Class 12:

Question 1

Developmental potency/potential totipotent:

Answer 1

Able to give rise to all cells.

Question 2

pluripotent

Answer 2

only able to give rise to some cells, not all

Question 3

differentiated

Answer 3

Having a distinct transcriptome resulting in specialized cell functions. Regulated by a. whether the gene is active or silent (transcribed or not) b.cellular signals c. transcription factors (respond when activated by cell signal)

Question 4

Barker Hypothesis:

Answer 4

Poor maternal nutrition resulted in poor fetal growth in utero and low birth weight. Led to metabolic issues later in life: Cardiovascular disease, type 2 Diabetes, Obesity.

Question 5

Thrifty phenotype:

Answer 5

The result of the aforementioned poor maternal nutrition. Scarce resources in utero resulted in cellular reprogramming, developing a low metabolic rate as an adaption to the poor nutrition utero with anticipation of the same upon birth. But abundant resources actually available resulting in development of obesity, Diabetes, Cardiovascular disease.

Question 6

Epigenetic programming of gene expression; implications for differential gene expression:

Answer 6

can result in change in the transcriptome therefore change in the differential gene expression.

Question 7

Promoter of a gene:

Answer 7

Region of DNA where Transcription factor binds to initiate transcription of DNA to RNA.

Question 8

DNA methylation

Answer 8

Binding (or methylation) of nucleotides in the Promoter region resulting in activation or silencing of the gene.

Question 9

Imprinting

Answer 9

A specific type of epigenetic programming. Gene expression is based on whether mother or father’s inherited copy is silenced or activated. In these particular genes only one of either the father’s or mother’s will be “imprinted” or methylated (silenced in this case). Errors can occur when the wrong parents gene has been imprinted or both are imprinted.

Question 10

Beckwith- Wiedemann Syndrome (Large Offspring Syndrome):

Answer 10

At increased risk if from IVF. Thought to be due to error in imprinting resulting in overgrowth: large tongue, enlarged organs, low blood sugar, >cancer risk. This is a an example of a less extreme case of abnormality in imprinting.

Question 11

Methyl-rich or methyl-deficient diet:

Answer 11

Restricting the nutrients that aid in methylation resulted in higher fat mass, lower lean body mass, insulin resistance, and high blood pressure in adult males (did not seem to affect females). This study was done with changes in Maternal Diet.

Question 12

Paternal diet

Answer 12

Also demonstrated ability to change gene expression/ physiological processes in adult offspring.