Answer to Question 1
Many observational studies suggest that elevated levels of the amino acid homocysteine may be an independent risk factor for heart disease, heart attacks, and sudden death in patients with heart disease; findings from prospective studies, however, are far less conclusive. Researchers do not yet fully understand the many factorsincluding a diet high in saturated fatty acidsthat can raise homocysteine in the blood or whether elevated levels are a cause or an effect of heart disease. Elevated homocysteine is associated with increased oxidative stress and inflammation. Until researchers can determine the exact role homocysteine plays in heart disease, they are following several leads in pursuit of the answers. Coffee's role in heart disease has been controversial, but research suggests it is among the most influential factors in raising homocysteine, which may explain some of the adverse health effects of heavy consumption. Elevated homocysteine levels are among the many adverse health consequences of smoking cigarettes and drinking alcohol as well. Homocysteine is also elevated with inadequate intakes of B vitamins and can usually be lowered with fortified foods or supplements of vitamin B12, vitamin B6, and folate. Lowering homocysteine, however, may not help in lowering risks or preventing heart attacks. Supplements of the B vitamins do not always benefit those with heart disease and, in fact, may actually increase risks
Answer to Question 2
An essential amino acid supplied in less than the amount needed to support protein synthesis is called a limiting amino acid. Four amino acids are most likely to be limiting: lysine, methionine, threonine, tryptophan
Relationship between Hox gene number and body complexity in different types of animals.
Human Heart Cir
The heart: (a) coronary arteries and veins
Major fluid compartments in the body.
Anatomy of the heart. Remember: It is labeled right and left based on the patient’s perspective.
Chambers of the Heart