Saturday, May 29, 2010

Ovarian and Uterine Cycles

Uterine cylce: lining of ueterus builds and exits the body through the vagina(menstruation)

Ovarian Cycle: mature egg travels to the uterus

LH: aka luteinizing hormone released in the pituitary gland and causes ovulation (when follicle release and egg)

Progesterone: released by the ovaries when an egg is released from an ovary. Prepares unterine lining or endomitrium for the occurance of a fertilized egg.

FSH: aka folicle stimulating hormone from pituitary gland controls sexual maturation and reproductive system

Estrogen: Responsible for the developement of secondary sex characteristics in women. Released in larger amounts when folicles grow and then helps to thicken the uterine lining. when there is more estrogen the pituitary gland releases LH and FSH

GnRH: aka gonadotropin releasing hormone released by the hypothalamus causes FSH and LH to be released

hCG: aka human chronic hormone released when egg has been fertilized

menstruation and pregnancy: hormone levels high during pregnancy

negative feedback loop: decrease of hormones in the body

positive feedback loop: increase in hormones because the egg is released into the uterus and more hormones are needed to aid in the developement of the fetus.

first trimester: zygote divides into millions and millions of cells then officially becomes a fetus and begins to develop internal organs

second trimester: fetus develops lungs and brains

third trimester: fetus reaches full maturity and is able to function outside of the uterus

Friday, May 14, 2010

The Immune System

macrophage: a kind of white blood cells that consumes foreign invaders in the body. Help destroy bacteria and tumor cells. It also helps other cells in the immune system take action

antigen: any foreign substance that enters the body

T helper cell: white blood cell that recognizes the presence of antigens and releases cytokines that activate B and killer T cells.

B cell; lymphocyte that turns into plasma in the pressence of some antigens and releases antibodies to help fight off foreign invaders.

antibodies: protein that binds to an antigen, thus neutralizing it.

killer cells: destroy antigens that have been discovered by antibodies.

Cytotoxic T cell: type of T cell that kills cells that have been infected with viruses and other pathogens

memory cells: immune cells with long lifespans that remember attacks by certain antigens. When antigens return they can trigger a speedy immune response often before symptoms are felt.

Asthma: sensitive lungs have an allergic response to pollen and dander and the like and breathing tubes in the lungs become significantly narrower, thus restricting airflow.

eczema: also called atopic dermatitis is an uncomfortable, often reddish rash that often occurs in people with asthma.

Saturday, May 1, 2010


Though the quest for the fountain of youth is age old, it still seems to be quite elusive and seemingly inexplicable. There have been people that smoke and drink and eat fattening foods and live to 100. But, there are also people that eat healthy and exercise, have no vices, and only live to thirty.

Biological aging is believed by scientist to be cause by the breakdown of telomeres. Telomeres are pieces of DNA at the ends of chromosomes that protect the chromosomes. As cells divide over time, the telomeres get shorter, and thus less able to do their job.

There have recently been some discoveries on specific factors that may lead to increased life spans. On studies performed on some of the lucky people to live past 100, it was found that these people all contained high amounts of HDL. HDL is the good cholesterol, the kinds that helps rid the body of the bad cholesterol. A decrease in bad cholesterol leads to decreased risks of heart disease and diabetes. Such elevated levels of HDL is likely to be genetic.

Though many scientists argue that aging is an extremely complex process that involves a multitude of genes, some think that it might be much more simple. The sirtuin gene seems to do a pretty effective job on its own of impeding the aging process. When this gene is triggered, the body goes into a sort of survival mode, significantly increasing cell health. The question now seems to be how to trigger the gene. Risveritrol, the healthy chemical found in red whine, is thought to turn on the gene and lead to a healthier lifespan. Others suggest that the hunger caused by extreme dieting will throw the body into this survival mode.

There are also simple lifestyle choices (other than severe caloric restrictions) that may help slow the aging process. Avoid the following:



high cholesterol intake

drug use

sedentary lifestyle



Nova Staff. (2007, January 9). Aging. Retrieved May 1, 2010 from
Moisse, Katie. (2010, February 8). Researchers Identify Genetic Variant Linked To Faster
Biological Aging. Retrieved May 1, 2010 from
Park, Alice. (2010, February 11). How to Live 100 Years. Retrieved May 1, 2010from http://,28804,1963992_1933665,00.html