Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

biology > paper 1: DNA, Genes and Chromosomes, Proteinsynthesis > Flashcards

paper 1: DNA, Genes and Chromosomes, Proteinsynthesis Flashcards

1
Q

draw and label a diagram of a DNA nucleotide

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

what does DNA stand for

A

deoxyribonucleic acid

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

describe how a strand of DNA forms

A
  • many DNA nucleotides join together to make a DNA polynucleotide
  • these are joined between the sugar moecule of one nucleotide and the phosphate of another nucleotide with a phosphodiester bond via a condensation reaction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

describe how a DNA double helix forms

A
  • bases from 2 strands form complementary base pairs joined together with hydrogen bonds
  • the 2 strands twist and form a double helix
  • the strands are anti-parallel
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

why can you describe DNA strands as being anti-parallel

A

DNA base sequence is read one way on one strand and the opposite way on the other strand

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

fill in this table

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

define a gene

A

DNA base sequence which codes for the amino acid sequence of a polypeptide

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

define a gene locus

A

fixed position on a particular DNA molecule/ chromsome which a gene occupies

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

define a genome

A

the complete set of genes in a cell

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

define a proteome

A

full range of proteins a cell is capable to produce

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

the genetic code is univeral. what does this mean

A

the same triplets code for the same amino acids in all living organsims

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

genetic code is non-overlapping. what does this mean

A

the DNA triplets do not share bases

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

genetcic code is degenerate. what does this mean

A

more than 1 triplet can code for the same amino acid

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

why might there be more codes than there are amino acids

A
  • if there is a mutation in DNA then the amino acid sequence will be less likely to change so you still get a functional protein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how can a mutation in the DNA lead to a non-functioning protein or enzyme

A
  • if there is a mutation in the DNA, this can change the primary structure of the protein
  • can change the position of the hydrogen, ionic and disulfide bonds in the protien
  • whihc changes the tertiary structure of the protein
  • can lead to a non-functioning protein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

define an exon

A

DNA base sequences within genes that code for an amino acid sequence

17
Q

what are non-coding multiple repeats

A

DNA base sequences which do not code for an amino acid sequence

18
Q

what are introns

A

DNA base sequence within genes which dont code for an amino acid sequence

19
Q

describe the stages of transcription in a eukaryotic cell

A
  • the DNA strands separate by breaking the hydorgen bonds between complementary base pairs
  • only one strand acts as a template strand
  • RNA nucleotides are attracted to the exposed bases and bind by complementary base pairing (A to T, T to A, C to G, G to C)
  • the enzyme RNA polymerase joins the RNA nucleotides together by forming phosphodiester bonds
  • this forms pre-mRNA
  • introns are removed by splicing to form mRNA
20
Q

how does transcription differ in prokaryotes compared to eukaryotes

A

prokaryotes have no introns so splicing does not take place and mRNA is directly formed

21
Q

describe the stages of translation

A
  • a ribosome attaches to the mRNA molecule and moves to find the start codon
  • 2 codons fit into the ribosome at any one time
  • the tRNA molecules carry specific amino acids to the pribosome and the anticodon binds to the codon by complementary base pairing
  • the 2 amino acids form a peptide bond in a condensation reaction using energy from the hydrolysis of ATP
  • the first tRNA is released to pick up another amino acid
  • the ribosome moves along to the next codon
  • when the stop codon is reahed translation stops
  • polypeptide is released and ribosome detaches
22
Q

what is the role of mRNA

A

carries template of DNA code for onne gene to the ribosome for proteinsynthesis

23
Q

what is the role of tRNA

A

carries specific amino acids to the ribosome during proteinsynthesis

24
Q

where is mRNA found

A

nucleus/ cytoplasm

25
Q

where is tRNA found

26
Q

how many polynucleotide strands is mRNA made of

A

single stranded

27
Q

how many polynucleotide strands is tRNA made from

A

single stranded

28
Q

describe the shape of an mRNA molecule

29
Q

describe the shape of a tRNA molecule

A

folded into clover leaf shape held together by hydrogen bonds

30
Q

does mRNA contain hydrogen bonds

31
Q

does tRNA contain hydrogen bonds

32
Q

does mRNA have an amino acid binding site

33
Q

does tRNA have an amino acid binding site

34
Q

describe the size of an mRNA molecule

A
  • can be different lengths
  • longer than tRNA as has more nucleotides
35
Q

describe the size of a tRNA molecule

A

shorter and all the same length

36
Q

what are 3 bases in a strand of mRNA called

37
Q

what are 3 bases in a strand of tRNA called

biology (30 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions