Immune System

Macrophage: Type of white blood cell that attacks foreign invaders in the body. They help to destroy bacteria, tumors, etc. Helps other cells in the body respond in the immune system.

T Helper Cells: A type of white blood cell that recognizes antigens (any foreign substance that can enter the body) releasing cytokines that activate B+ killer T cells.

B Cells: Lymphocytes playing a large role in the immune system response. Will release antibodies to fight off antigens.

Antibodies: Proteins that bind to an antigen and neutralizes it.

Killer Cells: Destroys antigens that are discovered by our antibodies.

Cytotoxic T Cells: Type of T-cell which kills cells that are infected with viruses and other pathogens.

Memory Cells: Immune cells (long lifespans) remembering attacks by certain atigens. When these antigens return, memory cells trigger a quick immune system response before the body experiences the symptoms.

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Asthma: For some, their lungs are sensitive to and experience allergic responses pollen/dander/etc. The breathing tubes in the lungs narrow restricting airflow and an individual experiences difficulty breathing.

DiGeorge Syndrome: This is a birth defect, where children are born with out a thymus gland. The thymus gland is where T-cells normally mature, and this syndrome is an example of a T-lymphocyte disease.

Aging

When it comes to aging, both genetics and lifestyle impact it.

GENETICS

In the 1960's Leonard Hayflick discovered that aging occurs on a cellular level. Cells divide and replicate over the course of our lives, but eventually loses the ability to divide and repair itself. The loss of this ability to divide is known as cellular senescence. One possible cause of aging is the degradation of telomeres, which are the pieces that caps the end of each chromosome. As the cell continues to divide, the telomeres become shorter and eventually become so short that a cell cannot reproduce anymore

HDL (known as the "good cholesterol") has the main purpose of transporting LDL (known as the "bad cholesterol") throughout our blood vessels. People with larger amounts of HDL in their body have higher chances of living longer because of the decreased risk of dying due to cardiovascular failures.

LIFESTYLE

Lifestyle decisions also play a large role in aging. An individuals decisions concerning things in their life such as exercise, healthy eating, stress, hygiene, health, and drug abuse can all impact how quickly (or slowly) they age.

WORKS CITED

CBS News Staff. (2009, September 12). Resveratrol Video. Retrieved May 9, 2010 from http://www.youtube.com/watch?v=fWkRN-0KjeM&feature=player_embedded

Nova Staff. (2007, January 9). Aging. Retrieved May 9, 2010 from http://www.pbs.org/wgbh/nova/sciencenow/3401/01.html

(2002, September 16). Genetics of Aging. Retrieved May 23, 2009 from http://web.riverdeep.net/current/2002/09/091602t_oldflies.jhtml