1 - Genetics

Question 1

Define Variation

Answer 1

The presence of differences between living things of the same species.

Question 2

Allele

Answer 2

A different version / form of the same gene.

Question 3

Gene

Answer 3

A section of DNA that determines (e.g.) a certain characteristic, such as your hair colour, eye colour etc.

Question 4

Dominant Allele

Answer 4

When an allele is always expressed, even if there is only one of them.

Question 5

Recessive Allele

Answer 5

An allele that will only be expressed if inherited from both parents.

Question 6

Phenotype

Answer 6

The physical characteristic of a specific species.

Example: Red Petals or Yellow Petals

Question 7

Genotype

Answer 7

The allele pair for each characteristic.

Question 8

Homozygous

Answer 8

When the alleles in a matching pair are the same.

“Homo” = Same

Question 9

Heterozygous

Answer 9

When the alleles in a matching pair are different.

“Hetero” = Different

Question 10

Punnett Square

Answer 10

Shows the possible combinations of alleles inherited from parents.

Question 11

What sex chromosomes are associated to a Male and a Female?

Answer 11

XX / (46XX)= Female

XY / (46XY)= Male

Question 12

What are the mains involved in Selective Breeding?

Part A

Answer 12

1) Choose parents with desirable characteristics, which are important enough to select.
2) Allow them to breed together.

Question 13

What are the main steps involved in Selective Breeding?

Part B

Answer 13

3) Choose the best offspring which also show the desirable characteristics.
4) Breed them again, which is then repeated over many generations.

Question 14

What are some Ethical concerns to Selective Breeding?

Answer 14

• Increase in inherited disorders.

- Violates animal’s rights in a way, where they are treated as human property.

Question 15

What are some Welfare concerns to Selective Breeding?

Answer 15

• More susceptible to diseases.
• Can cause unnatural birth in some cases!
• Mortality rate can increase in the species, being affected by conditions such as Arthritis.
• Reduces the gene pool, therefore reducing variation in the species.

Question 16

What is Cloning?

Answer 16

Where an identical genetic copy of the parent plant / animal is created.

Question 17

What is Asexual Reproduction?

Answer 17

When there is only one parent needed (without any gametes) to produce offspring.

As a result, there is no mixing of genetic material, so the offsprings are clones.

Question 18

What are some Examples of Asexual Reproduction?

Answer 18

• Potato Plants
• Strawberry Plants
• Daffodils

Question 19

What are the steps involved in cloning a plant from a Plant Tissue Culture?

Answer 19

1) Tissue sample scraped from parent plant.
2) Sample is places in an agar growth medium, containing Nutrients and hormones.
3) Sample develops into tiny plantlets.
4) Plantlets placed into compost, growing to their full size and repeating the cycle.

Question 20

What are the main steps involved in Cloning Animals?

Part A

Answer 20

1) Any body cell taken from Sheep A.
2) Egg cell taken from Sheep B.
3) Nucleus from Sheep B is isolated and inserted into isolated egg cell of Sheep A.

Question 21

What are the main steps involved in Cloning Animals?

Answer 21

4) Newly-formed embryo is administered an electrical shock to encourage it to divide.
5) Embryo is implanted into a surrogate mother sheep / Sheep C.
6) Embryo grows into a lamb “clone” of Sheep A.

Question 22

Characteristics

Answer 22

The features of an organism.

Question 23

Gene Pool

Answer 23

The variety of genes available in a population.

Question 24

Who was Dolly the Sheep?

Answer 24

An example of cloning, being the first mammal to be cloned from an adult cell.

Question 25

Sexual Reproduction

Answer 25

Reproduction that involves gametes and two parents.

Question 26

What is a Clone?

Answer 26

A genetically identical organism.

Question 27

What are Gametes?

Answer 27

Gametes are sex cells, where the eggs are female gametes and sperm are male gametes.

Question 28

What are the Steps involved in Genetic Engineering - Human Insulin?

Answer 28

1) The insulin gene is taken from Human DNA from a Human Cell with enzymes.
2) A section of plasmid within a bacterium is cut away using Restriction Enzymes.
3) Human gene of the Human Insulin is inserted into the plasmid. This GM Bacterium will now produce Human Insulin!

Question 29

What is Genetic Engineering?

Answer 29

The transfer of DNA from one organism to another. For example, Bacterial cells can be GM’d so that they have the gene for producing human insulin.