Biology MCQs

Notes:
A molecule that contains nitrogen and has the chemical properties of a base is called a Nitrogenous base. Nucleic acids are composed of a combination of 5 nitrogenous bases:
1. Guanine and adenine are double-ringed purine molecules.
2. Cytosine, thymine, and uracil are single-ringed pyrimidine molecules.

Notes:
The Bacillus Calmette–Guérin (BCG) vaccine is used to prevent tuberculosis (TB). The BCG vaccine is named after Dr Albert Calmette and Dr Camille Guerin, who developed the vaccine from a germ called Mycobacterium bovis, which is similar to TB. BCG is a live vaccine that has been processed so that it is not harmful to humans. Tuberculosis is an infectious disease caused by bacteria that affects the lungs, and sometimes other parts of the body.

Notes:
According to the American Heart Association (AHA), normal blood pressure is a systolic pressure of less than 120 millimeter of mercury (mm Hg) and a diastolic pressure of less than 80 mm Hg, or 120/80 mm Hg. Having a blood pressure greater than 140/ 90 mm Hg is considered high blood pressure or hypertension.

Notes:
Heart rate is controlled by the two branches of the autonomic (involuntary) nervous system. The sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). The sympathetic nervous system (SNS) releases the hormones (catecholamine – epinephrine) to accelerate the heart rate. The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate.

Notes:
Cabbages have no need to store food as they are seasonal plants and die after about 4 to 6 months. They do however produce food in the leaves of the plants and would utilize short-term storage (in the leaves) for simple metabolic processes.

Notes:
The blood sugar concentration or blood glucose level is the amount of glucose (sugar) present in the blood of a human or animal. The body naturally tightly regulates blood glucose levels as a part of metabolic homeostasis. The mean normal blood glucose level in humans is about 4 mM (4 m mol/L or 72 mg/dL, i.e. milligrams/decilitre); however, this level fluctuates throughout the day.

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:
Animal and vegetable fats serve as a concentrated energy source and are the highest energy sources in feedstuffs. Dietary fats and oils are a concentrated source of energy when compared to carbohydrate and protein, having over twice the amount of calories per gram.  Fats contain 2.25 times the calories per gram than protein or carbohydrates. Fats contain 9 calories/gm while protein and carbohydrates contain 4 calories per gram.

Notes:
A normal adult mouth has 32 teeth, which (except for wisdom teeth) have erupted by about age 13. The canines are situated at the ‘corners’ of the dental arches. They have a sharp, pointed biting surface. Their function is to grip and tear food. There are four canine teeth in both primary and permanent dentitions.

Notes:
Calciferol (Vitamin D); Tocopherols and tocotrienols (Vitamin E); Phylloquinone, menaquinones (Vitamin K); and Retinol, retinal, and four carotenoids including beta carotene (Vitamin A) are all fat soluble vitamins. Out of total of 64 codons are nonsense codon. They do not code for any amina acid.