Grade 8 · Science

Grade 8 Science — Genetics questions and answers

Genes, DNA, Punnett squares, and traits. Written in American English for students, parents, and teachers in the United States.

Practice quiz

Question and answer list

Open a card to see the answer. These are original practice items for US elementary students — not a state test copy.

1. Genes are made of

Answer: DNA

DNA carries hereditary information.

2. A trait is

Answer: a characteristic that can be inherited

Eye color is a classic example.

3. Alleles are

Answer: different versions of a gene

You inherit alleles from each parent.

4. In a Punnett square, a capital letter often means

Answer: a dominant allele

Dominant traits can show with one copy.

5. A recessive trait shows when

Answer: both alleles are recessive

Two lowercase letters, like aa.

6. Genotype is the

Answer: allele combination

Phenotype is what you see.

7. Humans typically have how many chromosomes in most body cells?

Answer: 46

Gametes have 23.

8. Mitosis produces

Answer: two identical body cells

Meiosis makes sex cells.