Worksheetsgenes inheritance and variation
Total questions: 20
Worksheet time: 17mins
What are chromosomes?
Long strands of DNA that contain lots of genes.
Different versions of a gene.
The basic unit of heredity; controls a specific trait.
A characteristic passed from parent to offspring
The differences that occur from a mixture of genes
What are alleles?
Long strands of DNA that contain lots of genes.
Different versions of a gene.
The basic unit of heredity; controls a specific trait.
A characteristic passed from parent to offspring
The differences that occur from a mixture of genes
What are alleles?
different gene
different forms of the same gene
different proteins
different cells
What is the definition of homozygous?
Only one type of allele is present in the genotype, eg. BB or bb.
Both dominant and recessive alleles are present in the genotype, eg. Bb.
The alleles that are present, written as letters eg. BB.
What the characteristic actually looks like eg. brown hair.
What is the definition of heterozygous?
Only one type of allele is present in the genotype, eg. BB or bb.
Both dominant and recessive alleles are present in the genotype, eg. Bb.
The alleles that are present, written as letters eg. BB.
What the characteristic actually looks like eg. brown hair.
What are the four bases of DNA?
ATGC
ATDC
GCAS
DNAB
What percent of offspring will have the recessive phenotype?
25
50
75
100
In dogs, the allele for black fur (B) is dominant over the allele for white fur (b). A breeder breeds a heterozygous dog with a recessive homozygous dog. If the female dog has a litter of 12 puppies, predict how many will have black fur.
12
3
6
4
In guinea pigs, the allele for short hair (H) is dominant and the allele for long hair (h) is recessive. When a dominant homozygous male and a heterozygous female are bred together, what is the predicted phenotypic ratio for the offspring?
1:1 short hair to long hair
All have short hair
1:3 short hair to long hair
1:3 long hair to short hair
