Lecture 13 Transcription

Question 1

What is the most accurate description of transcription?

Answer 1

DNA sequence is used to make an RNA

Question 2

What does RNA polymerase bind to during the initiation phase of transcription in prokaryotic cells?

Answer 2

Promoter

Question 3

Which statement best describes the initiation of transcription in eukaryotes?

Answer 3

Transcription factors bind to the TATA box

Question 4

A Gene is…

Answer 4

• A specific stretch of DNA
• basic unit of information storage
  *expressed to make a product

Question 5

DNA is made of…

Answer 5

Deoxyribose
Double-Stranded
4 bases
- Adenine
- Cytosine
- Guanine
- Thymine

Question 6

RNA is made of…

Answer 6

Ribose
Usually Single-Stranded
4 bases
- Adenine
- Cytosine
- Guanine
- Uracil

Question 7

For DNA to be expressed, they must be accessed at the ______ Level

Answer 7

Molecular

Question 8

Transcription is…

Answer 8

*creation of an RNA strand from DNA segment
*Use of DNA as a template
* Makes RNA version of strand (base pairing)

Question 9

Initiation is…

Answer 9

*protein binding to promoter

Question 10

Elongation

Answer 10

Synthesis of RNA

Question 11

Termination

Answer 11

*release of RNA transcript
*detachment of RNA polymerase

Question 12

RNA Polymerase…

Answer 12

*opens up DNA
*synthesizes RNA molecule
* does not need primer to add nucleotides

Question 13

Bacterial mRNAs can be translated into polypeptides as….

Answer 13

soon as they are made

Question 14

Eukaryotic mRNAs are made in…

Answer 14

a longer pre-mRNA molecule which requires further processing to become a mature-mRNA

Question 15

Splicing…

Answer 15

removal of introns and addition of exons

Question 16

introns…

Answer 16

transcribed but not translated

Question 17

exons…

Answer 17

sequence found in matureRNA

Question 18

Human Telomere

Answer 18

• Repeat of GGGTTA.
• Repeated more than 1000 times at each
  telomere.

Question 19

Why do prokaryotes note have telomeres

Answer 19

they have circular chromosomes

Question 20

Mutation is…

Answer 20

• Heritable changes in DNA
• Errors during replication one source of
  mutations
• Eukaryote DNA polymerase has error-
  checking ability
  – 1 error per 1-10 billion base pairs
  – 0.6-6 errors per replication in humans

Question 21

Reverse transcription

Answer 21

transcription of DNA from RNA using an enzyme, common in viruses

Question 22

Central dogma occurs…

Answer 22

in the cell
-transcription and RNA processing in nucleus
-translation outside of nucleus

Question 23

Types of RNA

Answer 23

• Messenger RNA (mRNA)
• Ribosomal RNA (rRNA)
• Transfer RNA (tRNA)

Question 24

Transcription in Prokaryotes…

Answer 24

• One RNA Polymerase
• RNA Pol binds to
  promoter
  ‒ Transcription factors also
  involved
• No processing of mRNA

Question 25

Transcription in Eukaryotes…

Answer 25

• Multiple RNA
  Polymerases
• Transcription factors
  bind to promoter
  ‒ TATA box
• RNA Pol binds to
  transcription factors to
  bind to DNA
• Initial transcript
  processed to form
  mature mRNA