Day 2, Lecture 2: Genetics: Gene structure-function/Transfer of genetic info

Question 1

What is the Splice donor site

Answer 1

5’ GT/GU on the intron

Question 2

Splice acceptor site

Answer 2

3’ AG on the intron

Question 3

Splicing is a complex process directed by sequence elements at the

Answer 3

5’ (splice donor) and 3’ (splice acceptor) ends of introns

Question 4

Which is longer the distance of the splice donor site to the branch site or the distance of the branch site to the splice acceptor site

Answer 4

• The splice to donor site is 10s to > 10,000 nucleotides long
• Branch site to splice acceptor site is < 20 nucleotides long

Question 5

Role of snRNPs in mediating RNA splicing

Answer 5

Question 6

Question 7

Question 8

Question 9

genetic code is deciphered on ___ via codon-anticodon recognition

Answer 9

ribsomes

Question 10

is it always possible to define a gene as a discrete transcriptional unit

Answer 10

• No
• The final product can have different combinations of genes

Question 11

Alternative splicing

Answer 11

• >50% of human genes use different combinations of exons to produce more than one type of protein.
• A single gene may use different combinations of exons producing more than one type of protein
• May be tissue specific and/or developmental stage specific

Question 12

Differential gene expression

Answer 12

Genes may be expressed in specific tissues and developmental stages

Question 13

_____ results in tissue-specific products of the calcitonin gene

Answer 13

Differential RNA processing

Question 14

Special forms of differential gene expression

Answer 14

• Genetic imprinting
• X-Chromosome inactivation

Question 15

about how many genes are imprinted

Answer 15

only a minority (about 60)

Question 16

Does the XIC (X-inactivation center) mediate chromosome counting for activation

Answer 16

• Yes
• it is able to make sure that there is only one active X chromosome per diploid set of autosomes

Question 17

Heteroplasmy

Answer 17

Each cell may have different numbers of mutant and normal mitochondrial genomes

Question 18

The mitochondrial genome is composed of

Answer 18

a single compact circular chromosome

Question 19

The mitochondrial genome is inherited

Answer 19

maternally

Question 20

How many mitochondrial genes are there

Answer 20

37 genes