General Science Questions (MCQs) for Competitive Examinations

Notes:
The color of normal urine is usually light yellow to amber. Generally, the greater the solute volume the deeper the color. The yellow color of urine is due to the presence of a yellow pigment, urochrome. Deviations from normal color can be caused by certain drugs and various vegetables such as carrots, beets, and rhubarb.

Notes:
The veins are the vascular tissue of the leaf and are located in the spongy layer of the mesophyll. The veins are made up of: Xylem: tubes that bring water and minerals from the roots into the leaf; and Phloem: tubes that usually move sap, with dissolved sucrose, produced by photosynthesis in the leaf, out of the leaf. Veins lend support to the leaf tissue, helping it keep its shape.

Notes:
Glucose (C6H12O6), also called dextrose, is one of a group of carbohydrates known as simple sugars (monosaccharides). It is found in fruits and honey and is the major free sugar circulating in the blood of higher animals. It is the most important source of energy for cellular respiration. Glucose is stored as a polymer, in plants as starch and in animals as glycogen.

Notes:
Chlorophyll was first isolated and named by Joseph Bienaimé Caventou and Pierre Joseph Pelletier in 1817. It is a chemical found in the chloroplasts of plants that allows the plant to absorb light. Energy from the light is used in photosynthesis to make glucose.

Notes:
Keratin is a family of fibrous structural proteins that is the key structural material making up hair, horns, claws, hooves, and the outer layer of human skin. Keratin is also the protein that protects epithelial cells from damage or stress. Some keratins have also been found to regulate key cellular activities, such as cell growth and protein synthesis.

Notes:
Photosynthesis is the process of converting light energy to chemical energy and storing it in the bonds of carbohydrates (sugar). The main product of photosynthesis is glucose, which is the molecule that produces energy to run the processes of the cell. Oxygen is mainly a byproduct of the process of photosynthesis.
6H2O (water) + 6CO2 (carbon dioxide) = C6H12O6 (glucose) + 6O2 (oxygen)

Notes:
Swine influenza, also called pig influenza, swine flu, hog flu and pig flu, is an infection caused by any one of several types of swine influenza viruses. Swine flu, also known as the H1N1 virus, is a relatively new strain of an influenza virus that causes symptoms similar to the regular flu. It originated in pigs, but is now known to spread primarily from person to person.

Notes:
The nephron is the basic structural and functional unit of the kidney. Its chief function is to regulate the concentration of water and soluble substances like sodium salts by filtering the blood, reabsorbing what is needed and excreting the rest as urine.

Notes:
Apiculture is the practice of keeping bees as well as the manufacturing of honey and beeswax. A beekeeper (or apiarist) keeps bees in order to collect their honey and other products that the hive produce to pollinate crops, or to produce bees for sale to other beekeepers. A location where bees are kept is called an apiary or “bee yard.”

Notes:
Interbreeding destroys the genetic integrity of a species, causing it to become progressively infertile or extinct, evolutionary changes in anatomy and biology developed to prevent interbreeding between species. The specific term is Reproductive Isolation, which acts to prevent some, any, or all stages of reproduction from occurring. Reproductive Isolation is very important in keeping animal species separated.