Steps of a genetic diagram?
Reveal answer
Parent genotypes → gametes → Punnett square → offspring genotypes → phenotypes + ratio.
Key words: gametes
4(b) INHERITANCE · RECALL
4.23 Monohybrid inheritance diagrams
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Ratio from Aa × Aa?
Reveal answer
3 : 1 dominant : recessive.
Key words: 3 : 1
Offspring genotypes from AA × aa?
Reveal answer
All Aa (heterozygous).
Key words: Aa
What is meant by the term monohybrid cross?
Reveal answer
Inheritance model following one gene locus.
Key words: monohybrid cross
What is meant by the term Punnett grid?
Reveal answer
Diagram combining possible parental gametes.
Key words: Punnett grid
What is meant by the term genotypic ratio?
Reveal answer
Relative frequencies of offspring allele combinations.
Key words: genotypic ratio
What is meant by the term phenotypic ratio?
Reveal answer
Relative frequencies of observable outcomes.
Key words: phenotypic ratio
Cross workflow: for Alleles, give the action and the purpose.
Reveal answer
Action: Define symbols. Purpose: Removes ambiguity.
Key words: Alleles
Cross workflow: for Parents, give the action and the purpose.
Reveal answer
Action: Write genotypes. Purpose: Sets the cross.
Key words: Parents
Cross workflow: for Gametes, give the action and the purpose.
Reveal answer
Action: One allele per gamete. Purpose: Applies segregation.
Key words: Gametes
Cross workflow: for Offspring, give the action and the purpose.
Reveal answer
Action: Combine gametes. Purpose: Lists possible genotypes.
Key words: Offspring
Cross workflow: for Interpretation, give the action and the purpose.
Reveal answer
Action: Count and convert to phenotype. Purpose: States probability/ratio.
Key words: Interpretation
True or false, and why? “A Punnett grid predicts the exact next child.”
Reveal answer
False. It gives probabilities for each fertilisation event.
True or false, and why? “A heterozygous gamete is Aa.”
Reveal answer
False. A haploid gamete carries one allele, A or a.
True or false, and why? “Four boxes mean a parent will have four children.”
Reveal answer
False. Boxes represent possible combinations, not family size.