BIO 207 FINAL EVALUATION QUESTIONS WITH SOLUTIONS
GRADED A+ 2025/2026
✔✔What is phenotype? - ✔✔Observable characteristic
✔✔What is genotype? - ✔✔Set of alleles for given phenotype
✔✔What is a homozygote? - ✔✔Individual with two identical alleles
✔✔What is a heterozygote? - ✔✔Individual with two different alleles
✔✔What does a dominant allele with a dash represent? - ✔✔Unknown genotype (Y-
stands for YY or Yy)
✔✔What is the genotype ratio in F2 progeny from a cross of Yy x Yy peas? - ✔✔1:2:1
(1/4 YY, 1/2 Yy, 1/4 yy)
✔✔What is the phenotype ratio in F2 progeny from a cross of Yy x Yy peas? - ✔✔3:1
(3/4 yellow, 1/4 green)
✔✔What is a testcross? - ✔✔Crossing an individual with unknown genotype to a
homozygous recessive individual
✔✔What can a testcross reveal? - ✔✔Unknown genotype of an individual with dominant
phenotype
✔✔What is a phenotype? - ✔✔Observable trait
✔✔What did Mendel's dihybrid crosses reveal? - ✔✔Law of independent assortment
✔✔What are parental types? - ✔✔Chromosomes similar to parents
✔✔What are recombinant types? - ✔✔Chromosomes that are a mix of parents
✔✔What does a dihybrid cross produce? - ✔✔Parental and recombinant types
✔✔What is the phenotypic ratio for P(yellow, round)? - ✔✔9/16
✔✔What does independent assortment in crosses of F1 dihybrids produce? -
✔✔9:3:3:1 phenotypic ratio
✔✔How many possible gametes does each F1 dihybrid produce? - ✔✔Four
, ✔✔What are the four possible gametes produced by YyRr? - ✔✔¼ YR, ¼ Yr, ¼ yR, ¼
yr
✔✔What are the four phenotypic classes that occur in the F2 progeny? - ✔✔Two like
parents, two recombinant
✔✔How would you determine if a mouse with a dominant phenotype is homozygous or
heterozygous? - ✔✔Perform a testcross
✔✔What is a testcross? - ✔✔Cross to a homozygous recessive individual to identify an
unknown genotype
✔✔If all offspring have the dominant phenotype, what is the tested mouse's genotype? -
✔✔Homozygous dominant
✔✔If some offspring have the recessive trait, what is the tested mouse's genotype? -
✔✔Heterozygous
✔✔What is Mendel's law of independent assortment? - ✔✔Different pairs of alleles
segregate independently during gamete formation
✔✔What is the purpose of branched-line diagrams? - ✔✔To show progeny phenotypes
for each gene in different columns
✔✔What can be performed on dihybrids using a testcross? - ✔✔Crossing individuals
with unknown genotype to individuals with both recessive traits
✔✔What is Mendel's law used for? - ✔✔Predicting offspring from complicated crosses
✔✔What is the formula for calculating the number of different gametes? - ✔✔2n, where
n = # of different traits
✔✔How many kinds of gametes are produced from AaBbCcDd? - ✔✔16
✔✔How many genotypes are produced from AaBbCcDd x AaBbCcDd? - ✔✔256
✔✔What is the easier way to do a multihybrid cross? - ✔✔Breaking it down into
independently assorting monohybrid crosses
✔✔Who rediscovered Mendel's work? - ✔✔Carl Correns, Hugo de Vries, Erich von
Tschermak
GRADED A+ 2025/2026
✔✔What is phenotype? - ✔✔Observable characteristic
✔✔What is genotype? - ✔✔Set of alleles for given phenotype
✔✔What is a homozygote? - ✔✔Individual with two identical alleles
✔✔What is a heterozygote? - ✔✔Individual with two different alleles
✔✔What does a dominant allele with a dash represent? - ✔✔Unknown genotype (Y-
stands for YY or Yy)
✔✔What is the genotype ratio in F2 progeny from a cross of Yy x Yy peas? - ✔✔1:2:1
(1/4 YY, 1/2 Yy, 1/4 yy)
✔✔What is the phenotype ratio in F2 progeny from a cross of Yy x Yy peas? - ✔✔3:1
(3/4 yellow, 1/4 green)
✔✔What is a testcross? - ✔✔Crossing an individual with unknown genotype to a
homozygous recessive individual
✔✔What can a testcross reveal? - ✔✔Unknown genotype of an individual with dominant
phenotype
✔✔What is a phenotype? - ✔✔Observable trait
✔✔What did Mendel's dihybrid crosses reveal? - ✔✔Law of independent assortment
✔✔What are parental types? - ✔✔Chromosomes similar to parents
✔✔What are recombinant types? - ✔✔Chromosomes that are a mix of parents
✔✔What does a dihybrid cross produce? - ✔✔Parental and recombinant types
✔✔What is the phenotypic ratio for P(yellow, round)? - ✔✔9/16
✔✔What does independent assortment in crosses of F1 dihybrids produce? -
✔✔9:3:3:1 phenotypic ratio
✔✔How many possible gametes does each F1 dihybrid produce? - ✔✔Four
, ✔✔What are the four possible gametes produced by YyRr? - ✔✔¼ YR, ¼ Yr, ¼ yR, ¼
yr
✔✔What are the four phenotypic classes that occur in the F2 progeny? - ✔✔Two like
parents, two recombinant
✔✔How would you determine if a mouse with a dominant phenotype is homozygous or
heterozygous? - ✔✔Perform a testcross
✔✔What is a testcross? - ✔✔Cross to a homozygous recessive individual to identify an
unknown genotype
✔✔If all offspring have the dominant phenotype, what is the tested mouse's genotype? -
✔✔Homozygous dominant
✔✔If some offspring have the recessive trait, what is the tested mouse's genotype? -
✔✔Heterozygous
✔✔What is Mendel's law of independent assortment? - ✔✔Different pairs of alleles
segregate independently during gamete formation
✔✔What is the purpose of branched-line diagrams? - ✔✔To show progeny phenotypes
for each gene in different columns
✔✔What can be performed on dihybrids using a testcross? - ✔✔Crossing individuals
with unknown genotype to individuals with both recessive traits
✔✔What is Mendel's law used for? - ✔✔Predicting offspring from complicated crosses
✔✔What is the formula for calculating the number of different gametes? - ✔✔2n, where
n = # of different traits
✔✔How many kinds of gametes are produced from AaBbCcDd? - ✔✔16
✔✔How many genotypes are produced from AaBbCcDd x AaBbCcDd? - ✔✔256
✔✔What is the easier way to do a multihybrid cross? - ✔✔Breaking it down into
independently assorting monohybrid crosses
✔✔Who rediscovered Mendel's work? - ✔✔Carl Correns, Hugo de Vries, Erich von
Tschermak
