Nucleic Acids Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is a nucleotide?

A

molecule consisting of a 5-carbon sugar, phosphate group, nitrogenous base
are phosphate esters of pentose sugars

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

Nucleotides form the ________ of _______ _____

A
monomers
nucleic acids (DNA, RNA)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

the nucleotide pentose sugar of DNA is…

A

deoxyribose

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

the nucleotide pentose sugar of RNA is…

A

ribose

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

if nucleotides contain more than 1 _________ group, they become ______________ ___________

A
phosphate 
phosphorylated nucleotides (ADP, ATP)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

nucleotides can…

and can be…

A

regulate metabolic pathways

components of coenzymes

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

What is the bond between a 5-carbon sugar and a phosphate group?

A

phosphodiester

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

A
C
G
T

A

Adenine
Cytosine
Guanine
Thymine

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

2 ______________ strands of DNA run ____ ________ and are joined by ________ _____.

A

polynucleotide
anti parallel
hydrogen bonds

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

adenine and guanine are…

thymine and cytosine are…

A

purine nitrogenous bases (2 rings)

pyrimidine (1 ring)

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

A-T have…

G-C have…

A

2 hydrogen bonds

3 hydrogen bonds

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

the upright part of a large DNA molecule is…

A

the sugar-phosphate backbones of anti parallel polynucleotide strands

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

5’ is when…

3’ is when…

A

the phosphate group is attached to the 5th carbon of deoxyribose sugar
phosphate group is attached to the 3rd carbon

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

Semi-conservative replication is…

A

2 new molecules, each has one old and one new strand. The old strand is conserved.

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

DNA replication process:

A

1) DNA molecule unwinds and double helix untwists (gyrase enzyme)
2) unzips hydrogen bonds between nucleotide bases, so 2 single strands now (DNA helicase)
3) free phosphorylated nucleotides in nucleoplasm in nucleus bond to exposed bases. In 5’ to 3’, leading strand synthesised continuously, lagging strand in fragments (DNA polymerase). Lagging strand later joined (ligase enzyme)
4) phosphodiester bonds between sugar residue of 1 nucleotide and phosphate group of the next. The energy comes from, hydrolysis of activated nucleotides to release extra phosphate groups
5) 2 DNA molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Mutation is when…

A

an error occurs and the wrong nucleotide is inserted which changed the genetic code.

17
Q

Transcription

A

1) gene unwinds
2) H bonds between bases break
3) temporary H bonds between RNA nucleotides and unpaired DNA bases (template strand - DNA strand) (RNA polymerase)
4) length of RNA complementary to template strand produced - coding strand
5) mRNA out nucleus to ribosomes
6) DNA zips back up

18
Q

RNA is different from DNA because…

A

it is single stranded and a shorter chain

there are 3 forms of RNA, messenger, transfer, ribosomal

19
Q

Why is mRNA made?

A

instructions inside genes can’t pass out the nucleus so it is copied/transcribed into mRNA.

20
Q

Codons

A

sequence of base triplets

21
Q

tRNA has an…

A

anti-codon on one end and an amino acid on the other

the anti-codon is complementary to the codon on mRNA

22
Q

Translation

A

1) tRNA binds to mRNA triplet by temporary H bonds
2) ribosomes move along mRNA, reads code and amino acids join up by peptide bonds
3) mRNA breaks down, recycled and the polypeptide folds into 3D structure to carry out function.