Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MED6112 > Early Embryo Metabolism > Flashcards

Early Embryo Metabolism Flashcards

1
Q

In what region of the female reproductive tract does fertilisation occur?

A

Ampulla region of the fallopian tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

At what stage is the embryo first known as a zygote

A

2 cell stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

At what stage does compaction occur?

A

16-32 cell stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How long does compaction last?

A

3 to 4 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

When does the embryo become a blastocyst?

A

Following compaction, when the morula is released in to the uterus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What cell changes define blastocyst stage of embryo development?

A

At blastocyst stage, cells gain developmental competence - stat to form crude cell lineages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the cell fate of outer cells in blastocyst?

A

trophectoderm, due to be placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the cell fate of inner cells in blastocyst?

A

Inner cell mass, due to be fetus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which cellular interaction increases at compaction?

A

cell to cell adhesion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the main mediator molecule of increased cell adhesion at compaction?

A

E-cadherin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What dependency do outer cells gain during polarisation at compaction stage?

A

Calcium dependency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In absence of calcium - will compaction occur?

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What secondary protein allows the binding of e-cadherin to actin cytoskeleten in blastomers?

A

Alpha and beta catenins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

At what stage of embryo development is e-cadherin expressed?

A

expressed from early cleavage, but loacalised to regions of cell to cell contact at compaction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is theory for relocalisation of e-cadherin

A

Driven by PKc (protein kinase C)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What do E-cadherin knockouts, alpha catenin knockouts and embryos treated with e-cadherin antibodies all have in common?

A

They will fail at compaction stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is an occludin?

A

transmembrane protein involved in embryo development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What further proteins exist in occludin complexes?

A

ZO-1, ZO-2 and cingulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

At what cell stage does the biogenesis of tight junctional proteins occur?

A

beginning at 6 - 8 cell stage, up until blastocyst formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Where are TJPs polarised to?

A

Apical face of cells.

21
Q

What allows embryos to go from permeable to sealed?

A

formation of tight junctions between cells.

22
Q

What is the blastoceole?

A

Area of water (and some other factors) found in the middle of the blastocyst

23
Q

Via what mechanism does the blastoceole increase in size?

A

Due to a sodium gradient, water flows in to the embryo.

Synonymously, tight junctions are being formed, and water is retained in the embryo. Cells become impermeable

24
Q

What are the two main hypotheses for cell polarization in early embryo development?

A

Inside/Outside hypothesis and Cell Polarity hypothesis

25
Q

What is the main difference between the 2 hypotheses for cell polarisation in early embryo development?

A

Inside/outside hypothesis assumes that cell division determines the cell fate. Cell Polarity hypothesis assumes that cell fate determines the direction of cell division.

26
Q

Where can Oct4 be found in the blastocyst

A

Inner cell mass

27
Q

How is Oct4 localised?

A

Oct4 expression is repressed by Cdx2, found localised to trophectoderm

28
Q

What about the location where Cdx2 is found is special?

A

At the apical domain of cells where Cdx2 is found, there are exposed cell faces. In all other cells in the blastocyst, there is isometric binding - connected at all faces.

29
Q

Where can Nanog be found in the blastocyst

A

salt and peppered in Inner cell mass

30
Q

Where can Gata6 be found in the blastocyst?

A

Salt and peppered in inner cell mass (not in same cells as nanog)

31
Q

How does Grb2 regulate Nanog and Gata6?

A

Grb2 inhibits Nanog expression and promotes Gata6 expression.

32
Q

In early cleavage embryo, what is the main energy substrate?

A

pyruvate

33
Q

Up until compaction, what is the main mechanism for energy production in the embryo?

A

TCA cycle (Krebs cycle)

34
Q

During and after compaction, what is the main mechanism for energy production in the embryo?

A

glycolysis

35
Q

At what point of embryo development would you expect to see lactate production increase?

A

compaction

36
Q

what mechanism do cumulus cells utilise to provide energy substrate for the oocyte?

A

glycolysis (to produce pyruvate)

37
Q

What is the main product of the PPP pathway in cumulus cells?

A

NADPH

38
Q

What is the main effect of the accumulation of ATP in early embryo? (other than use for energy)

A

Disrupts the ATP:ADP ratio having a negative impact on the production of phosphofructokinase (PFK), so glycolysis cannot occur.

39
Q

How is the ATP:ADP ratio restored?

A

use of ATP for high energy processes eg compaction

40
Q

Other than glycolysis, what is glucose used for in the embryo?

A

basic material required for nucleic acid synthesis, required for phospholipid and non essential amino acid biosynthesis.

41
Q

What are glucose transporter proteins known as?

A

GLUT

42
Q

When is GLUT4 expressed?

A

Only expressed from blastocyst stage onwards

43
Q

When is GLUT5 expressed?

A

GLUT5 expression begins at 8 cell stage

44
Q

Are embryos that have high glucose uptake more or less likely to be viable?

A

More likely

45
Q

Are embryos that have high rates of glycolysis more or less likely to be viable?

A

Less

46
Q

what effect does culturing embryos in high oxygen concentration have?

A

toxic

47
Q

High production of alanine at early embryo stages can be an indicator of what?

A

embryo arrest

48
Q

What will happen to embryos which have high metabolic activity and use of amino acids at very early stages?

A

they will fail :( (metabolic stress)

MED6112 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions