Railway Science (Biology – Miscellaneous)

Mosquito life cycle - Egg: Female mosquitoes lay their eggs on or near water bodies. Larva: Once the eggs are in water, they hatch into larvae, also known as wigglers.
Pupa: The larvae go through several molts and eventually transform into pupae, which are also called tumblers.
Imago: After a few days, adult mosquitoes emerge from the pupae. The imago stage refers to the fully developed adult mosquito that can fly and reproduce.

Nematodes possess digestive, excretory, nervous and reproductive systems. Nematodes (roundworms) are cylindrical non-segmented organisms Which infect the root stem, leaf, flower and seed of plants by entering the roots of plants from the soil. Examples of Nematodes that commonly spread disease in Humans: Ascarids, Filariasis, hookworms, pinworms.

The Magnetism present in the brain of a human is used to obtain the images of internal parts of the brain by using a technique known as MRI (Magnetic Resonance Imaging). An electrocardiogram (ECG) is a test that records the electrical activity of the heart.

Yeast is an excellent source of protein and vitamins especially B-complex vitamins. It is an eukaryotic, single-celled microorganism classified as a member of the kingdom Fungi. It is also known as riboflavin (Vitamin B2) and invertase. Vitamin A (Retinol), Vitamin C (Ascorbic acid), Vitamin K (Phylloquinone).

Penicillium: It secretes an antibiotic called penicillin (which kills and inhibits the growth of bacteria). Penicillin was first discovered in 1928 by Alexander Flemming. Fungi are eukaryotic organisms that include microorganisms such as yeasts, moulds and mushrooms. Bacteria are small single-celled organisms. Examples - E. coli, Bacillus, Pseudomonas, Streptococcus.

It is a genetically modified variety of cotton that is resistant to pests, such as lepidopterans, dipterans and coleopterans. The name 'Bt' in 'Bt cotton' is derived from a bacterium called Bacillus thuringiensis from which a resistance gene was taken and introduced into cotton.
Genetic Modification (GM) involves altering the genes of an organism, be it a plant, animal or microorganism. It is widely used to make crops resistant to certain pests and disease and improve nutrition value in a crop.

Cinchona - A genus of flowering plants in the family Rubiaceae containing at least 23 species of trees and shrubs. Malaria has been treated with Quinine, Chloroquine, Amodiaquine, Mefloquine, and Artemisinin derivatives. Malaria - Caused by the Plasmodium parasite (Falciparum, Vivax, Malariae, Ovale curtisi, Knowlesi). It is spread when an infected Anopheles mosquito bites a person.

They are destructive pests. They eat wood and other organic materials, and they can cause significant damage to buildings and other structures. Examples of beneficial insects are - Assassin bugs, Damsel bugs, Earwigs, Green lacewings, Ichneumon wasps, Minute pirate bugs, Fireflies, Soldier beetles. Silk moths produce silk, which is used to make fabric. Lac insects are used to make varnish and other products. Honey bees produce honey, which is a food source and has medicinal properties.

Lactose (C₁₂H₂₂O₁₁) - It is a disaccharide sugar containing glucose and galactose units. It makes up around 2 - 8% of milk.
Gluten - A protein (made up of two proteins - gliadin and glutenin) found in some grains (wheat, barley, and rye).
Fructose (C₆H₁₂O₆) - A monosaccharide sugar (fruit sugar).
Sucrose (C₁₂ H₂₂ O₁₁) - A disaccharide sugar composed of glucose and fructose subunits.

Macula (Yellow spot) is present near the center of the retina. It is approximately 5.5 mm in diameter. It is specialized for seeing things with visual acuity (highest clearness).