Chapter 11Maintaining Homeostasis

Your body is always responding to changes that occur in the environment around you.

Homeostasis: the ability of your body to maintain an internal balance

What are some body functions that homeostasis controls?

Keeping an Internal Balance

Enzyme Levels: Control the release of energy from food molecules in the mitochondria

Waste Product Levels: Eliminating carbon dioxide through breathing and getting rid of toxic materials through the kidneys

Blood Sugar Level: After eating a meal, our body releases insulin. Insulin returns glucose levels to its optimal level.

Keeping an Internal Balance

Concentration of Substances in Blood: Organs and systems have a role to play in distributing and disposing various materials.

Heart Rate: During times of stress your heart rate increase to deliver more blood to cells

Water Balance: Special hormones balance water and mineral levels in the body. 65-70% of our bodies are made up of water.

Keeping an Internal Balance

Diet, exercise levels and lifestyle can deeply interfere with homeostasis.◦ Poor diet, low exercise levels, and bad lifestyle

choices make it difficult for your body to perform effectively and efficiently

Genetics can also have a large impact on homeostasis

What Affects Homeostasis?

Diabetes (Lifestyle and Genetics)◦ People with diabetes have abnormally large

amounts of sugar in the blood and urine. ◦ Type 1 Diabetes – people cannot produce insulin◦ Type 2 Diabetes – people can produce insulin, but

the body does not use it properly

Ulcers (Genetics)◦ Consist of holes or breaks in the lining of the

esophagus or stomach.◦ This causes people to feel a burning or aching

sensation in the lower chest region

When Your Body Cannot Cope

Heart Attack (Lifestyle and Genetics)◦ Blood flow to the arteries is restricted. The heart

fails to pump steadily. As a result, heart tissues begin to die.

Anorexia and Bulimia

When Your Body Cannot Cope

Angiogram – provides an X-ray picture of blood vessels

Angioplasty – clears blocked arteries Pacemaker – releases an electrical charge to

stimulate a steady heartbeat Jarvik 7 – first artificial heart. Colonoscopy – provides a view of the lower

digestive tract. Kidney dialysis – a system of tubing allows

blood to flow into a machine to be cleaned.

Technology That Maintains Homeostasis