Genetics and Biotechnology Review

Having two of the same genes for the trait (TT, tt); Both dominant or both recessive.

• homozygous or purebred
• heterozygous or hybrid
• twin offspring
• pairs of chromosomes

Which of the following alleles is homozygous (purebred) recessive?

• Tt
• tt
• TT
• t

Two brown eyed parents (Bb) have a baby. What is the chance the baby is blue eyed?

• 0 %
• 25%
• 50%
• 75%

Which of the following is a phenotype?

• Aa
• red hair
• heterozygous genes
• mutated DNA

Aa is

• homozygous (purebred)
• heterozygous (hybrid)

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

A dog gives birth to 5 puppies. What percentage of the chromosomes does each puppy share with the mother?

• 25%
• 50%
• 75%
• 100%

Evan is a tall, 12 year old boy. He has a scar on his right cheek. He is intelligent and an excellent drummer. Which of his traits did he most likely inherit?

• height
• the scar
• his intelligence
• ability to play drums

Where is DNA in a eukaryotic cell?

• Cytoplasm
• Cell membrane
• Nucleus 
• Vacuole

In a heterozygous genotype, the ___________ allele takes over in the phenotype.

• recessive
• dominant
• lower case letter
• both