Genetic crosses (AQA GCSE Biology): Quizzes
📚Quizzes
Practise the questions
12 questions from this quiz
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Practise the questions
12 questions from this quiz
What are the two main tools used to predict offspring traits in genetic crosses?
What are the two main tools used to predict offspring traits in genetic crosses?
Genetic diagrams & Punnett squares
What does heterozygous mean?
What does heterozygous mean?
Having two different alleles
How are dominant alleles represented in genetic diagrams?
How are dominant alleles represented in genetic diagrams?
Capital letters
When does a recessive trait show in offspring?
When does a recessive trait show in offspring?
With two copies of recessive allele
What is a Punnett square?
What is a Punnett square?
A grid showing gamete combinations
What is the first step in using a Punnett square?
What is the first step in using a Punnett square?
Write gametes from one parent on top
If 3 out of 4 offspring have purple flowers, what is this as a percentage?
If 3 out of 4 offspring have purple flowers, what is this as a percentage?
75%
Why might actual results differ from genetic predictions?
Why might actual results differ from genetic predictions?
Chance variation affects real results
In a cross Rr × Rr (R=purple, r=white), what % of offspring will be purple?
In a cross Rr × Rr (R=purple, r=white), what % of offspring will be purple?
75%
In a cross Gg × gg for pod colour (G=green, g=yellow), what % will be yellow?
In a cross Gg × gg for pod colour (G=green, g=yellow), what % will be yellow?
50%
What is the phenotype ratio (black:brown) in a Bb × Bb rabbit fur cross?
What is the phenotype ratio (black:brown) in a Bb × Bb rabbit fur cross?
3:1
In a Bb × Bb cross, what fraction of offspring are heterozygous with black fur?
In a Bb × Bb cross, what fraction of offspring are heterozygous with black fur?
1/2