cells orginate?

Answer 4

Epiblast

Question 5

What are the three stages of prenatal development most important to an embryologist?

Answer 5

1) Period of ovum - Fert to implant 2) Embryonic Period - implant to 8th wk 3) Fetal Period - 9th wk to birth

Question 6

Name (as many as can off the top of your head, if you make an acronym… please email it me @ tgreiving2@kumc.edu) the fundamental processes and concepts of development.

Answer 6

Cell division and cell cycle, cell adhesion, gene activation, restriction and determination, induction, differentiation, morphogenesis, intercelluar communication, cell movement (evag vs invag), apoptosis, regeneration, growth, heredity and enviroment

Question 7

What process is an essential part of growth during development of fetus and following birth?

Answer 7

Proliferation (cell division)

Question 8

What molecules and related regulatory molecules in cell cycle control are important in development as well as cancer therapies?

Answer 8

Cyclins (phase-controlling)

Question 9

What are 3 examples of cellular adhesion?

Answer 9

sponge cells, cell of same germ layer, mixed tissue

Question 10

What happened over time when red and purple sponge when sponge cells were mixed in a petri dish?

Answer 10

The red (and purple) cells re-aggregated together into individual subgroups. The concept is like recognizing like.

Question 11

If mix retinal cells and enterocytes from both mice and chicks, how will they re-aggregate?

Answer 11

Retinal cells of both type will aggregate while enterocytes aggregate.

Question 12

What molecule is important for cellular adhesion?

Answer 12

CAM (cellular adhesion molecules)

Question 13

Indicate whether CAM expression is high/low for each stage: aggregation, migration, reaggregation.

Answer 13

agg: high CAM
mig: low CAM
reagg: high CAM

(C’mon, that one was easy)

Question 14

When neural crest cells migrate from the neural crest, they reduce expression of N-CAM. What do they increase expression of and why?

Answer 14

Fibronectin, it’s way paves the migratory pathway

Question 15

In aganglionic megacolon, there are no ganglion present in the colon. What cellular component of the plasma membrane of neural crest cells is expected to decrease?

Answer 15

N-CAM

Question 16

Can phenotypic expression be influenced by the ECM?

Answer 16

Yes

Question 17

What classic experiment by Gurdon illustrates the role of gene activation in development of the zygote?

Answer 17

Dolly the Sheep

Question 18

Depression of genes and and the action of tissue-specific transcription factor play essential roles in what two processes?

Answer 18

organogenesis and histogenesis

Question 19

What are the three stages of potency?

Answer 19

Totipotent: most, can become any cell (lost after division of zygote into 8 cells)

Pluriopotent: multiple cell pathways

Unipotent: one cell lineage

Question 20

Describe the meaning of the synonymous terms restriction and determination.

Answer 20

Limiting the proportion of the genome expression by a particular population of cells.

Question 21

What does morphogenesis refer to?

Answer 21

Processes that establish internal and external arrangement of organs or whole or part of an embryo (what makes a hand into a hand, brain into a brain)

Question 22

What is induction?

Answer 22

The process by which the embryonic region interacts w/ a 2nd region to cause the latter tissue to differentiate in a direction it otherwise would not (X -> Y -> P)

Question 23

What is primary induction?

Answer 23

Key interaction in which the dorsal mesoderm induces ectoderm to differentiate into neural structures

Question 24

What is Secondary Induction?

Answer 24

Proximate tissue interactions: action as close range (epithelial-mesenchymal interactions)

Question 25

What is a perfect example of induction within the body?

Answer 25

Respiratory vs. Digestive development from endoderm

Question 26

Evagination vs. Invagation

Answer 26

Evagination: outpocketing of cells (eye development)

Invagination: ingrowth of a sheet of cells (gland development

Question 27

Cell-cell interactions and communication is done via what cellular component?

Answer 27

Gap junctions and junctional complexes

Question 28

What notable physiological feature is apoptosis accountable for?

Answer 28

Seperation of digits (fingers and toes webbed until apoptosis eliminates the webbing)

Also, destruction of overexuberant prod of neurons and axons

Question 29

What is regeneration?

Answer 29

Replacement of already differentiated body parts. (Humans suck at it, even doctors)

Question 30

What is responsible for the secondary induction of the endodermal tube?

Answer 30

Mesenchyme

Question 31

When does the bilaminar embryo develop into the trilaminar embryo? What its alternative name?

Answer 31

Epiblast produces mesenchyme cells. Alt name: Gastrula

Question 32

What is the role of FGF in branching morphogenesis?

Answer 32

Look at pic