NESA Biology Genetic Variation
5 sample questions with marking guides and sample answers · Avg. score: 64.2%
Sheep have 54 chromosomes, while goats have 60 chromosomes. The hybrid offspring of a sheep-goat pairing is called a geep.
During fertilisation, an egg from the sheep is fertilised by a sperm from the goat, resulting in a geep.
Which of the following will be correct for the geep?
chromosomes
chromosomes
chromosomes
chromosomes
When a red camellia flower is crossed with a white camellia flower, all the offspring are covered in both red and white petals.
What is the reason for this occurrence?
One gene is controlling multiple characteristics.
Environmental factors affect the phenotype of camellia flowers.
Alleles for both red and white colour in camellia flowers are recessive.
Petal colour in camellia flowers is controlled by a co-dominance pattern of inheritance.
In rabbits, black fur is dominant to white fur. A male that is heterozygous for black fur is crossed with a female with white fur, producing 12 offspring.
Predict the number of offspring with white fur. Justify your response using a Punnett square.
Describe what is meant by the genotype of an organism.
Inherited mutations can affect the genotype of offspring. Describe how this occurs.
In blood group inheritance in humans, three alleles (i, and ) determine blood type, which can be type O, A, B or AB.
It is known that:
- allele produces type A and is co-dominant with allele , which produces type B
- allele i produces type O
- alleles and are dominant over allele i.
A father who is heterozygous type A and a mother who is heterozygous type B have children. Predict the likely frequency of phenotypes for their offspring. Show your working.