WorksheetsIGCSE Biology Inheritance
Total questions: 16
Worksheet time: 8mins
What term is used to describe a version of a gene?
allele
genotype
phenotype
heterozygous
What term is used to describe an organism that carries two identical alleles for a gene?
dominant
recessive
homozygous
heterozygous
What term is used to describe an organism that carries two different alleles for a gene?
dominant
recessive
homozygous
heterozygous
What term is used to describe the observable features of an organism due to its genotype?
inheritance
phenotype
dominant
allele
Gary and Fiona are both healthy but produce a child with a genetic disease caused by a recessive allele.
Which of the following must be true?
The child could be heterozygous
Gary is homozygous and Fiona is heterozygous
Gary and Fiona are both homozygous
Gary and Fiona are both heterozygous
A plant has two different alleles of a gene, G, resulting in it having a green seed.
Which row of the table describes the phenotype and genotype of the seeds of this plant?
A
B
C
D
A person has the genotype Aa.
What is the correct description of this genotype?
heterozygous, with two different alleles of the same gene
heterozygous, with two different genes of the same allele
homozygous, with two different alleles of the same gene
homozygous, with two different genes of the same allele
The pedigree chart shows the inheritance of a genetic disorder in a family.
What conclusion can be made about this genetic disease?
The genetic disorder is dwarfism
It is caused by a dominant allele
It is caused by a recessive allele
It is caused by codominant alleles
The pedigree chart shows the inheritance of a genetic disorder in a family.
What conclusion can be made about this genetic disease?
The genetic disorder is dwarfism
It is caused by a dominant allele
It is caused by a recessive allele
It is caused by codominant alleles
The pedigree chart shows the inheritance of a genetic disorder in a family.
It is caused by a recessive allele, h.
What conclusion can be made about the people in the chart?
Peri must have the genotype HH
Sarah Jane must have the genotype Hh
Steven must have at least one H allele
Martha and Ian must have the genotype Hh
Night-blindness is a genetic disorder caused by a dominant allele.
The pedigree chart shows the inheritance of this disorder in a family.
Person X marries someone with normal sight.
What is the probability of them having a child with night blindness?
0%
50%
75%
100%
In a certain plant, the allele fo white fruit (W) is dominant over the allele for yellow fruit (w).
A white-fruited plant was crossed with a yellow-fruited plant.
About half of the offspring were white-fruited and the other half were yellow-fruited.
Which genotypes did the parent plants have?
ww and www
Ww and ww
WW and ww
WW and Ww
In a certain animal, B s the dominant allele for normal skin without spots) and b is the allele for spotted skin.
A pair of these animals is crossed and they produce 37 offspring: 18 with spots and 19 without spots.
What are the most likely genotypes of the parents?
BB x BB
Bb x Bb
Bb x bb
bb x bb
The colour of a mouse's fur is controlled by a single pair of alleles.
A mouse with black fur was crossed with a mouse with white fur. All of the offspring had black fur.
What would be the likely ratio in several generations of offspring, if two of these black offspring were crossed?
1 black fur : 3 white fur
2 black fur : 2 white fur
3 black fur : 1 white fur
4 black fur : 0 white fur
The pedigree chart shows the inheritance of a genetic disorder in a family.
It is caused by a recessive allele.
Which person in this pedigree chart has two possible genotypes?
Martha
Steven
Peri
Jack
How many alleles for each gene are carried in all body cells?
1
2
3
4
