Chromosomes Vocabulary

Haploid (1n)

A cell that has only one set of chromosomes. In humans, this is seen in gametes (sperm and egg cells), which each have 23 chromosomes.

Diploid (2n)

A cell that has two sets of chromosomes, one from each parent. Somatic cells (non-reproductive cells) in humans are diploid and have 46 chromosomes (23 pairs).

Haploid (1n)

A cell that has only one set of chromosomes. In humans, this is seen in gametes (sperm and egg cells), which each have 23 chromosomes.

Diploid (2n)

A cell that has two sets of chromosomes, one from each parent. Somatic cells (non-reproductive cells) in humans are diploid and have 46 chromosomes (23 pairs).

Male Gonads

Testes

Female Gonads

Ovaries

Gametes

Reproductive cells that are haploid.

Male Gametes

Sperm cells.

Female Gametes:

Egg cells.

Homologous Chromosomes:

Pairs of chromosomes (one from mom, one from dad) that are similar but may have different versions of a gene.

Double-Stranded Chromosome:

A chromosome made of two identical parts after DNA replication.

Sister Chromatids

Identical halves of a duplicated chromosome that are stuck together at the centromere.

Homologous Pair

A pair of chromosomes, one from each parent, that are similar in shape and size.

Nucleosomes:

DNA wrapped around proteins, like beads on a string, that help pack the DNA.

Histones

• The proteins that DNA wraps around to form nucleosomes.