Health and Diseases Questions and Answers

About Health and Diseases

Medium ~90 min study

Most of this book describes how the body works. This chapter describes what goes wrong with it, and in particular the conditions that people bring on themselves or can protect themselves against. That practical emphasis runs throughout: almost every disorder named here comes with something that can be done about it.

The first section deals with substances. Drug addiction is the regular habitual use of certain drugs. Tobacco is used for smoking, chewing and snuffing, and nicotine is the component that acts on the body. Alcohol dependence is alcoholism, and prolonged use depresses the nervous system and damages the liver. In each case the chapter separates the immediate effect from the long term one, which is a distinction the questions test directly.

The second section covers disorders that are not passed from person to person. Cancer is uncontrolled cell division forming a tumour, and its types are named by the tissue affected. Diabetes mellitus, obesity and coronary heart disease follow, each with its own cause. AIDS closes the chapter, as the one infectious disease treated here, along with the awareness work of NACO and World AIDS Day.

What you'll learn

• Define drug addiction and name the ways tobacco is used.
• State the effects of nicotine and of alcohol on the body.
• Separate the immediate effect of alcohol from its long term effect.
• Name the four types of cancer by the tissue each affects.
• Distinguish a malignant tumour from a benign one using metastasis.
• Explain the cause of diabetes mellitus and name its classic symptoms.
• State the cause of coronary heart disease and of obesity.
• Name the causative agent of AIDS and the body that spreads awareness of it.

Before you start

• Basic knowledge of the organ systems, particularly the heart, liver and nervous system.
• An understanding of cell division from earlier chapters.
• Familiarity with hormones and what insulin does.

Health and Diseases explained

What this chapter covers

Drug addiction and abuse

The use of certain drugs by an individual as a regular habit is called drug addiction or drug abuse. The chapter distinguishes this habitual use from the legitimate medical use of the same substances, and it introduces the psychotropic drugs that act on the mind.

Tobacco and its effects

Tobacco is used for smoking, chewing and snuffing, and inhaling tobacco smoke is specifically called smoking. Nicotine is the component that stimulates the adrenal gland to secrete adrenaline. Tobacco smoke is linked to several diseases, and World No Tobacco Day on the thirty first of May marks the effort to reduce its use.

Alcohol and alcoholism

The dependence on alcohol is called alcoholism and the addict is termed an alcoholic. Alcohol acts immediately on the central nervous system, depressing it by behaving as a sedative and analgesic substance. Over a long period it causes fatty liver, which leads to cirrhosis. Separating the immediate nervous effect from the delayed liver damage is important.

Cancer and its types

Cancer is an abnormal and uncontrolled division of cells that invade and destroy surrounding tissue, forming a tumour or neoplasm. The types are named by the tissue of origin: carcinoma in epithelial cells, sarcoma in connective tissue, leukemia in blood forming tissue and lymphoma in the lymph nodes and spleen. Malignant tumours spread to other parts of the body, a process called metastasis, whereas benign tumours do not. Cancer causing agents are called carcinogens, and because cancer cells divide rapidly they are more easily damaged by radiation than normal cells.

Diabetes mellitus

Diabetes mellitus is a chronic metabolic disorder characterised by increased blood glucose. It arises from insufficient or deficient insulin secretion, failure of secretion, or resistance to insulin. Its classic symptoms carry their own names: polyphagia for excessive hunger, polydipsia for excessive thirst and polyuria for excessive urination.

Obesity and coronary heart disease

Obesity is the state in which excess body fat accumulates and body weight increases abnormally. Coronary heart disease is the most common form of heart disease and is caused by the deposition of cholesterol in the blood vessels, which leaves the heart muscle with an insufficient blood supply.

AIDS and awareness

AIDS is caused by the Human immunodeficiency virus, which attacks the immune system. The chapter notes that much ignorance surrounds the disease, and that the National AIDS Control Organization together with non governmental organisations works to educate people. The first of December is observed each year as World AIDS Day.

Common mistakes to avoid

• Saying alcohol acts first on the liver. It acts immediately on the central nervous system; liver damage builds up later.
• Confusing carcinoma with sarcoma. Carcinoma is epithelial, sarcoma is connective tissue.
• Associating metastasis with benign tumours. Only malignant tumours spread.
• Mixing up polyphagia and polydipsia. Polyphagia is excessive hunger, polydipsia is excessive thirst.
• Thinking cancer cells resist radiation. They divide rapidly, which makes them more easily damaged by it.

Test yourself on these with the practice test, then check the worked reasoning in the solved MCQs.

Frequently asked questions

What is drug addiction?

Drug addiction, also called drug abuse, is the use of certain drugs by an individual as a regular habit. It is different from taking a drug under medical direction, because the substance is used repeatedly for its effect rather than to treat a condition, and the body becomes dependent on it.

Which component of tobacco stimulates adrenaline secretion?

Nicotine is the component of tobacco responsible. It stimulates the adrenal gland to secrete adrenaline, which raises heart rate and blood pressure. Tobacco itself is used in three ways, namely smoking, chewing and snuffing, and inhaling the smoke of burning tobacco is what is called smoking.

How does alcohol affect the body immediately and in the long term?

Immediately after drinking, alcohol acts on the central nervous system, depressing it by behaving as a sedative and analgesic substance. Over a prolonged period it causes fatty liver, which develops into cirrhosis. Examination questions often ask specifically which effect comes first, so the two must be kept separate.

What are the four main types of cancer?

They are named by the tissue in which they arise. Carcinoma arises in epithelial cells, sarcoma in connective tissue, leukemia in blood forming tissue and is commonly called blood cancer, and lymphoma affects the lymph nodes and the spleen. Matching each type to its tissue is the most direct way to answer these questions.

What is metastasis?

Metastasis is the spread of cancer cells from the original tumour to other parts of the body. It is associated only with malignant tumours. A benign tumour remains confined to the place where it began and does not spread, which is the main distinction between the two.

Why are cancer cells more easily damaged by radiation than normal cells?

Radiation does its greatest harm to cells while they are dividing. Cancer is an abnormal and uncontrolled division of cells, so cancer cells are dividing far more often than the surrounding normal cells. This is why radiation therapy can destroy a tumour while leaving healthy tissue comparatively unharmed.

What causes diabetes mellitus?

Diabetes mellitus is a chronic metabolic disorder characterised by an increased blood glucose level. It results from insufficient or deficient secretion of insulin, from failure of insulin secretion altogether, or from insulin resistance, where the body no longer responds properly to the insulin that is present.

What causes coronary heart disease?

Coronary heart disease is the most common form of heart disease and is caused by the deposition of cholesterol in the blood vessels. As the vessels narrow, the heart muscle receives an insufficient supply of blood. Diet and lifestyle changes are therefore central to preventing it.