Exam 3 Final lecture notes

Question 1

What are the steps of Translation

Answer 1

1) Initiation
2) Chain Elongation
3) Termination

Question 2

Define Initiation

Answer 2

Ribosome binds to mRNA and to the Initiator tRNA.

Question 3

What is the start codon?

Answer 3

AUG

Question 4

Define the process of Chain Elongation

Answer 4

1) once the initiation complex is formed, the next codon is exposed in ribosome
2) the next tRNA (with amino acid) binds to that codon
3) peptide bond is formed between the amino acid
4) the first tRNA detaches and exits
5) the ribosome moves down the mRNA and exposes the next codon.

Question 5

What happens in Termination?

Answer 5

The ribosome reaches the stop codon (no tRNA). A releasing factor (protein) binds to the stop codon, causing the ribosome mRNA & protein to separate.

Question 6

What is Gene Application?

Answer 6

• may be more than 1 copy of the gene on the chromosome
• have multiple simultanious transcription of a gene
• multiple simultanious translation of mRNA

Question 7

How many genes are in the human body?

Answer 7

20,000

Question 8

What is a gene?

Answer 8

A section of a chromosome that codes for a RNA.

Question 9

What is a coding gene?

Answer 9

It codes for a protein

Question 10

What is a non-coding protein?

Answer 10

Does not code for a protein

Question 11

What are the parts of Post Transcription Modification of mRNA?

Answer 11

• Poly ademylation
• splicing
• alternative splicing

Question 12

Define Polyademylation

Answer 12

The addition of Adenines to the end of mRNA (after stop codon).

Question 13

Define splicing

Answer 13

The removal of the introns from the mRNA to make functional mRNA.

Question 14

What are introns?

Answer 14

Introns are short sections of the mRNA that get removed

Question 15

What are Exons?

Answer 15

Short sections of the mRNA that stay in.

Question 16

Define Alternative splicing

Answer 16

It is the unique combination of exons to produce a unique protein.

Question 17

2% of DNA is?

Answer 17

Genes

Question 18

What is part of Regulatory DNA?

Answer 18

Psuedo genes

Question 19

What are psuedo genes?

Answer 19

Nonfuction genes that are remnents from ancestors

Question 20

Where is the GULD psuedo gene found?

Answer 20

In mammals

Question 21

What does GULD do?

Answer 21

Produces enzymes for vitamin C synthesis

Question 22

8% of DNA is?

Answer 22

Endogenous Retrovial DNA

Question 23

What is a virus?

Answer 23

A protein capsul containing genetic material capable of injecting that material into a host cell, making more of the virus.

Question 24

What is the process of DNA Virus?

Answer 24

Insert DNA -> transcribed -> translated -> more virus

Question 25

What is the process of Retrovirus?

Answer 25

inserts mRNA into host and Reverse Transcriptase. mRNA --> sections of DNA - This DNA is incorperated into host DNA

Question 26

What does the retrovirus make?

Answer 26

A provirus

Question 27

What are the characteristics of a provirus?

Answer 27

dormant until triggered. When triggered, it makes more of the virus, which then kills the host.