Mock Test-1 (Paper-1) (Question 51-100)

The production of naked seeds or ovules without fruits is one of the main characteristic features of Gymnosperms. Cycas sp. is a gymnosperm.
Gymnosperms

• This term is made from two greek words: gymno— means naked and sperma— means seed.
• The plants of this group bear naked seeds [ovules are not enclosed by any ovary wall] and are usually perennial, evergreen and woody. The seeds that develop post-fertilisation are naked too. Examples are pines, such as deodar.
• Gymnosperms include medium-sized trees or tall trees and shrubs. One of the gymnosperms, the giant redwood tree Seguoia is one of the tallest tree species.
• The roots are generally tap roots {Plant Parts and Their Functions}. Roots in some genera have fungal association in the form of mycorrhiza (Pinus), while in some others (Cgcas) small specialised roots called coralloid roots are associated with N2-fixing cyanobacteria.
• The leaves in gymnosperms are well-adapted to withstand extremes of temperature, humidity and wind.
• In conifers, the needle-like leaves reduce the surface area. Their thick cuticle and sunken stomata also help to reduce water loss.
• The gymnosperms are heterosporous; they produce haploid microspores and megaspores.
• The two kinds of spores are produced within sporangia that are borne on sporophylls which are arranged spirally along an axis to form lax or compact strobili or cones.

These characteristics are found in Tropical thorn forest and scrubs. Leaves are modified into spines (thorns). The stems are succulent to conserve water.

• Tropical Thorn Forests are found in Rajasthan, Punjab, Haryana, and sections of Gujarat and Madhya Pradesh.
• They are also found in the dry parts of the Deccan plateau, where annual rainfall is less than 75 cm.
• Outside India, this forest can be found in much of southwestern North America and southwestern Africa, as well as in lesser regions of Africa, South America, and Australia.

Book lungs occur in Arachnids.
Arachnid

• Arachnidais a class of joint-legged arthropods, in the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, harvestmen, camel spiders, whip spiders and vinegaroons.
• Almost all extant arachnids are terrestrial, living mainly on land. However, some inhabit freshwater environments and, with the exception of the pelagic zone, marine environments as well.
• Like all arthropods, arachnids have segmented bodies, tough exoskeletons, and jointed appendages. Most are predatory.
• Arachnids lack jaws and, with only a few exceptions, inject digestive fluids into their prey before sucking its liquefied remains into their mouths.
• Except among daddy longlegs and the mites and ticks, in which the entire body forms a single region, the arachnid body is divided into two distinct regions: the cephalothorax, or prosoma, and the abdomen, or opisthosoma. The sternites (ventral plates) of the lower surface of the body show more variation than do the tergites (dorsal plates).
• The arachnids have simple (as opposed to compound) eyes.

Bowman capsule is found in kidneys. It takes part in filtration of blood. It is a cup like structure.
Kidneys

• Kidneys are reddish brown, bean shaped structures situated between the levels of last thoracic and third lumbar vertebra close to the dorsal inner wall of the abdominal cavity.
• Each kidney of an adult human measures 10-12 cm in length, 5-7 cm in width, 2-3 cm in thickness with an average weight of 120-170 g.
• Towards the center of the inner concave surface of the kidney is a notch called hilum through which ureter, blood vessels and nerves enter.

Quinine is a natural white crystalline alkaloid obtained from the bark of Cinchona sp. of family Rubiaceae. It has antimalarial, analgesic (painkilling), and anti-inflammatory and antipyretic (fever-reducing) properties.

Camphor is a waxy, flammable, white or transparent solid with a strong aromatic odour. Cinnamomum camphora is the source of camphor. Vanilla is a flavour obtained from the orchid of the genus Vanilla, generally from Mexican Vanilla planifolia.

Chicory is a root extract or roots of Cichorium intybusis used commercially as a substitute for coffee.

Three types of cells are found in pancreas. a-cells, b-cells, d-cells. a-cells secrete peptide hormone glucagon. b-cells synthesise and secrete the endocrine hormone, insulin, the hyposecretion of which leads to abnormal metabolism of body's sugar and causes Diabetes mellitus. d-cells produce somatostatin.

Hepatitis-B is a potentially life-threatening liver infection caused by the hepatitis B virus. It can cause chronic liver disease and puts people at high risk of death from cirrhoris of liver and liver cancer.

Hepatitis-B virus is transmitted between people by contact with blood or other body fluid of an contact with the blood or other body fluid.

• Nitrolim: It is an inorganic compound which is also known as Calcium cyanamide with the formula . It is the calcium salt of the cyanamide (CN-) ion. This chemical is used as fertilizer in the agricultural industry.
• -Nitrolim is prepared by using calcium carbide. The carbide powder is heated at about 1000 in an electric furnace into which nitrogen gas is passed for many hours. The product is then cooled to ambient temperatures and any unreacted carbide is leached out with water while being cautious. The reaction for this preparation is shown below:-
  CaC2 +N2 ----- CaCN2 +C
• -lt is mainly in agriculture as a fertilizer as in contact with water, it decomposes itself and liberates ammonia which is very useful for soil and plants being grown in the fields. It was also used to produce sodium cyanide by fusing with sodium carbonate which is used in the cyanide process in gold mining. It can also be used in the formation of compounds like calcium cyanide and melamine.

Marburg virus

• It is in the same family as the virus that causes Ebola virus disease.
• Human infection with Marburg virus disease initially results from prolonged exposure to mines or caves inhabited by Rousettus bat colonies.
• Marburg can spread through human-to-human transmission via direct contact (through broken skin or mucous membranes) with the blood, secretions, organs or other bodily fluids of infected people, and with contaminated surfaces & materials.
• Two large outbreaks that occurred simultaneously in Marburg and Frankfurt in Germany, and in Belgrade, Serbia, in 1967, led to the initial recognition of the disease.
• There have been 12 major Marburg outbreaks since 1967, mostly in southern and eastern Africa.