Page 62 - 86 human physiology part-2

The Endocrine System

• Liver and kidney disorders
• Hypertension (high blood pressure)
• Decreased sperm count and impotency
• Aggressive behavior ("roid mania)
• Balding
• Acne

Female

The ovaries produce estrogen and progesterone. Estrogen increases at the time of puberty and
causes the growth of the uterus and vagina. Without estrogen egg maturation would not occur. Estrogen
is also responsible for secondary sex characteristics such as female body hair and fat distribution.
Estrogen and Progesterone are responsible for the development of the breast and for the uterine cycle.
Progesterone is a female hormone secreted by the corpus luteum after ovulation during the second half
of the menstrual cycle. It prepares the lining of the uterus for implantation of a fertilized egg and allows
for complete shedding of the endometrium at the time of menstruation. In the event of pregnancy, the
progesterone level remains stable beginning a week or so after conception.

Pineal gland

The pineal gland (also called the pineal body or epiphysis) is a small endocrine gland in the brain.
It is located near the center of the brain, between the two hemispheres, tucked in a groove where the
two rounded thalamic bodies join.

The pineal gland is a reddish-gray body about the size of a pea (8 mm in humans) located just
rostro-dorsal to the superior colliculus and behind and beneath the stria medullaris, between the
laterally positioned thalamic bodies. It is part of the epithalamus.

The pineal gland is a midline structure, and is often seen in plain skull X-rays, as it is often
calcified. The main hormone produced and secreted by the pineal gland is melatonin. Secretion is
highest at night and between the ages of 0-5.

Glossary

Adrenal Gland: endocrine gland that is located on top of each kidney

Amino Acid-derived: hormones that are modified amino acids

Antagonistic Hormones: hormones that act to return body conditions to within acceptable limits
from opposite extremes

Calcitonin: hormone produced by the thyroid; contributes to the regulation of blood calcium
levels

Eicosanoids: lipids that are synthesized from the fatty acid chains of phospholipids found in
plasma membrane

Wikibooks | 277