Genotype, Phenotype Amd Inheritance

Question 1

What is a genotype?

Answer 1

The set of alleles that determines a characteristic. It is the genetic makeup

Question 2

What is a phenotype?

Answer 2

The observable characteristics

Question 3

What is genetics the study of?

Answer 3

Inheritance and variation

Question 4

What is a gene?

Answer 4

A section of DNA on a chromosome that codes for the production of a protein that controls a particular characteristic

Question 5

What is an allele?

Answer 5

Alternative form of a gene

Question 6

What does homozygous mean?

Answer 6

2 allele of a gene are the same

Question 7

What does hemizygous mean?

Answer 7

Only one allele of a gene of the X chromosome

Question 8

What is a dominant allele?

Answer 8

The allele in a heterozygote that determines the phenotype

Question 9

What is consanguinity?

Answer 9

A relationship between individuals that share a common ancestor

Question 10

What s the genetic implication of consanguinity

Answer 10

Offspring are more likely to inherit recessive disorder

Question 11

What type of inheritance is blood type?

Answer 11

Co-dominance

Question 12

How is your blood group determined?

Answer 12

Human isoglutamin gene codes for glycoproteins on the surface of red blood cells

Question 13

What is an autosomal chromosome?

Answer 13

One that is not an allosome (sex chromosome)

Question 14

For an autosomal recessive disease what is the probability that 2 heterozygous parents will have an affected offspring?

Answer 14

25%

Question 15

Can autosomal recessive diseases skip generations?

Answer 15

Yes

Question 16

Why are autosomal dominant diseases rarely found in homozygous state?

Answer 16

Having 2 dominant alleles is usually not viable for life.

Question 17

What individuals are affected by X linked recessive diseases?

Answer 17

Hemizygous males and homozygous females

Question 18

Why are x linked recessive diseases more likely in females than males

Answer 18

Females need both copies to be affected whereas males only need one

Question 19

What type of diseases is Haemophilia A an example of?

Answer 19

X linked recessive

Question 20

Are males and females equally affected from X linked recessive diseases

Answer 20

No

Question 21

From whom do you inherit your mitochondria from?

Answer 21

Your mum

Question 22

What does polygenic mean?

Answer 22

when more than one gene is involved in producing a phenotype

Question 23

Give an example of a disease with a polygenic inheritance

Answer 23

Albinism

Question 24

What are linked genes?

Answer 24

Gene that are found on the same chromosome

Question 25

What is the recombination frequency?

Answer 25

The chance of crossing over occurring between linked genes in a chromosome

Question 26

What is the recombination frequency dependant on?

Answer 26

The distance between the genes. If gene sare further apart there’s more opportunities for chiasmata to form

Question 27

What 3 things can you calculate/determine from pedigree diagrams

Answer 27

Recombination frequency, probability of inheritance and inheritance pattern