| A | B |
|---|
| Reproduction | Process by which living things produce individuals of the same kind |
| Sexual Reproduction | The reproductive process that requires 2 parents and produces offspring that are a 50/50 combination of both parents |
| Asexual Reproduction | The reproductive process that requires only 1 parent and produces offspring that are 100% identical to that parent |
| Gametes | Sex cells; the sperm and the egg |
| Sperm | Male sex cells |
| Egg | Female sex cell |
| Chromosome | Rod-shaped cell structure that contains DNA and passes on genetic information to new cells (X). |
| Testes | male sex glands that produce sperm |
| Testosterone | Male secondary sex hormone |
| Ovaries | Female sex glands that produce eggs |
| Estrogen | Female secondary sex hormone |
| Fertilization | Joining of the egg and the sperm nuclei |
| Gestation Period | The length of pregnancy |
| Zygote | The shortest stage of development after fertilization |
| Embryo | Stage of development from 3 days to 8 weeks |
| Fetus | Longest stage of development, from 8 weeks until birth |
| Infancy | Stage of development that lasts from 1 month to about 2 years of age |
| Childhood | Stage of development that begins at about 2 years of age and continues until age 13 |
| Adolescence | Stage of development that begins at age 13 and ends at age 20 |
| Puberty | Beginning of adolescence and the onset of secondary sex characteristics |
| Adulthood | Stage of development that begins at age 20 and lasts the rest of a person's life |
