CK12 Life Science

Growth and Development of the Fetus Table(22.1) also shows changes that take place after the embryo becomes a fetus. Compare the ...

Figure 22.7: This fetus is 38 weeks old and ready to be born. Surrounding the fetus is the fluid-filled amniotic sac. The placen ...

Infancy and Childhood The first year after birth is calledinfancy. Infancy is a period of very fast growth. During infancy, the ...

From age three until the teens, growth is slower. The body also changes shape. The arms and legs get longer relative to the trun ...

In boys, puberty begins when LH from the pituitary gland triggers the testes to secrete testosterone. Testosterone causes the pe ...

Figure 22.10: These teens are good friends. Like most teens, they spend more time with one another than they do with family memb ...

adulthood. For example, heart disease, cancer, and diabetes become more common during this time. This is the stage of life when ...

Figure 22.11: This family picture shows women in each of the three stages of adulthood. Which stage does each woman represent? W ...

Why doesn’t a doctor wait for a newborn baby to breathe on its own before cutting the umbilical cord? Explain how pituitary hor ...

fertilization Union of a sperm and egg; occurs in a fallopian tube. fetus Stage of a developing baby between the end of the 8thw ...

Introduction A healthy reproductive system is important for two reasons. It is important for overall good health. It is also imp ...

Bacterial STDs In the U.S.,Chlamydiais the most common STD caused by bacteria. Females are more likely than males to develop the ...

Viral STDs Genital wartsare an STD caused by human papilloma virus, or HPV. They are one of the most common STDs in teens. HPV i ...

lead to liver cancer. Medicines can help prevent liver damage in these people. There is also a vaccine to prevent hepatitis B. H ...

Figure 22.14: Do you see the wormlike structures under the skin of the scrotum shown here? They are swollen veins, called varico ...

possible cause of vaginitis is a yeast infection. Yeast normally grow in the vagina. A yeast infection occurs when the yeast mul ...

Figure 22.16: Ovarian cysts, like this one, are common. They generally do not need to be treated unless they cause symptoms. Mos ...

testes (Figure22.17). You can learn how to do the exam athttp://www.5min.com/Video/ Testicular-self-examination-1353 If you have ...

Lesson Summary Sexually transmitted diseases are caused by pathogens. They spread through sexual contact. In males, other disor ...

http://wrongdiagnosis.com/h/hepatitis_b/prevalence.htm http://wrongdiagnosis.com/s/syphilis/prevalence.htm http://www.cdc.gov/s ...