| A | B |
|---|
| Fetus | a young mammal after fertilization of the egg but before birth |
| Hormones | substances produced by certain glands in the body |
| Menopause | the time in a woman's life when menstruation stops |
| Menstruation | the monthly shedding of blood from the uterus when an egg has not been fertilized |
| Neurons | cells throughout the body that carry signals to and from the brain |
| Organ | body tissues that form a working unit |
| Ovaries | the female organs that make egg cells and hormones |
| Puberty | the time in life when the reproductive organs develop |
| System | a group of organs working together |
| Tendons | tough bands of tissue that attach muscles to bones |
| Testes | the male organs that make sperm cells and hormones |
| Tissue | a group of cells that all do the same job |
| Uterus | the female organ in which a fertilized egg develops into a baby |
