10.4 Genotypes and phenotypes

Question 1

What is a genotype? Give an example:

Answer 1

-The genes an individual contains
-Can be homozygous and heterozygous
Eg. Ee

Question 2

What is a phenotype? Give an example:

Answer 2

-The physical appearance of an individual
-Are influenced by the genotype and the environment
Eg. Brown eyes

Question 3

What does the term homozygous mean? Give an example:

Answer 3

When to alleles are the same.

Eg. RR, rr

Question 4

What does the term heterozygous mean? Give an example:

Answer 4

When the two alleles are different.

Eg. Rr

Question 5

Give an example of genes that have more than two alleles:

Answer 5

Blood groups, which are determined by a combination of the three different alleles.

Question 6

What is co-dominance?

Answer 6

Where both traits are shown in a heterozygote.

Eg. AB

Question 7

What does polygenic mean?

Answer 7

Where many genes and alleles contribute.

Eg. Height in humans, hair colour shade

Question 8

Give examples of how phenotypes can be influenced by the environment:

Answer 8

• Diet
• Temperature
• pH

Question 9

What can phenotypes be influenced by?

Answer 9

• Diet
• Temperature
• pH
• Epigenetic effects (Non-genetically influenced)

Question 10

What is the purpose of epigenetics?

Answer 10

To modify DNA by adding or removing certain chemical modifications, while the DNA sequence is not changed.