Genetics

Question 1

What is a Mutation?

Answer 1

A change in the DNA

Question 2

What is degenerate coding?

Answer 2

Can code for same amino acid even if a mutation occurs.

Question 3

define trait

Answer 3

Variant for a character (different versions of something)

Question 4

define phenotype

Answer 4

organisms traits
- this is the expressed gene

Question 5

define genotype

Answer 5

genetic makeup
- sets of genes you have

Question 6

Define homozygous?

Answer 6

homozygous is two of the same alleles
- homozygous recessive
- homozygous dominant

Question 7

define heterozygous

Answer 7

one type of the allele

Question 8

What did Gregor Mendel do?

Answer 8

Carried out experiments using pea plants to see how certain traits are inherited.

Question 9

What are Mendel’s laws?

Answer 9

Mendel’s laws include the Law of Dominance and Uniformity, the Law of Segregation, and the Law of Independent Assortment.

Question 10

What is the law of segregation?

Answer 10

Pairs segregate during the formation of gamete and re-unite randomly during fertilisation.

Question 11

What is the law of independent assortment?

Answer 11

the allele a gamete receives for one gene does not influence the allele received for another gene.

Question 12

What is the law of Dominance?

Answer 12

one allele masks another for a single gene, and heterozygotes express the dominant phenotype.

Question 13

What are all the sets of chromosomes called?

Answer 13

Karyotype

Question 14

What are homologous chromosomes?

Answer 14

Pairs of chromosomes having the same genes but different alleles.

Question 15

What is monogenic and polygenic?

Answer 15

monogenic - involves one gene
polygenic - involves more Than one gene (involves the environment)

Question 16

Give an example of a recessive disorder and explain what it is?

Answer 16

PKU - where an enzyme called phenylalanine becomes functionless and gets converted into an acid.

Question 17

Give an example of a dominant disorder

Answer 17

Huntington’s disease - symptoms start to show later in life.
- it affects the nervous system so you have uncontrolled movements.

Question 18

Give an example of a x linked recessive disorder

Answer 18

Haemophilia
- internal bleeding and retinal bleeding
- one copy of the altered gene on the X chromosome causes the disease in a male.

Question 19

What is an advantage of having sickle cells?

Answer 19

If a person has sickle cells, they won’t have the likelihood of developing malaria, as it needs healthy cells to complete its life cycle.