Brainscape's Knowledge GenomeTM

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


See full index

Biology > Genetics > Flashcards

Genetics Flashcards

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

Meiosis def

A

Production of four genetically different haploid (23 chromosomes) daughter cell gametes.
Happens in the ovaries and the testicles.

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

Zygote

A

Formed when speed and egg fuse their DNA together

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

DNA

A

A polymer inside the nucleus of cells, carrying the genetic information of a living being

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

Structure of DNA

A

A polymer. Two stands coiled together in a double helix. Strands linked by complementary base pairs (AT and CG / adenine + thymine and cytosine + guanine) held together by weak hydrogen bonds. Nucleotides consisting of sugar phosphate backbones and one of the four bases

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

Chromosome

A

Tightly wound up DNA and codes for all characteristics in an organism

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

Gene

A

A section of DNA that codes for a specific protein

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

Genome

A

The entire genetic information of an organism

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

DNA extraction

A

Mash it up. Add detergent (breaks down cell membrane) and salt (makes the DNA come out). Put it in hot bath 60° to denature the enzymes. Add enzyme solution. Add ice-cold ethanol to make the DNA insoluble so it can be extracted

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

Alleles

A

Different forms of the same gene

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

Human Genome Project aims

A

Early treatment. Less fatalities. Identifies which medicines are more successful. Identifies disease causing genes. Works out the order of 3 billion base pairs. Identifies all genes to develop faster methods for sequencing DNA.

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

Human Genome Project benefits

A

Improved genetic testing, can work out the chances of a person developing a genetic disease, created new gene therapy treatments, makes personalised medicines for a patients (identifies what works best to treat their illness as the alleles they have can affect how the medicines work)

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

Genotype

A

The alleles that make up a given feature

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

Phenotype

A

The characteristics we see

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

Examples of mono hybrid inheritance charts

A

Family pedigrees, Punnett squares, genetic diagrams

They show the probability of génotypes and phénotypes being passed on from one generation to the next

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

Mutation def

A

A change in the sequence of bases in the genetic code

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

Effects of genetic mutations

A

No effect, small effect, significant effect (rare)

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

How are mutations caused

A

A base/sequence incorrectly copied in cell division causes amino acids to be in the wrong order, resulting in different shapes of protein

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

Normal distribution curve

A

Continuous data of variation. Extremes. Average is the mode

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

Protein synthesis

A

The process of making proteins (chains of amino acids) like a natural polymer

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

Protein shape order

A

Order of bases in a section of DNA decides the order of amino acids in the protein. These fold into specific shapes which are unique to each type of protein e.g. enzymes. The protein determines how all the cells in the body function.

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

Transcription def

A

The first step of gene expression - a particular segment of DNA that is copied into RNA by the enzyme RNA polymerase

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

How many bases code for one amino acids?

A

Three bases aka triplet

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

Where are proteins means?

A

Cell cytoplasm to the ribosomes

24
Q

Transcription process

A

Takes place in the nucleus because DNA is too big to move out. The gene coding for the protein required untwists then unzips by the enzyme helicase to form a single helix structure. The hydrogen bonds between the strands break. One strand is the coding strand (template) then free RNA nucleotides form complementary base pairs to it using RNA polymerase in front of the gene. The enzyme binds to the non-coding strand and moves down it to bind the nucleotides. There is no thymine but uracil instead (bonds with adenine). Weak hydrogen bonds form between the base pairs. Sugar phosphate bonds form between RNA nucleotides. mRNA peels off the DNA and moves out of the nucleus into the cytoplasm. The coding DNA strand zips back to the non-coding strand after mRNA leaves through a nuclear pore. RNA never joins with DNA

25
Q

RNA polymerase

A

Enzyme that joins the RNA nucleotides to make RNA

26
Q

Translation def

A

The process in which cellular ribosomes create proteins - mRNA is decoded by a ribosome to produce a specific amino acid chain or polypeptide

27
Q

Ribosomes

A

The sites of protein synthesis

28
Q

mRNA

A

Messenger ribonucleic acid
- carries information from DNA to the ribosome. The coding sequence determines the amino acid sequence in the protein produced

29
Q

tRNA

A

Transfer ribonucleic acid

- reads mRNA, matches up and makes amino acids

30
Q

Translation process

A

It takes place in the cytoplasm on ribosomes. The mRNA attaches to a ribosome. This reads the mRNA. It decodes it into codons (reads it one triplet at a time as it goes along the ribosome) and the anticodons on tRNA are complementary to these bases and codes for one specific amino acid. The amino acids join together by peptide bonds to make a polypeptide chain (protein). tRNA is reused and collects another specific amino acid - once the protein is synthesised, mRNA may move to another ribosome to make another protein or it can be broken down into free nucleotides to be reused.

