Chapter 7 Flashcards

You may prefer our related Brainscape-certified flashcards:
0
Q

DNA

A

Deoxyribonucleic Acid
Deoxyribose sugar
Bases - Adenine, Thymine, Guanine, Cytosine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Biosynthesis

A

processes that synthesize and assemble macromolecule subunits, use ATP energy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

DNA Structure

A

Double Helix
Sugar-phosphate chains on outside
Complementary base pairing (A-T, G-C) with hydrogen bonds
Two strands run antiparallel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Antiparallel strands

A

One strand of DNA runs one way the other side runs the opposite direction. 5 prime and 3 prime ends

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

RNA structure

A
Ribonucleic acid
ribose sugar
Bases A,G,C,U
Single strand
Three types: mRNA, tRNA, rRNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

DNA replication

A

DNA is copied in binary fission to give two exact copies of chromosome to the dividing cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does semiconservative mean in terms of DNA replication

A
  • Only one strand is “conserved” from original

- One strand is the template and the other is the copy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

New DNA strand is only made from …

A

5’ to 3’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Nucleotides are only added to which end of the DNA strand

A

3’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Starting Replication envolves what two areas

A

Origin of replication

Replication fork

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Origin of replication

A

Specific DNA sequence that is recognized by enzymes as the starting point
-Unwinding of DNA (unzipping) starts here

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Replication fork

A

where unwinding occurs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Two different DNA stands

A

Leading strand and Lagging strand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Leading strand

A

the new DNA strand that is made continuously toward the replication fork 5’ to 3’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Lagging Strand

A

the new DNA strand that is made in pieces AWAY from the replication fork

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Leading Strand

process

A
  1. Helicase unzips DNA
  2. Gyrase relaxes twisting of unwinding strands
  3. Primase adds RNA primer at origin of replication
  4. DNA polymerase adds nucleotides to 3’ end of new DNA through complementary base pairing
  5. goes in direction of unwinding parent DNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Lagging Strand

process

A
  1. Primase starts near the replication fork
  2. DNA polymerase adds neucleotides in 5’ to 3’ direction AWAY from unwinding and replication fork
  3. DNA polymerase detaches and goes back to replication fork and a new primer to make a new Okazaki fragment
  4. RNA Primers are removed by DNA polymerase
  5. Fragments are joined by DNA ligase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Lagging strand is formed in pieces called…

A

Okazaki fragments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Prokaryote DNA replication vs Eukaryote

A

Prokaryote will only have one point of origin, where eukaryotes can have several replication bubbles to speed up the process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Protein Synthesis Overview

A

Transcription - DNA to mRNA

Translation - mRNA to protein using tRNA and ribosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Transcription Steps

protein synthesis

A

Initiation
Elongation
Termination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Initiation

Transcription-Protein

A
  1. Sigma factor on RNA polymerase recognizes promoter on DNA
  2. RNA polymerase binds to promoter
  3. RNA polymerase unwinds DNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Elongation

transcription - protein

A

RNA nucleotides matched to DNA nucleotides

A to U, T to A, G to C, C to G

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Termination

transcription - protein

A

Terminator on DNA tells RNA polymerase to detach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Translation

protein synthesis

A

mRNA to protein using tRNA and ribosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Codon

A

three mRNA nucleotides “translate to one amino acid”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Start codon

A

AUG - Methionine

protein synthesis will always start with this

27
Q

Stop codon

A

UAA, UAG, UGA

will stop synthesis

28
Q

tRNA

A
  1. Single strand of folded RNA
  2. Amino acid attached to one end
  3. Anticodon is on other end
29
Q

Anticodon

A

match up to amino acid on the other side (will be the opposite “code” of the amino acid)

30
Q

Location of Anticodon and codon

A

Anticodon is on tRNA

Codon is on mRNA

31
Q

Ribosomes are composed of

A

proteins and rRNA

32
Q

Prokaryote ribosomes

A

30S + 50S = 70S

33
Q

Eukaryote ribosomes

A

40S + 60S = 80S

34
Q

Small unit of ribosomes has ____ binding site(s) for ____

A

one binding site for mRNA

35
Q

large subunit for ribosomes has ____binding site(s) for ____

A

three binding sites for tRNA

36
Q

How does Erythromycin work

A

binds to the 50S subunit and inhibits protein synthesis

37
Q

Large subunit binding sites

A

A site = Amino Acid
P site = polypeptide
E site = exit
Sites are arranged in EPA

38
Q

Translation : 3 steps

A

Initiation
Elongation
Termination

39
Q

Initiation

Translation

A
  1. ribosome binds to mRNA at ribosome binding site
  2. tRNA will bind to starter codon at P site
  3. another tRNA will bond to the next codon at the A site and a polypeptide bond will connect the two amino acids
40
Q

Elongation

Translation

A
  1. Ribosome moves to next codon
  2. Ribosome keeps moving along mRNA in 5’ to 3’ direction and amino acids added one at a time to make a long polypeptide chain
41
Q

Termination

translation

A
  1. Stop codon on mRNA that is not recognized by any tRNA

2. components come apart and polypeptide chain is released

43
Q

Which type of cell can transcription and translation happen simultaniously

A

Prokaryotes

44
Q

Comparing Protein Synthesis

A
Eukaryote
1. mRNA has introns and special endings
2. Monocisronic
3. mRNA must be transcribed and moved from nucleus to cytoplasm before translation can start
PROKARYOTE
1. mRNA is not processed
2. Polycistronic
3. Transcription can work before translation is finished
45
Q

Monocistronic

A

information for only one gene is found on the mRNA

Eukarote

46
Q

Polycistronic

A

mRNA can carry information for more than one gene

Prokaryote

47
Q

Post-translation modification of proteins

A
  • polypeptide chain folded into inal functional structure with CHAPERONE proteins
  • SIGNAL SEQUENCES are added to polypeptides that will be transported to another area of the cell
48
Q

Bacteria gene regulation

A
  • Bacteria will take nurients from environment

- Bacteria can synthesize many nutrients

49
Q

Bacteria will take nutrients from environment….

A
  • turn off genes not needed
  • to save energy of biosynthesis
  • use energy for cell division
50
Q

Bacteria can synthesize many nutrients…

A
  • turn on genes needed

- slow down cell division

51
Q

Alternative sigma factors

A
  • alternative versions of sigma factors can be made to recognize different promoters
  • anti-sigma factors can be made by cell to inhibit sigma factors
52
Q

sigma factor

A

part of RNA polymerase that recognizes specific promoters

53
Q

Operon

A

a set of regularoty genes on DNA

54
Q

Operon’s function

A
  1. Genes for protein(s)
  2. Promoter
  3. Operator
  4. Activator- binging site
55
Q

Promoter

Operon

A

where RNA polymerase starts

56
Q

Operator

operon

A

sequence after promoter

57
Q

Activator- binding site

operon

A

sequence before promoter

58
Q

Repressors - Induction

A

Repressor protein released from the operator when inducer binds to repressor and transcription can start

59
Q

Stop =

repressors

A

Repressor + operator

60
Q

Go =

repressors

A

Repressor + inducer

61
Q

Repressors - Repression

A

Repressor protein must combine with corepressor to bind to operator and stop transcription

62
Q

Activators

A

Activator protein can bind to activator-binding site only when combined with an inducer
-then allows RNA polymerase to bind

63
Q

Stop

activators

A

Activator protein alone

64
Q

Go

activators

A

Activator protein + inducer

65
Q

Example

A

lac operon - codes for proeins involved in lactose degredation and transport in E.coli