An asthma attack

Ovulation Animation

This animation shows the process of ovulation (the release a single egg cell from an ovary). Ovulation occurs though a sequence of hormonal responses. Located deep within the brain, the pituitary gland releases the hormones FSH and LH, which travel through the blood stream to the ovaries. These hormones signal the development and release a single egg cell from one of the ovaries. The sweeping motion of the fimbriae draws the egg cell through a very small space in the open body cavity into the uterine, or fallopian, tube. The egg cell will either be fertilized by sperm or will dissolve if fertilization does not take place.

• Women's Health

Baby

A baby's soft spots (fontanels) close when the skull bones fuse together. See how.

Arthroscopic knee surgery

Arthroscopic knee surgery — watch video of an arthroscopy procedure.

Barium enema

See what to expect during an X-ray examination of your colon.

Bent-over row with dumbbell

The bent-over row with dumbbell targets the back of the shoulder. See how it's done.