Variations in heredity (genetics)

Question 1

what are 3 of mendels laws? (name)

Answer 1

1. the Law of Dominance
2. the Law of Segregation
3. the Law of Independent Assortment

Question 2

what is the law of dominance?

Answer 2

In a cross of parents that are pure for contrasting traits, only one form of the trait will appear in the next generation (F1). (1 alelle dominates over the other)

Offspring that are hybrid for a trait will have only the dominant trait in the phenotype.

But the recessive trait will still be passed down

Question 3

the law of segregation?

Answer 3

offspring/organism inherit 2 copies of genes, one from each parent

parents can only give 1 copy of their genes to a gamate (sex cell)

Question 4

the law of indepedent assortment

Answer 4

-> all allelles of different traits are distruibted to sex cells and offspring independently

-> there is no links between allelles (the inheritence of one trait does not influence the other)
->ie inheriting blue eyes does not mean you will inherit the trait of being tall (no connection)
-> everything is randomized

Question 5

what is the spectrum of dominate and what are the 3 types of dominances

Answer 5

Alleles can show different degrees of dominance and recessiveness in relation to each other

complete dominance -> incomplete dominance -> co-dominance

Question 6

what is complete dominance?

Answer 6

1 allele is complete dominate over the other, and if present it will always be physically expressed

Question 7

what is incomplete dominance?

Answer 7

-> neither alleles dominate each other, therefore both express the indivdual and are partially expressed

-> a “mix happens”
–> ie: red + white = pink (red and white are alleles that are partially dominate

Question 8

codominance?

Answer 8

alleles are both dominate and if present will be expressed fully no matter what, causing a third phenotype

ie: black cow + white cow = spotted cow

Question 9

what are blood types (type of inhertiance)

what are the 4 blood types and their alleles?

Answer 9

blood types are an example of complete dominance and codominance

Type A (I^A I^A, I^A i)
Type B (I^B I^B, I^B i)
Type AB (I^A I^B)
Type O (ii)

Question 10

Who is the universal recipant of blood? Who is the universal donar?

Answer 10

Type AB can receive anytype of blood

Type O can give anytype of blood

Question 11

What is polygenic inheritance?

Answer 11

a trait can be influenced by two or more genes. ie skin colour is affected by more than 1 allele.

these genes have an additive manner, which means that each gene that affects this trait “adds on to” this trait