Bio 7.8 - What Makes your Heart Beat not Beat?

blood pressure

• ventricles pump blood each time they contract

• arteries have elastic, expandable walls to withstand this pressure

• force of blood against blood vessel walls is known as BP

• normally measured along brachial artery of arm

systolic pressure (or systole)

• pressure when ventricles contract

• highest blood pressure reading (top number)

diastolic pressure (diastole)

• blood pressure when heart is at rest

• lowest blood pressure reading (bottom number)

pulse

• as blood is pumped through arteries, arterial walls swell, and then recoil

• swelling can be felt in any artery that runs close to the surface

hypertension

• high high blood pressure (eg 140/90, 125/90)

CONTRIBUTING FACTORS

• plaques formed by fatty deposits from undigested foods - line the walls of the arteries and make radius smaller - increasing blood pressure

• high salt intake - retain water - greater fluid volume leads to blood in greater volumes - increased blood pressure

• stress

• smoking

• age, sex, race

• stimulants

• lack of excercise

• diet

CAUSE:

• vitamin deficiency in cells of arteries which results in thickening and spasms of arterial walls 

PREVENTION

• optimum intake of nutrients: vitamin C, Arginine (sesame seeds), coenzyme Q-10 (fatty fish), magnesium (leafy greens)

hypotension

• low blood pressure (eg. 90/60)

REASONS

• cuts or amputation, drugs, hormones

WHAT

• blood does not reach all organs

• proper kidney function can only be maintained if there is sufficient pressure for filtration

• body can adjust blood pressure to some degree

FIX

• monitored by hypothalamus in the brain

• body can dialate/widen arterioles thus lower BP in them or constrict them to raise BP

• known as homeostasis

harmful habits which increase heart disease risk

• smoking

• being inactive

• carrying too many pounds

• eating poorly

• drinking too much alcohol 

• can derange metabolism and change how cells and tissues work

• disturb cholesterol, blood sugar, BP

• lead to heart attack, stroke, peripheral artery disease, valve problems, aortic aneurysm, heart failure

• also damage kidneys, bones, and brain