Genetics Review

Front

How many pairs of chromosomes do humans have?

Back

Humans have 23 pairs of chromosomes.

Front

What are the different variations of a gene?

Back

The different variations of a gene are called alleles.

Front

What does homozygous mean?

Back

Homozygous means when an offspring has 2 of the same alleles for a trait.

Front

What is the physical expression of a trait?

Back

The physical expression of a trait is called phenotype.

Front

What does heterozygous mean?

Back

Heterozygous means when an organism has two different alleles for a trait (e.g., Tt).

Front

What is a gene?

Back

A gene is a segment of DNA that contains the instructions for building a specific protein.

Front

What is a chromosome?

Back

A chromosome is a long strand of DNA wrapped around proteins, containing many genes.

Front

What is a genotype?

Back

A genotype is the genetic makeup of an organism, represented by the alleles it possesses.

Front

What is a mutation?

Back

A mutation is a change in the DNA sequence that can lead to changes in traits.

Front

What is a dominant allele?

Back

A dominant allele is an allele that expresses its trait even when only one copy is present.