31
Q

Anticodon

A

3 bases on tRNA. They are complementary to the codons on mRNA. They code for one amino acid

32
Q

Polypeptide

A

Chain of amino acids held by peptide bonds

33
Q

Protein

A

Polypeptide chains made of amino acids and bonded together by peptide bonds

34
Q

Advantages and disadvantages of asexual reproduction

A

Pos - no need for a mate, rapid reproductive cycle

Neg - no genetic variation in population, disease is easily spread

35
Q

Advantages and disadvantages of sexual reproduction

A

Pos - genetic variation in the population

Neg - needs to find a mate

36
Q

How can genetic variants in the non-coding DNA affect phenotype?

A

It influences the binding of RNA polymerase. This alters the quantity of protein produced

37
Q

How can genetic variants in the coding DNA affect phenotype?

A

The sequence of amino acids is altered and therefore the activity of the protein produced is also altered

38
Q

Mendel - what he did and how

A

Scientist who discovered the basis of genetics by doing genetic experiments with pea plants. He cross fertilised the plants by opening an immature flower, cutting off the stamens before they dropped pollen. After it matured, he dusted the pistol with pollen from another plant. He noted how characteristics were passed on from one generation to the next.

39
Q

Why did Mendel use pea plants

A

Easy to grow and had many variable traits that he could observe. Plus, they can be crossed with themselves or other pea plants.

40
Q

Mendel discoveries

A

Each trait has two alternate forms e.g. seed colour either green or yellow or plant height tall or short. Each alternative form of a trait is specified by alternative forms of a gene. Pure bred plants have two copies of the same gene for each trait. He discovered that the genes didn’t blend e.g. white flower and red didn’t make pink. A tall plant and a small plant made all tall, but then two of these tall (hybrids) still made some small which is the recessive

41
Q

What were Mendel’s three important conclusions?

A
  1. Characteristics in plants are determined by hereditary units (now known as genes).
  2. These are passed on from both parents, one from each.
  3. These can be either dominant or recessive - if the individual has both the dominant and recessive gene then the dominant one will be expressed.
    This explained why we are all unique and understand how inheritance works
42
Q

How is sex of offspring determined?

A

At fertilisation. The woman (egg cell) has XX chromosomes and the man (sex cell) as XY chromosomes as the 23rd pair. This determines the sex. There is a 50:50 chance of either gender. The Y chromosome makes an embryo that develops a protein that causes testes to be made for a male. The X chromosome doesn’t produce this protein so ovaries are made instead for a woman

43
Q

Monohybrid cross

A

When two parent genotyoes are crossed to produce one phenotype

44
Q

Codominance

A

Equal levels of dominance - neither allele is recessive nor dominant over the other e.g. AB blood type

45
Q

Blood group A

A

IA IA, IA IO

46
Q

Blood group AB

A

IA IB

47
Q

Blood group B

A

IB IB, IB IO

48
Q

Blood group O

A

IO IO

49
Q

Carrier

A

Individual that has one faulty allele and one normal allele

50
Q

Cystic fibrosis alleles

A

Normal allele is dominant F and cystic fibrosis is caused by the recessive allele f. They would have a homozygous recessive ff gene and both parents would be carriers or sufferers

51
Q

Sufferer

A

Has both alleles expressing the disease

52
Q

Sex linked disorders e.g. Colour blindness

A

Woman doesn’t have it as the normal colour vision allele is dominant over the recessive colourblindness allele

53
Q

Sex linked disorders e.g. Norrie disease

A

Common more in men. Y chromosome is missing some genes to shield it from the dominant Norrie disease sections of the gene on the X chromosome

54
Q

Sex linked disorders

A

Y chromosome is missing some genes found on the X. Men have one less allele for some genes. If one of these X genes courses a genetic disorder, then they will develop that disorder. The woman could have a healthy dominant allele on the X to prevent her from getting the disorder. The probability is lower

55
Q

Sex linked disorders e.g. Haemophilia

A

The normal allele is dominant. Affected is recessive. More common in men. Women carriers don’t suffer as they have both affected and normal

56
Q

Marker molecules

A

Each blood type has a particular marker molecule on the RBC

A is A, B is B, AB is A and B, O is O

Biology (9 decks)

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