Monohybrid
A trait has a dominant allele (A) and a recessive allele (a). What is the genotype of a heterozygous individual?
Aa
How many traits are studied in a dihybrid cross?
Two
In complete dominance, which allele determines the phenotype?
The dominant allele
How many daughter cells are produced by meiosis?
Four
What does DNA stand for?
Deoxyribonucleic Acid
What is the phenotype of an individual with genotype Bb if B is black and b is brown for fur colour?
Black
What gametes can be produced by an individual with genotype AaBb?
AB, Ab, aB, ab
What pattern of inheritance produces pink flowers from red × white flowers?
Incomplete dominance
What is the chromosome number of a gamete called?
Haploid (n)
What is the name for different versions of a gene?
Alleles
What are the possible gametes produced by an Aa individual?
A and a
How many resulting gametes does a dihybrid cross create?
16
What pattern of inheritance is shown by the AB blood group?
Codominance
During which stage does crossing over occur?
Prophase I
What is the location of a gene on a chromosome called?
Locus
A cross between Aa × Aa is performed. What is the probability of an offspring being aa?
25% (1/4)
What is the expected phenotypic ratio of AaBb × AaBb when genes are unlinked and show complete dominance?
9:3:3:1
What is it called when more than two alleles can code for a single trait?
Multiple alleles
What process causes homologous chromosome pairs to line up randomly during meiosis?
Independent assortment
Genes that are close together on the same chromosome are said to be ________.
Linked
A monohybrid cross produces offspring in a 3:1 phenotype ratio. What were the genotypes of the parents?
Both parents were heterozygous (Aa × Aa)
What is the expected phenotype and genotype ratio of a test cross performed on a Dihybrid heterozygote?
1:1:1:1 (for both)
Why does a heterozygous individual show an intermediate phenotype in incomplete dominance?
Neither allele completely masks the other
Explain how crossing over increases genetic variation.
DNA is exchanged between non-sister chromatids, creating new allele combinations. (must mention non-sister chromatids)
Why do linked genes often produce more parental phenotypes than recombinant phenotypes?
Crossing over is less likely to occur between closely spaced loci, so the genes are usually inherited together.