Genetics Flashcards

1
Q

What is a nucleotide?

A

A monomer that joins together with other nucleotides to form DNA

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

What is a mutation?

A

A change in the order of bases on a strand of DNA which affect anything that the DNA section codes for

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

What is substitution?

A

When one base is changed for another

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

What is meiosis?

A

A type of cell division that results in four daughter cells each with half the number of chromosomes as the parent cell and is used to create gametes. For example, a sperm cell has half the number of chromosomes as a normal body cell. Meiosis produces haploid cells

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

What is the base pairing for DNA?

A

AT, CG

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

What is the base paring when producing a strand of mRNA?

A

AU, CG

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

What are the stages of meiosis?

A
  • Each chromosome is copied
  • The chromosomes move to the edges of the cell
  • The pairs of chromosomes divide into two separate cells
  • These cells divide again into two more cells with half the number of chromosomes, these cells or gametes only have one copy of each chromosome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is an allele?

A

A variant of a gene from your parents

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

What does heterozygous mean?

A

When chromosomes of the same pair have different alleles of the same gene

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

What does homozygous mean?

A

When chromosomes of the same pair have the same alleles of the same gene

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

What is a genotype?

A

Shows the alleles in an individual. For example Bb or bb

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

What is a phenotype?

A

The characteristics that are produced as a result of the alleles that the individual has

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

What is a zygote?

A

A fertilised egg

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

What is a recessive allele?

A

An allele that doesn’t show any impact unless paired with another of the same recessive allele. For example you two alleles that give you blue eyes for you to have blue eyes.

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

What is a dominant allele?

A

An allele that takes control/the one that is seen when the genotype is anything apart from two recessive alleles. It takes dominance over the recessive alleles

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

How do you work out the probability of having a particular genotype?

A

Using a Punnett square

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

What is co-dominance?

A

This is when there are two different dominant alleles and they both take dominance, creating a new genotype. This is most common in blood groups

18
Q

What is cystic fibrosis?

A

A genetic disease and mutation that cause a build up of mucus in many organs and other small passages

19
Q

What causes cystic fibrosis?

A

When both copies of the CFTR gene are faulty. If only one is faulty then they don’t have the disease but are a carrier

20
Q

What is genetic modification?

A

A process used to copy desired characteristics from one organism to another

21
Q

How does genetic modification work?

A

Certain enzymes can cut pieces of DNA with a desired characteristic from one organism, and join them into a gap in the DNA of another organism. This means that the new organism with the inserted genes has the genetic information for one or more new characteristics. For example, the organism might produce a useful substance, or be able to carry out a new function.

22
Q

What was Mendel’s experiment?

A
  • He created pure-bred peas to use in his experiment
  • He cross-bred pure-bred dwarf peas with pure-bred tall peas to make the first generation of peas in his experiment and discovered that all offspring were tall. The allele for tall peas was dominant and the allele for dwarf peas was recessive
  • Mendel then removed all the pure-bred peas and cross-bred the offspring with other offspring to make the second generation. Around 25% of the second generation were dwarf peas. This was because the first generation were carriers of the allele that makes dwarf peas
23
Q

What chromosomes does a male have?

A

X, Y

24
Q

What chromosomes does a female have?

A

X, X

25
Q

Which blood group is co-dominant?

A

AB - I^A I^B

26
Q

What causes variation?

A

Conditions that the person lives in, differences in allele, combination of both conditions and differences in allele

27
Q

What does a mutation do?

A

Affect the amount of protein produced and its shape and sometimes affect the phenotype of an organism

28
Q

What is the human genome project?

A

A collaboration between scientists to decode the human genome (all the genetic information in an organism)

29
Q

What are the advantages of the human genome project?

A
  • It made it possible to alert people if they’re at risk of a certain disease
  • Allows scientists to distinguish between different forms of the same disease
  • Allows doctors to tailor treatment for individuals as specific alleles affect how the person reacts to the treatment
30
Q

What is addition?

A

Where bases are added to a DNA sequence

31
Q

What is deletion?

A

Where bases are removed from a DNA sequence

32
Q

How do enzymes break down substrates?

A

The enzyme specific active site collides with the complementary substrate, activation energy starts the reaction in which the substrate gets broken down

33
Q

What is activation energy?

A

The energy required to start a reaction

34
Q

What does it mean when an enzyme is denatured?

A

When an enzymes active site changes shape so it’s not complementary to it’s substrate anymore. Enzymes are denatured due to an extreme temperature or pH

35
Q

What does amylase break down?

A

Starch into glucose

36
Q

What does lipase break down?

A

Lipids into fatty acids and glycerol

37
Q

What does protease break down?

A

Proteins into amino acids

38
Q

What do gametes fuse to make?

A

A diploid zygote

39
Q

How does transcription happen?

A
  • DNA unwinds
  • RNA polymerase binds to non-coding DNA in front of gene
  • Free complementary bases bind to open bases
  • RNA polymerase joins free nucleotides together to form a strand of mRNA
40
Q

How does translation happen?

A
  • RIbosome moves along mRNA strand reading one codon at a time
  • tRNA molecules bring amino acids to the ribosome
  • Complementary tRNA bases pair with the bases on the mRNA strand
  • Amino acids that are close together are joined together to form a polypeptide chain
  • tRNA is now free to collect another amino acid
41
Q

What stops translation?

A

A stop codon