Topic.3.Cell.Determination&Stem.cells.powerpoint.3.o

Question 1

T/F A multicellular organism is able to arise due to cells that have different genomes

Answer 1

False, differences between cells come from gene expression differences NOT different genomes

Question 2

Nearly all cells have ___

Answer 2

genomic equivalence

Question 3

SCNT stands for

Answer 3

somatic cell nuclear transfer

Question 4

What discovery was made from the nuclear transplantation in frogs?

Answer 4

The transplanted nucleus of a less differentiated cell can support normal development of egg

Question 5

Explain what happened in Dolly experiment

Answer 5

1.mammary cells nutrient deprived to induce de-differentiation
2.cells fused with enucleated egg from donor sheep
3.mitosis stimulating inducers to form embryos
4. embryo placed in surrogate

Question 6

What can we infer as the reasoning for Dolly the sheep arthritis?

Answer 6

cells could have aged prematurely due to incomplete reprogramming to totipotent stem cells

Question 7

What are some problems associated with animal cloning?

Answer 7

-a small percentage of cloned embryos actually develop into the organism
-cloned mice: premature death, obesity, liver failure, pneumonia

Question 8

What are two mechanisms of epigenetics?

Answer 8

Histone modification(Ex: histone acetylation)
DNA methylation

Question 9

Explain histone modification

Answer 9

It’s a covalent post translational modification(PTM) to histone proteins such as methylation/acetylation

Question 10

Histone modification can impact gene expression by_

Answer 10

altering chromatin

Question 11

T/F epigenetic alter the underlying DNA sequence

Answer 11

Don’t alter it, but add stuff to it that affect how genes are expressed

Question 12

Why are epigenetic changes important in cloning?

Answer 12

In order to reverse a differentiated cell into a totipotent cell, one must revert epigenetic changes

Question 13

Acetylation/methylation are important in _ and _ during development

Answer 13

gene expression and repression

Question 14

How does methylation result to low efficiency of cloning?

Answer 14

Cloned embryos have more methylation than normal embryos, which means cells from nuclei are not completely differentiates

Question 15

Stem cells

Answer 15

stem cell is a relatively unspecialized cell that can reproduce itself indefinitely and differentiate into
specialized cells of one or more types

Question 16

What are the three types of stem cells:

Answer 16

totipotent stem cells
Pluripotent stem cells
Multipotent stem cells

Question 17

Totipotent:

Answer 17

ability to give rise to every type of cell in the
adult body. A zygote is totipotent

Question 18

Pluripotent:

Answer 18

Pluripotent: can form many different cell types

Question 19

T/F Embryonic stem cells (ESC) are totipotent

Answer 19

False:
Embryonic stem cells (ESC) are pluripotent

Question 20

t/F Cells taken from inner cell mass are totipotent

Answer 20

false:
ESC are cells taken from the inner cell mass of the blastocyst, meaning they will never become the trophoblast. Meaning they are pluripotent

Question 21

Multipotent:

Answer 21

Multipotent: ability to differentiate is limited to a few cell
types (eg., bone marrow cells)

Question 22

Order multipotent/totipotent/pluripotent

Answer 22

pluripotent-totipotent-multipotent

Question 23

In the umbilical chord we can expect to find _ which can be used for__

Answer 23

multipotent cells, bone marrow transplant

Question 24

What should we know about vitro fertilization?

Answer 24

when totipotent cells become blastocyst, we can remove inner cell mass that have pluripotent cells(ESC)

Question 25

What should we know about therapeutic cloning?

Answer 25

Involves somatic cell nuclear transfer, taking nucleus from the same person allows, ESC will not reject it, can keep ESC undifferentiated by adding chemicals