Molecular biology of the cell

Question 1

What is an autosome?

Answer 1

Non sex chromosomes.

Question 2

Which enzyme unwinds DNA as part of transcription?

Answer 2

RNA polymerase.

Question 3

What is the promoter region of a gene?

Answer 3

Where RNA polymerase binds at 5’

Question 4

What are exons?

Answer 4

Regions of DNA which make it into the final transcription.

Question 5

What is added post-translation stop site?

Answer 5

A polyA sequence.

Question 6

What are introns?

Answer 6

Regions of DNA which do not make it into RNA.

Question 7

What is at either end of nuclear RNA? (pre-mRNA)

Answer 7

m7GAC attached at beginning.
PolyA tail at end.

Question 8

How is pre-mRNA processed into mRNA?

Answer 8

Through splicing.
Comes in splice isoforms.

Question 9

Where does translation occur?

Answer 9

Ribosomes.

Question 10

How do amino acids get to the ribosomes?

Answer 10

The use of tRNA.

Question 11

What are the different types of epigenetic regulation?

Answer 11

DNA methylation.
Histone acetylation.
Protein ubiquitylation.

Question 12

What are the different types of transcriptional regulation?

Answer 12

Transcription factors.
Enhancers and repressors.
Steroid hormones.

Question 13

How does transcript processing allow for regulation?

Answer 13

Alternative splicing.
MicroRNA-mediated degradation.
Non-sense mediated degradation.
Capping/polyA/RNA binding proteins.

Question 14

Name a form of translation regulation.

Answer 14

Micro RNA and long-noncoding RNAs.

Question 15

What are the forms of (protein level) post translational regulation?

Answer 15

Phosphorylation.
Glycosylation.
Ubiquitylation/de-ubiquitylation.

Question 16

What are the ways mutations can be acquired?

Answer 16

Inherited:
Follows classic Mendelian inheritance rules.
De novo:
Both parents normal.
Single mutation in sperm or egg transmits to child.
Or mutation occurs in zygote very early in pregnancy.
Somatic:
Child has mutation in early post-zygotic development (present in percentage of cells).
Child has mosaic mutation later in development (affects fewer cells)(somatic does not affect offspring).

Question 17

How are some alleles dominant?

Answer 17

Mutations activate an aberrant function.
OR alters structure.
OR affects proteins which are very sensitive to abundance.

Question 18

How are some alleles recessive?

Answer 18

Mostly mutations which lead to loss of function.