Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology > Genetics > Flashcards

Genetics Flashcards

(58 cards)

Start Studying
1
Q

What does RNA do

A

Transfers genetic information from DNA to ribosomes

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

What are the components of DNA nucleotide

A

Deoxyribose, phosphate group, one base: adenine thymine cytosine and guanine

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

What are the components of RNA

A

Ribose, phosphate and one base- adenine uracil cytosine and guanine

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

How are both DNA and RNA nucleotides joined

A

By a condensation reaction forming phosphodiester bonds

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

What are DNA molecules like in prokaryotic cells

A

Short circular and not associated with proteins

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

What are DNA molecules like in eukaryotic cells

A

Long linear and associated with proteins called histones

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

What does a gene code for

A

Amino acid sequence of a polypeptide
A functional RNA

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

What is the fixed position of a gene called

A

Locus

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

What is the DNA of mitochondria and chloroplast much like

A

Prokaryotic DNA- short circular and not associated with proteins

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

What is a sequence of three bases called

A

Triplet

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

What does the genetic code being universal mean

A

Same triplets code for the same amino acids in all living things

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

What does the genetic code being non overlapping mean

A

Each base is a part of only one triplet

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

What does the genetic code being degenerate mean

A

Most amino acids have more than one triplet that codes for it

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

What are exons

A

Coding regions that code for a sequence of amino acids

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

What are non coding sequences called

A

Introns

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

What are a homologous pair of chromosomes

A

Two chromosomes that carry the same genes but different alleles

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

What are alleles

A

Different form of the same gene

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

What is the genome

A

Complete set of genes in a cell

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

What is the proteome

A

Full range of proteins that a cell is able to make

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

What is the structure of mRNA

A

Long single strand
Each set of three bases are called a codon, pairs with triplet on DNA
Involved in transcription

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

What is the structure of tRNA

A

Single strand folded into clover leaf shape held together via hydrogen bonds
One end extends which is called the amino acid binding site
Opposite end there is an anticodon which is complementary to codon on mRNA

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

Process of transcription

A

DNA unzips, breaking hydrogen bonds between complementary base pairs
One of the DNA strands acts as a template
Free RNA nucleotides align by complementary base pairs (a+u)(c+g)
RNA polymerase joins RNA nucleotides together via a condensation reaction forming phosphodiester bonds
RNA detaches once it reaches a stop codon
Pre mRNA is spliced

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

What is splicing

A

Introns are removed out of pre mRNA to just leave exons

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

In what cells does transcription result directly in production of mRNA from DNA

25
In what cells does transcription result in production of pre mRNA
Eukaryotic
26
What is the process of translation
mRNA moves out of nucleus via nuclear pores and attaches to ribosome tRNA molecules carry amino acids to mRNA tRNA anticodon bind to first codon on mRNA by complementary base pairing Second tRNA molecule attaches itself to next codon on mRNA Condensation reaction between amino acids forming peptide bonds with use of ATP Ribosome moves along realising first tRNA allowing for a third to bind, repeats until ribosome reaches a stop codon Polypeptide is released
27
Describe the role of ATP in translation
ATP releases energy And energy is needed to join amino acids together to form peptide bonds and to join amino acid to tRNA for it to be carried
28
29
What is a gene mutation
Involves a change in base sequence of chromosomes
30
When do mutations arise spontaneously
During DNA replication
31
Why can mutations cause no effect
Genetic code is degenerate therefore amino acid sequence may not change
32
What are the two types of mutations
Substitution and deletion
33
What is substitution mutation
One nucleotide is replaced by another
34
What is deletion mutation and what does this result in
Nucleotide is lost which leads to frame shift resulting in a completely different amino acid being coded for
35
What does non disjunction mean
Chromosomes fail to separate correctly and as a result zygotes formed will have one more or one less chromosome
36
What does mutagenic agent mean
Factor that increases rate of mutations
37
What is meiosis
Cell division that gives 4 daughter cells that are all genetically different
38
How is genetic variation achieved
Independent assortment of chromosomes Crossing over of chromatids
39
How does independent assortment of chromosomes lead to genetic variation
During meiosis 1 homologous chromosomes line up in pairs, arrangement is random so division into daughter cells is also random
40
How does crossing over of chromatids lead to genetic variation
When pairs of chromosomes line up they exchange genetic information, crossing over occurs when one chromatid recombines with another chromatid leading to different combination of alleles on the gene
41
What occurs in meiosis 1
Homologous chromosomes separate to produce two daughter cells
42
What occurs in meiosis 2
Two daughter cells divide again into four haploid cells Chromosomes divide into chromatids
43
How is mitosis and meiosis different
Mitosis- one division and produces two genetically identical daughter cells Meiosis- two divisons and produces four genetically different daughter cells
44
How many chromosomes is haploid
23
45
How many chromosomes is diploid
46
46
What is genetic diversity
Number of different alleles of genes in a population
47
What does genetic diversity enable
Natural selection
48
What is natural selection
Fitter individuals who are better dated to the environment are more likely to survive and reproduce to pass on advantageous genes
49
What is evolution
Frequency of alleles in a gene pool changes over time as a result of natural selection
50
Process of natural selection via evolution
Random mutation results in new alleles New allele might benefit possessor, leading to individual being more likely to survive and reproduce Advantageous allele id inherited by members of the next generation As a result over generations new allele increases in frequency in the population leading to evolution
51
What are the two types of natural selection
Directional and stabilising
52
What is directional selection
Occurs when environment changes and phenotypes best suited are more likely to survive and reproduce and overtime the mean population will move in direction of these individuals
53
Example of directional selection
Bacteria being resistant- single bacteria has a mutation then frequency of allele increased in population then population moved to have greater antibiotic resistance
54
What is stabilising selection
Occurs when there is no change in environment, phenotypes that have selective advantage are preserved, trait stays the same and those with extreme phenotypes are selected against
55
Example of stabilising selection
Baby birth weights- birth weight of 3kg more likely to survive than those at extreme weights
56
What are anatomical adaptations
Physical
57
What are behavioural adaptations
Behaviour- how organism acts
58
What are physiological adaptations
Processes inside an organisms body

Biology (4 decks)

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