Lecture 7

Question 1

An interaction between two similarly sized molecules will result in a?

Answer 1

Lesser change in stability.

Question 2

Active site in an enzyme?

Answer 2

The area where the substrates fits in.

Question 3

The substrate of an enzyme?

Answer 3

It

Question 4

Why to enzymes need to be folded up correctly?

Answer 4

To bring all the active sites together.

Question 5

Allosteric proteins?

Answer 5

The shape of a protein can be controlled by the cell by attaching to that protein and changes its shape, somewhere other than the active site.

Question 6

phosphodiester bond?

Answer 6

When two of the hydroxyl groups in phosphoric acid reacts with hydroxyl groups on other molecules to form two ester bonds.

Question 7

RNA vs DNA?

Answer 7

•2’ OH RNA instead of 2’H DNA
•Uracil RNA instead of thymine DNA.
•A ribose sugar group RNA instead of a deoxyribose DNA.

Question 8

Which interaction contributes to DNA stability?

Answer 8

Base stacking by ID-ID interactions.

Question 9

Why do major grooves exist that exposes the interior of the DNA?

Answer 9

To be able to read the information along the DNA without pulling the strands apart.

Question 10

Sigma Factor?

Question 11

Transcription Factor?

Question 12

RNA Polymerase?

Answer 12

Synthesizes RNA from a DNA template strand from the 5’ to 3’ end.

Question 13

How does the 2’ carbon differ in DNA vs RNA?

Answer 13

There is no oxygen in the 2’ carbon in DNA and will not form a hydroxyl group while it will in RNA.

Question 14

What does a gene contain?

Answer 14

A promotor, an RNA coding sequence, and a terminator.

Question 15

A gene is read by?

Answer 15

RNA polymerase that reads from the 3’ to 5’ end. It starts in the promoter sequence.

Question 16

What direction do base building occur?

Answer 16

From the 5’ to 3’ end.

Question 17

Downstream?

Answer 17

The direction that the polymerase moves.

Question 18

Upstream?

Answer 18

The other side of the direction of polymerase.

Question 19

Where does RNA polymerase bind to?

Answer 19

The sigma factor on the promotor.

Question 20

Where in the template strand does transcription start?

Answer 20

In the first +1 nucleotide.

Question 21

Sigma factor?

Answer 21

To find the promotor and bind directly do it and waits for the RNA polymerase to come.

Question 22

The region of a promoter in bacteria?

Answer 22

-10 box and -35 box.

Question 23

RNA polymerase always moves towards?

Answer 23

Downstream towards the 3’ region of the template strand.

Question 24

Why is it important that the sigma factor is not-symmetrical?

Answer 24

It knows the difference between the -35 and -10 box, so it can properly orientate itself .

Question 25

The region of the promotor in eukaryotes is?

Answer 25

The -35 to the TATA box (-10).

Question 26

Are there sigma factors in eukaryotes?

Answer 26

No, it takes about 30 proteins to do the same job.

Question 27

The Job of the terminator is to?

Answer 27

Stop RNA polymerase from reading past it.

Question 28

Ester bond?

Answer 28

A linkage between an atom that is double bonded to an oxygen atom and that atom bonds with an alkyl or aryl group.

Question 29

RNA transcript is produced by?

Answer 29

Polymerization of ribonucleoside triphosphates.

Question 30

Initiation?

Question 31

Elongation?

Question 32

Termination?

Question 33

How many nucleotides from the 3’ end of the TATA box does transcription begin?

Answer 33

25 nucleotides.

Question 34

How many general transcription factors assemble at the promotor of a gene?

Answer 34

At least 6.

Question 35

Transcriptional activator proteins bind to where?

Answer 35

Enhancers.

Question 36

Mediator complex?

Question 37

Ribonucleotides?

Question 38

Pyrophosphate?

Answer 38

Two phosphate atoms in the form of P-O-P

Question 39

Alternative splicing?

Answer 39

When certain exons are spliced out for RNA variation.

Question 40

Glycosidic bond?

Answer 40

A carbohydrate bonding with another molecule.

Question 41

How do proteins recognize the nucleotides in a DNA strand?

Answer 41

A protein has one order of donors and acceptors while the nucleotide bases has one order of donors and acceptors. They must line up correctly to get together.

Question 42

First level of transcription regulation?

Answer 42

How strongly does the sigma and transcription factors interact with the DNA strands.

Question 43

Strong promotors help?

Answer 43

Easily starts transcription.

Question 44

RNA Processing:

Answer 44

•5’ Capping
•Poly-A Tails
•Splicing of introns

Question 45

Do you shuffle exons?

Answer 45

No

Question 46

In bacteria, where in the RNA strand is the start codon?

Answer 46

Exactly on the active site.