Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology - AQA - Extras > AO1 - Unit 4 > Flashcards

AO1 - Unit 4 Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Give 3 features of the DNA of prokaryotic cells

A

Short, circular, not associated with proteins

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

Give 3 features of the DNA of eukaryotic cells

A

long, linear, associated with histone proteins

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

What is a chromosome?

A

DNA molecule and its associated proteins

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

Give 3 places in a eukaryotic cell where DNA is found

A

nucleus, mitochondria, chloroplast

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

What is a gene?

A

a DNA base sequence that codes for a polypeptide

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

Name 2 types of functional RNA

A

rRNA and tRNA

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

What is a locus?

A

the position occupied by the gene on the DNA molecule

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

How many DNA bases code for one amino acid?

A

3

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

Give 3 features of the genetic code

A

universal, non-overlapping and degenerate

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

What are exons?

A

coding parts of DNA

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

What are introns?

A

non-coding parts of DNA

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

What can be found between genes?

A

non-coding multiple repeats of base sequences

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

Define 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
14
Q

Define proteome

A

the full range of proteins that a cell is able to produce

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

What is transcription?

A

the production of mRNA from DNA

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

What is the role of RNA polymerase?

A

joins RNA nucleotides together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How does transcription differ in prokaryotes and eukaryotes?

A

In eukaryotes a pre-mRNA is made which has to be spliced/edited

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

What is translation?

A

the production of a polypepetide from the mRNA

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

Where does translation occur?

A

ribosomes

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

Name the 3 base code on mRNA

A

codon

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

Name the 3 base code on tRNA

A

anti-codon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Name the 4 bases in DNA?

A

adenine, thymine, cytosine and guanine

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

Name the 4 bases in RNA?

A

adenine, uracil, cytosine and guanine

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

Describe the structure of mRNA

A

a single long strand of RNA nucleotides- a copy of a gene

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

Describe the structure of tRNA

A

a small, clover shaped molecule

26
Q

What is the role of tRNA?

A

Brings amino acids to the ribosome during translation

27
Q

What does DNA helicase do?

A

Causes H bonds to break enabling DNA strands to separate

28
Q

Are both DNA polynucleotide strands copied?

A

No- just the sense strand

29
Q

What is role of ATP in protein synthesis?

A

provides energy for condensation reaction

30
Q

When does translation stop?

A

when a stop codon is reached

31
Q

What is the source of all variation?

A

mutation

32
Q

Give 3 types of gene mutation

A

Substitution, addition, deletion

33
Q

Give 3 consequences of gene mutation

A

lethal, no effect, beneficial

34
Q

When do gene mutations occur spontaneously?

A

During DNA replication

35
Q

What can increase the rate of mutation?

A

Mutagenic agents e.g. uv light

36
Q

Mutations in the number of chromosomes can occur spontaneously by what process?

A

Non- disjunction during meiosis

37
Q

How many daughter cells are produced during meiosis?

A

four

38
Q

How do the daughter cells compare to parent cell?

A

haploid, genetically different

39
Q

How many nuclear divisions during meiosis?

A

2

40
Q

Name 2 processes which bring about variation during meiosis?

A

crossing over, independent segregation

41
Q

How many different combinations of chromosomes are there following meiosis, without crossing over, if the cell has 23 pairs of chromosomes?

A

2 23

42
Q

How is variation increased during sexual reproduction?

A

random fusion of gametes

43
Q

Give 1 example of natural selection in action

A

antibiotic resistance in bacteria

44
Q

Describe the 4 key features in natural selection that enable natural selection to occur

A

random mutation can result in new alleles, some mutations may lead to selective advantage, advantageous allele passed on to next generation, new allele increases in frequency

45
Q

What is meant by directional selection?

A

a type of natural selection in which the selection pressure is shifted towards one end of the variation range by favouring more extreme phenotypes over others

46
Q

Give an example of directional selection.

A

antibiotic resistance in bacteria

47
Q

What is meant by stabilising selection?

A

A type of natural selection in which the selection pressure favours the mid range of a phenotype

48
Q

Give an example of stabilising selection.

A

Birth weight of human babies

49
Q

Natural selection results in species that are better adapted to the environment. What are the 3 types of adaptation?

A

Behavioural
Anatomical
Physiological

50
Q

Define species

A

A group of individuals with observable similarities and the ability to interbreed to produce fertile offspring

51
Q

Why is courtship behaviour important?

A

species recognition, synchronise breeding behaviour, find fit mates without aggression

52
Q

How does a phylogenetic classifications ystem attempt to arrange species into groups?

A

Based on evolutionary origins and relationships

53
Q

The system is hierarchical. What does this mean?

A

smaller groups are arranged into larger groups with no overlap

54
Q

List the names of the taxons from largest to smallest- starting with domain

A

domain, kingdom, phylum, class, order, family, genus, species

55
Q

Define biodiversity

A

In conservation, a measure of the number of different species in a particular ecosystem

56
Q

Define species richness

A

A measure of the number of different species in a community

57
Q

An index of diversity describes the relationship between what?

A

the number of species in a community and the number of individuals in each species

58
Q

The formula to calculate index of diversity is:

A

d = N(N-1)/Σn(n-1)

59
Q

Do farming practices increase or decrease biodiversity?

A

decrease

60
Q

Name 4 things you could compare to investigate genetic diversity.

A

observable characteristics, DNA base sequences, mRNA base sequences, Amino acid sequences

61
Q

What is standard deviation?

A

spread of data around a mean

Biology - AQA - Extras (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions