Monohybrid Crosses

The physical expression of a genetic trait is called a

• mutation

• genotype

• crossing over

• phenotype

The following items are examples of __________.

Items: eye color, hair color, height

• homozygous alleles

• genotype

• heterozygous alleles

• phenotype

having two of the same genes for the trait (sometimes called purebred).

• homozygous
• hetrozygous
• protein
• chromosome

having two different genes for a trait (sometimes called hybrid).

• protein
• homozygous
• heterozygous
• genotype

An allele whose trait only shows up when no dominant allele is present.

• hidden allele
• dominant allele
• recessive allele
• present allele

Which of the following genotypes would be considered heterozygous?

• BB
• gg
• Ff
• TT

Which of the following alleles is homozygous recessive?

• Tt
• tt
• TT
• T

An allele whose trait always shows up in the organism when the allele is present.

• recessive allele
• dominant allele
• hidden allele
• present allele

T - tall and t = short
In the punnett square below, what belongs in the missing square

• tt
• Tt
• Bb
• TT

B=brown eyes
b= blue eyes
What is true about these two brothers that have brown eyes:
One has genotype BB the other Bb.

• they have same phenotype and genotype
• they have different genotypes and phenotypes
• they have same phenotype but different genotypes
• they have same genotype but different phenotypes