AGE AND CELLSAnatomy/Physiology

Geriatrics-care of elderly and their medical problems

What causes cells to age?

1. Genetic clock-most cells go through mitosis except skeletal & nervous. Eventually others stop

2. Telomeres-on tip of chromosomes for protection. Eventually they shorten & disappear. The erosion contributes to aging

3. Glucose links between protein molecules over time and adds to losss of elasticity .

4. Free radicals-ions with extra oxygen (superoxide). Result from chem/sun exposure. Antioxidants counteract these.

Ex. Wrinkled skin, stiff joints

Aging Diseases

Progeria-telomeres shorten, dry and

wrinkled skin,

baldness, death

at around 13 years

of age

Werner Syndrome-genetic disorder, wrinkled skin, graying hair/baldness,

Cataracts, muscular atrophy, death before 50

Cancer-abnormal, uncontrolled cell growth

Tumor-excess tissue (malignant vs. benign) Metastasize-spread to other parts of body Oncologist-treats/studies cancer

Aging process begins at maturity-we don’t know what causes it.

Chemical insults-presence of toxic chemicals like alcohol, tobacco, drugs, CO or absence of glucose or Oxygen

External physical factors-UV light, x-rays Genetically programmed-traits run in

families

Certain events happen as we get older

1. Epithelial tissue becomes thinner, loses elasticity, sags

2. Connective tissue-collagen declines, bones become porus, weak

3. Muscle and nervous tissue-decline due to circulation, less oxygen

Some changes occur at anytime in life. Neoplasm-abnormal mass of growing cells

that could be malignant or benign Hyperplasia- body tissue enlarged b/c of a

stimulus (breasts during pregnancy due to hormones)

Atrophy- tissue decreases due to lack of stimulation. (muscles not used will atrophy)