Question

QUESTION 5

1. Primary Down syndrome is a result of which of the following?

   		Inversion
   		meiotic nondisjunction
   		DNA methylation
   		Gene duplication
   		Translocation

QUESTION 6

1. A genomic library contains which of the following sequences of an organismâ s DNA?

   		Exon sequences
   		Intron sequences
   		Promoter elements
   		Enhancers and other regulatory elements
   		All of the above

QUESTION 7

1. When the wild-type form of the retinoblastoma protein is phosphorylated, it

   		releases a transcription factor that promotes the expression of genes required for DNA synthesis.
   		Tightly holds on to a transcription factor that promotes the expression of genes required for DNA synthesis.
   		releases a transcription factor that blocks expression of genes required for DNA synthesis.
   		phosphorylates a transcription factor which blocks expression of genes required for DNA synthesis.
   		inactivates a cyclin-CDK complex.

QUESTION 8

1. Select the main reason why stem cells are considered valuable for medicine

   		Stem cells cannot divide, but can differentiate into other types of cells
   		Stem cells divide, but do not ever differentiate into any other cell type.
   		All stem cells are totipotent.
   		Stem cell can regenerate the damaged section of an organ.
   		All stem cells are unipotent.

QUESTION 9

1. A mutation which negatively impacts the functioning of all cells of the individual's offspring is a ___________ mutation.

   		Somatic
   		neutral
   		silent
   		germ-line
   		Such mutation cannot occur

QUESTION 10

1. Histone modifications that reduce the positive charge and increase acidity of histone proteins _________ the packaging of the chromatin and enhance transcription of the DNA.

   		tighten
   		do not influence
   		loosen
   		reinforce
   		none of the above is true

Answer 1

Answer :

5)

Primary Downs syndrome is by

Gene duplication in chromosome 21.

Trisomy 21.

Familial down's syndrome is by translocation.

6)

All of the above.

Genomic library is made by cloning entire genome.

7)

When retinoblastoma protein is phosphorylated it releases transcription factor increasing DNA synthesis.

Transcription factor released is E2F. This activate G1S CdK.

8)

Stem cells can regenerate damaged portion of an organ.

They are multi potent, totipotent, pleuripotent or unipotent.

9)

Germ line mutation.

There will be mutation in sperm or egg.

So mutation in zygote.

So every cell developing from zygote will have mutation.

10)

Loosen.

Acetylation of histone proteins results in lowering of pH and decreased charge. This loosen DNA. This increases transcription.

This modification is also seen in cancer.