Answer to Question 1
The relationship between salt intake and blood pressure is directas chronic sodium intakes increase, blood pressure rises in a stepwise fashion. Once hypertension sets in, the risk of death from stroke and heart disease climbs steeply. High intakes of salt among the world's people correlate with high rates of hypertension, heart disease, and strokes. Over time, a high-salt diet may damage the linings of blood vessels in ways that make hypertension likely to develop. People who need to reduce their blood pressure for their health's sake are urged to cut their sodium intake. People with hypertension, diabetes, or chronic kidney disease should take in no more than 1,500 milligrams per day because this level of restriction often lowers blood pressure. Even without meeting the recommended levels, reducing sodium by at least 1,000 milligrams per day reduces blood pressure. This is a worthy goalhypertension is a leading cause of death and disability in this country.
Answer to Question 2
From birth to about age 20, the bones are actively growing. Between the ages of 12 and 30 years, the bones achieve their maximum mineral density for lifethe peak bone mass. Beyond those years, bone resorption exceeds bone formation, and bones lose density. Some bone loss is an inevitable consequence of aging. Sometime around age 30, the skeleton no longer adds significantly to bone density. After about age 40, regardless of calcium intake, bones begin to lose density.
An example of a homeostatically controlled variable: blood levels of glucose in a human.
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Humoral control of blood sugar levels.
The air intake tube is being removed from the throttle body.
Measuring blood pressure with an aneroid manometer
White Blood Cells