genetic inheritance

Question 1

what is the genotype for blood group A?

Answer 1

IA IA or IA IO

Question 2

what is the genotype for blood group B?

Answer 2

IB IB or IB IO

Question 3

what is the genotype for blood group AB?

Answer 3

IA IB

Question 4

what is the genotype for blood group O?

Answer 4

IO IO

Question 5

who do you inherit the x and y chromosomes from?

Answer 5

if boy:
x from mom, y from dad
if girl:
x from mom, x from dad

Question 6

why are men at more risk of sex-linked disorders? (3)

Answer 6

-Y chromosome is smaller than the X chromosome and does not have as many genes.
-If a gene is contained on the part of the X chromosome that is missing from the Y chromosome, men only have one allele for that gene
-If the allele on the X chromosome codes for a disorder, the man will always have the disorder because there isn’t another allele on the Y chromosome to mask the effect of the allele.

Question 7

what is used to encourage new roots to grow?

Answer 7

plant hormones

Question 8

describe the process of ‘cuttings’: (3)

Answer 8

-branch from the parent plant is cut off,
-its lower leaves are removed,
-the stem is planted in damp compost.

Question 9

describe the process of ‘tissue culture’: (5)

Answer 9

-tissue samples are scraped from parent plant
-tissue samples are sterilised
-then placed in an agar growth medium
-samples develop in tiny plantlets
-plantlets are planted into compost

Question 10

Embryo transplants: (5)

Answer 10

-sperm is taken from a bull from a high yield dairy herd
-cow is artificially inseminated with the sperm
-zygotes develop into embryos in the cow which are removed from the uterus
-embryos are split into several smaller cells before they become specialised (each of which can grow into a new calf)
-identical embryos are transplanted into host mothers

Question 11

Adult cell cloning: (5)

Answer 11

-the nucleus is removed from an unfertilised egg cell
-the nucleus from an adult body cell, such as a skin cell, is inserted into the egg cell
-an electric shock stimulates the egg cell to divide to form an embryo
-these embryo cells contain the same genetic information as the adult skin cell
-when the embryo has developed into a ball of cells, it is inserted into the womb of an adult female to continue its development

Question 12

why is biological control used?

Answer 12

releasing a natural predator into the crop growing area, the number of pests can be reduced