Genotype, Phenotype Amd Inheritance Flashcards Preview

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Flashcards in Genotype, Phenotype Amd Inheritance Deck (27)
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1

What is a genotype?

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

2

What is a phenotype?

The observable characteristics

3

What is genetics the study of?

Inheritance and variation

4

What is a gene?

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

5

What is an allele?

Alternative form of a gene

6

What does homozygous mean?

2 allele of a gene are the same

7

What does hemizygous mean?

Only one allele of a gene of the X chromosome

8

What is a dominant allele?

The allele in a heterozygote that determines the phenotype

9

What is consanguinity?

A relationship between individuals that share a common ancestor

10

What s the genetic implication of consanguinity

Offspring are more likely to inherit recessive disorder

11

What type of inheritance is blood type?

Co-dominance

12

How is your blood group determined?

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

13

What is an autosomal chromosome?

One that is not an allosome (sex chromosome)

14

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

25%

15

Can autosomal recessive diseases skip generations?

Yes

16

Why are autosomal dominant diseases rarely found in homozygous state?

Having 2 dominant alleles is usually not viable for life.

17

What individuals are affected by X linked recessive diseases?

Hemizygous males and homozygous females

18

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

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

19

What type of diseases is Haemophilia A an example of?

X linked recessive

20

Are males and females equally affected from X linked recessive diseases

No

21

From whom do you inherit your mitochondria from?

Your mum

22

What does polygenic mean?

when more than one gene is involved in producing a phenotype

23

Give an example of a disease with a polygenic inheritance

Albinism

24

What are linked genes?

Gene that are found on the same chromosome

25

What is the recombination frequency?

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

26

What is the recombination frequency dependant on?

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

27

What 3 things can you calculate/determine from pedigree diagrams

Recombination frequency, probability of inheritance and inheritance pattern