General Science Questions (MCQs) for Competitive Examinations

Notes:
In the blood the key minerals are iron, copper, zinc, sodium, potassium, calcium and magnesium. Minerals constitute important part of blood plasma that constitutes almost 55% of blood. In the blood, iron is found in larger amounts than any other mineral.

Notes:
New born babies and children normally breathe faster than older children and adults. Their respiratory rate is about 30-60 breaths per minute. The respiratory rate for the different age-categories of children is:-6-12 months: 24-30; 1-5 years: 20-30; 6-12 years: 12-20.

Notes:
The bark of the common Willow tree is the source of a wide range of phenolic glycosides, of which the most important is salicin. Salicin is metabolized into salicylic acid in the human body, and is a precursor of aspirin. It is used as a fever reducer, a mild pain reliever, and an anti-inflammatory.

Notes:
The average heart rate for adult humans is about 70 to 75 beats per minute in a normal relaxed mode. While we tend to think of the “normal” heart beat rate as being “72 beats per minute”, in actuality the heart beat rate is not and could never be constant.

Notes:
Hepatitis A vaccine (Havrix, Vaqta) is used to prevent hepatitis A, a type of liver disease that is caused by the hepatitis A virus. Hepatitis B vaccines (Recombivax HB, Engerix-B) are used to prevent hepatitis B infection, a serious liver infection caused by the hepatitis B virus (HBV). Hepatitis B is easily spread through contact with blood or other fluids of an infected person. Hepatitis D is a liver disease in both acute and chronic forms caused by the hepatitis D virus (HDV). A vaccine against hepatitis B is the only method to prevent HDV infection. No vaccine is currently available for Hepatitis C virus (HCV).

Notes:
The vascular tissue system consists of the complex tissues, xylem and phloem, which constitute discrete conducting strands called vascular bundles. Gymnosperms are the vascular plants where seeds are not enclosed within an ovary (opposite to an angiosperm or flowering plants where seeds are enclosed by mature ovaries or fruits). Collateral vascular bundle is the most common type of vascular bundle in the stems and leaves of angiosperms and gymnosperms. Here xylem and phloem remain side by side arranged on the same radius.

Notes:
Lipids are a group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides, diglycerides, triglycerides, phospholipids, and others. They encompass molecules such as fatty acids and their derivatives (including tri-, di-, monoglycerides, and phospholipids), as well as other sterolcontaining metabolites such as cholesterol.

Notes:
Cauliflowers are characterized mainly by a inflorescence composed of numerous undeveloped flowers that gather around a central axis. Cauliflower and broccoli are grown for their large, edible, very young inflorescence.

Notes:
Jonas Edward Salk was an American medical researcher and virologist, best known for his discovery and development of the first polio vaccine. by Salk and his research team was the most elaborate program of its kind in history, involving 20,000 physicians and public health officers, 64,000 school personnel, and 220,000 volunteers,” with over 1,800,000 school children participating in the trial. On April 12, 1955, Dr. Thomas Francis, Jr., of the University of Michigan, the monitor of the test results, “declared the vaccine to be safe and effective.”

Notes:
In an autosomal dominant disorder, the mutated gene is a dominant gene located on one of the nonsex chromosomes (autosomes). The early-onset form of Alzheimer disease is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person inherits the altered gene from one affected parent.