TEAS® Science Study Guide

Reproductive System

The reproductive system produces gametes (sex cells) and enables reproduction.

Male

Testes — Produce sperm and testosterone.
Epididymis — Where sperm mature and are stored.
Vas deferens — Carries sperm toward the urethra.
Urethra — Carries sperm out. (In males, the urethra serves both the urinary and reproductive systems.)

Female

Ovaries — Produce eggs (ova) and the hormones estrogen and progesterone.
Fallopian tubes — Carry the egg toward the uterus. Fertilization normally occurs here, not in the uterus.
Uterus — Where a fertilized egg implants and a fetus develops.
Vagina — Birth canal.

Key sequence

Egg released from ovary (ovulation) → fertilized in the fallopian tube → travels to the uterus → implants in the uterine lining. If no fertilization occurs, the lining is shed during menstruation.

Gametes and chromosomes

Body cells have 46 chromosomes. Gametes — sperm and egg — have 23 each, produced by meiosis. When they combine at fertilization, the resulting zygote has the full 46.

Terms to know

Gamete — A sex cell (sperm or egg), with 23 chromosomes.
Zygote — A fertilized egg, with 46 chromosomes.
Ovulation — Release of an egg from the ovary.
Meiosis — Cell division that produces gametes with half the chromosome number.

What the TEAS asks most

Where does fertilization normally occur? Fallopian tube.
How many chromosomes are in a human gamete? 23.
Which organ produces eggs and estrogen? Ovaries.
What is a fertilized egg called? Zygote.