DNA and Inheritance

Question 1

Allele

Answer 1

A different form of the same gene

Question 2

Dominant

Answer 2

A gene that controls a characteristic if it is present. It is given a capital letter.

Question 3

F1 Generation

Answer 3

The first generation after a genetic cross.

Question 4

F2 Generation

Answer 4

The second generation after a genetic cross.

Question 5

Genotype

Answer 5

The combination of genes an individual has for a particular charactersistic.

Question 6

Heterozygote

Answer 6

An individual who is heterozygous for that characteristic.

Question 7

Heterozygous

Answer 7

Both chromosomes in a pair containing different alleles.

Question 8

Homozygote

Answer 8

An individual who is homozygous for that characteristic.

Question 9

Homozygous

Answer 9

Both chromosomes in the pair containing the same alleles.

Question 10

Phenotype

Answer 10

How a gene expresses itself in an individual.

Question 11

Recessive

Answer 11

A gene that controls a characteristic if the dominant gene is not present. It is given a lower case letter.

Question 12

Selfing

Answer 12

The act of self-fertilisation in plants.

Question 13

Where is DNA found?

Answer 13

In the nucleus

Question 14

What does the DNA do?

Answer 14

The DNA forms a chemical ‘code’ which acts as instructions for the cell to make proteins.

Question 15

What are all enzymes?

Answer 15

Proteins

Question 16

What does the order of amino acids determine?

Answer 16

The structure and function of the protein formed

Question 17

What is DNA made up of?

Answer 17

2 long chains of alternating sugar and phosphate molecules connected by pairs of bases.

Question 18

What shape does DNA form?

Answer 18

A double helix.

Question 19

Which bases pair with each other?

Answer 19

Adenine and Thymine
Cytosine and Guanine

Question 20

What does the sequence of bases form?

Answer 20

The instructions in a form of code for the manufacture of proteins. It determines which amino acids are used and in what order.

Question 21

What is a sequence of 3 bases in a gene?

Answer 21

A triplet

Question 22

What does a triplet do?

Answer 22

Code for an amino acid which determines the structure and function of the protein formed.

Question 23

How does genetic profiling work?

Answer 23

1. Sample of cells collected
2. DNA extracted from cells
3. DNA sample cut into fragments using enzymes
4. Fragments separated into bands creating a genetic profile

Question 24

What can genetic profiling be used for?

Answer 24

Crime scenes
Comparing the DNA of species
Detecting genes in diseases

Question 25

What are the problems of genetic profiling?

Answer 25

Goes against human rights
You don’t know who can see you genetic profile

Question 26

What chromosomes do males have?

Answer 26

XY

Question 27

What chromosomes do females have?

Answer 27

XX

Question 28

What chromosomes do eggs contain?

Answer 28

X

Question 29

What does the baby’s gender depend on?

Answer 29

Which sperm cell fertilises the egg as sperm cells may contain an X or Y chromosome.

Question 30

What is used to illustrate sex determination?

Answer 30

A punnett square

Question 31

What is genetic engineering?

Answer 31

The modification of the genome of an organism by extracting genes and putting them into another and can also ‘swap’ one gene for another.

Question 32

What are the benefits of genetic engineering?

Answer 32

Crops can be designed to survive in difficult farming conditions
Increased crop yield
Used in medicine
Plants can be modified to produce oils or other substances that can be used as biofuels saving non-renewable resources.

Question 33

What are the risks of genetic engineering?

Answer 33

Long term effects of consumption of GM crops are unknown
Side effects
Pollen from GM crops can easily be carried out of the farm by wind or insects and could be introduced into the natural population.
Negative environmental impacts e.g. reduction in biodiversity and impact on food chains