Unit 5, Section 1 Summary

Section 1 – Human Reproduction

 Sexual reproduction produces babies.  Reproductive cells must combine.

Sex characteristics –

Primary – are the physical differences between male and female reproductive organs.

Secondary – are the differences that occur during puberty between the sexes. For example – women’s breasts get larger, her body gets rounder and her hips get wider. Also she gets body hair under her arms and in the pubic area. This usually happens between 10 and 14 years of age.

A boy’s voice gets deeper, his muscles get bigger and his shoulders wider. He gets hair on his body and his face. This happens between 11 and 16 years old.

Reproductive cells are called gametes. The female gametes are called egg cells. They are produced in the ovaries. Women have 2. A mature woman produces a mature egg cell every 28 days or so, until she is older, around 55 years old.

The egg cell is big and round. It has a nucleus.

The male gametes are called sperm cells. They are produced in the testicles. Men have 2. They produce millions of sperm cells during puberty and continue to produce them for their entire lives.

The sperm cell is small and looks like a snake.