Regulation of Gene Expression Review

Question 1

chromosome

Answer 1

• organized structure of DNA and found in cells
• singular piece of DNA, containing many genes, regulatory elements, and other nucleotide sequences
• also contain DNA-bound proteins to pack DNA and control its functions

Question 2

Does the number of chromosomes have an affect on body size or IQ?

Answer 2

No

Question 3

What is a gene?

Answer 3

Region of chromosomal DNA that can be made into RNA

Question 4

Where is DNA located?

Answer 4

• Nucleus -> combination of both parents

- Mitochondrial -> Mother only

Question 5

What happens to sperm mitochondria after fertilization?

Answer 5

It is destroyed

Question 6

Properties of DNA

Answer 6

• Repeating Deoxyribose of A, T, G, and C
• Phosphate
• Nitrogen Base

Question 7

DNA Structure

Answer 7

• Double Helix
• Right handed -> curves upward to right
• Sugar Phosphates -> backbone; outside of helix
• Bases (A,T,C,G) -> Face inward; form “steps”

Question 8

Purines

Answer 8

Adenine and Guanine

Question 9

Pyrimidines

Answer 9

Cytosine and Thymine

Question 10

Adenine pairs with ______ in DNA

Answer 10

Thymine

Question 11

Guanine pairs with ______

Answer 11

Cytosine

Question 12

Hydrogen bonds between G & C

Answer 12

3 hydrogen bonds

Question 13

Hydrogen bonds between A & T

Answer 13

2 hydrogen bonds

Question 14

To which end of a DNA strand are nucleotides added?

Answer 14

3’ end

Therefore synthesis is 5’ -> 3’

Question 15

What does DNA Polymerase do?

Answer 15

Adds Nucleotides to 3’ end during DNA Replication

Question 16

The lagging strand in DNA replication is grown 3’ -> 5’, but DNA Polymerase only works in 5’ -> 3’. How is this problem solved?

Answer 16

• Okazaki fragments

- Fragments are then joined by DNA Ligase in the 3’ -> 5’ direction

Question 17

Exonuclease

Answer 17

• degrades nucleic acid

- works 3’ -> 5’

Question 18

Mutation types in DNA replication

Answer 18

addition, subtraction, and substitutions

Question 19

Mutations, changes that occur during DNA replication, may be….

Answer 19

• lethal
• silent
• beneficial

Question 20

What is transcription?

Answer 20

• process by which DNA is copied into RNA using RNA Polymerase
• Occurs in 5’ -> 3’ Direction

Question 21

Coding Strand

Answer 21

• Always same strand (3’ -> 5’)

- Used to generate RNA Strand

Question 22

Non-coding Strand

Answer 22

RNA sequence will be the same as this sequence

Question 23

promotor

Answer 23

region of DNA that initiates transcription of a particular gene

Question 24

Adenine binds to _______ in RNA

Answer 24

Uracil (U)

Question 25

How does transcription termination occur in bacteria?

Answer 25

Hair-pin Loop

Question 26

Where does RNA Processing occur? What does it result in?

Answer 26

- Occurs in Nucleus | - Results in mature RNA Strand

Question 27

Capping

Answer 27

RNA Process that adds a cap to the 5' end of primary RNA

Question 28

Poly-A Tail

Answer 28

- Added to the 3' end of RNA - protects mRNA from degradation by exonucleases - essential for transcription termination, export of mRNA from nucleus, and for translation

Question 29

Introns

Answer 29

- non-coding regions of a gene - NOT present in mature RNA Transcript - Removed in nucleus

Question 30

Exons

Answer 30

- coding regions of a gene | - can be spliced

Question 31

tRNA

Answer 31

- transfer RNA - binds one specific amino acid - each recognizes 1 or more mRNA sequence (genetic code)

Question 32

rRNA

Answer 32

- ribosomal RNA - along with protein, makes up ribosomes - orients mRNA, tRNA, and amino acid complex - ensure accurate reading of genetic code

Question 33

mRNA

Answer 33

- messenger RNA - contains info for translation into proteins - very high turnover rate - allows for amplification of genetic message through multiple copeis

Question 34

Translation

Answer 34

conversion of mRNA into Protein

Question 35

A Site (Aminoacyl)

Answer 35

binds newly arriving tRNA

Question 36

P Site (Peptidyl)

Answer 36

carries the growing peptide chain attached as a peptidyl-tRNA complex

Question 37

E Site (Exit)

Answer 37

tRNA exit from ribosome

Question 38

Ribosome reads the mRNA sequence to determine the amino acid sequence. It reads 3 nucleotides at a time. What are the 3 nucleotides refer to as?

Answer 38

Triplet Codon

Question 39

How many codons are possible?

Answer 39

64 possible codons

Question 40

Start Codon

Answer 40

AUG -also codes for Methionine

Question 41

Stop Codons

Answer 41

- UAG - UGA - UAA

Question 42

What is glycosylation?

Answer 42

- enzyme-directed site-specific process (glycosyltransferases) - occurs in ER and Golgi apparatus - Folding, targeting, and function of the protein - donor molecules: nucleotide sugars (ex- ADP-glucose) - acceptor residues: asparagine (N), serine (S), and theronine (T)

Question 43

3 Steps of PCR

Answer 43

- Denaturation = separates DNA strands - Annealing = primers bind DNA - Extension = new DNA synthesized

Question 44

Oswald Avery proved that DNA contains the genetic info by studying transformation of...

Answer 44

Bacteria

Question 45

Actinomycin D is an inhibitor of...

Answer 45

Transcription

Question 46

What genetic disease is caused by mutations that disrupt alternative splicing sites?

Answer 46

IGHD2 (Familial isolated growth hormone deficiency type 2)

Question 47

Most abundant protein in the animal body?

Answer 47

Collagen

Question 48

Supravalvar aortic stenosis is caused by ______ gene mutation

Answer 48

Elastin

Question 49

Adherens junctions use _______ to form the focal contact between 2 adjacent cells

Answer 49

Integrins

Question 50

____-actin is muscle specific

Answer 50

Alpha-actin

Question 51

Toll-like receptors are analogues of ________ in vertebrate innate immune systems

Answer 51

IL-1

Question 52

Alpha 1-anti trypsin deficiency causes what in dogs?

Answer 52

Panniculitis

Question 53

Which TLR recognizes LPS?

Answer 53

TLR 4

Question 54

What is LPS?

Answer 54

Lipopolysaccharide - a component of (mostly gram-negative) bacteria cell walls

Question 55

Which TLR recognizes flagellin?

Answer 55

TLR 5