FOM 6.1.2 Flashcards
Name for the cell stage that contains 16-32 cells?
Morula
What differentiates the blastocyst from the morula?
Presence of the blastocoel (blastocyst cavity)
What are two cell types within the bilaminar embryo of the blastula?
Hypoblast and Epiblast
From which of the bilaminar embryo regions do mesenchyme cells orginate?
Epiblast
What are the three stages of prenatal development most important to an embryologist?
1) Period of ovum - Fert to implant 2) Embryonic Period - implant to 8th wk 3) Fetal Period - 9th wk to birth
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.
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
What process is an essential part of growth during development of fetus and following birth?
Proliferation (cell division)
What molecules and related regulatory molecules in cell cycle control are important in development as well as cancer therapies?
Cyclins (phase-controlling)
What are 3 examples of cellular adhesion?
sponge cells, cell of same germ layer, mixed tissue
What happened over time when red and purple sponge when sponge cells were mixed in a petri dish?
The red (and purple) cells re-aggregated together into individual subgroups. The concept is like recognizing like.
If mix retinal cells and enterocytes from both mice and chicks, how will they re-aggregate?
Retinal cells of both type will aggregate while enterocytes aggregate.
What molecule is important for cellular adhesion?
CAM (cellular adhesion molecules)
Indicate whether CAM expression is high/low for each stage: aggregation, migration, reaggregation.
agg: high CAM
mig: low CAM
reagg: high CAM
(C’mon, that one was easy)
When neural crest cells migrate from the neural crest, they reduce expression of N-CAM. What do they increase expression of and why?
Fibronectin, it’s way paves the migratory pathway
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?
N-CAM
Can phenotypic expression be influenced by the ECM?
Yes
What classic experiment by Gurdon illustrates the role of gene activation in development of the zygote?
Dolly the Sheep
Depression of genes and and the action of tissue-specific transcription factor play essential roles in what two processes?
organogenesis and histogenesis
What are the three stages of potency?
Totipotent: most, can become any cell (lost after division of zygote into 8 cells)
Pluriopotent: multiple cell pathways
Unipotent: one cell lineage
Describe the meaning of the synonymous terms restriction and determination.
Limiting the proportion of the genome expression by a particular population of cells.
What does morphogenesis refer to?
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)
What is induction?
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)
What is primary induction?
Key interaction in which the dorsal mesoderm induces ectoderm to differentiate into neural structures
What is Secondary Induction?
Proximate tissue interactions: action as close range (epithelial-mesenchymal interactions)
What is a perfect example of induction within the body?
Respiratory vs. Digestive development from endoderm
Evagination vs. Invagation
Evagination: outpocketing of cells (eye development)
Invagination: ingrowth of a sheet of cells (gland development
Cell-cell interactions and communication is done via what cellular component?
Gap junctions and junctional complexes
What notable physiological feature is apoptosis accountable for?
Seperation of digits (fingers and toes webbed until apoptosis eliminates the webbing)
Also, destruction of overexuberant prod of neurons and axons
What is regeneration?
Replacement of already differentiated body parts. (Humans suck at it, even doctors)
What is responsible for the secondary induction of the endodermal tube?
Mesenchyme
When does the bilaminar embryo develop into the trilaminar embryo? What its alternative name?
Epiblast produces mesenchyme cells. Alt name: Gastrula
What is the role of FGF in branching morphogenesis?
Look at pic
