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Part 087 – Biology Previous Year Questions

Q1. What happens to a person who receives the wrong type of blood?
(a) All the arteries constrict
(b) All the arteries dialates
(c) The RBCs agglutinate
(d) The spleen and lymphnodes deteriorate
Ans: (c) Red blood cell agglutination indicates clumping of RBC’s due to cold agglutinins which are most commonly IgM antibodies. These antibodies crosslink red cells, which causes overlapping (arrow) and loss of central pallor. The agglutination leads to reduction in red cell count, elevation in MCH and MCV as measured by automated instruments. Hemagglu-tination is when the particles involved are red blood cells. The agglutin is called hemagglutinin. In cross-matching, agglutination occurring when donor red blood cells and recipient’s serum or plasma are incubated together indicates that the donor blood is incompatible for that particular recipient.

Q2. Ringworm is a ……. disease.

(a) Bacterial (b) Protozoan
(c) Viral (d) Fungal
Ans: (d) Dermatophytosis or ringworm is a clinical condition caused by fungal infection of the skin in humans, pets such as cats, and domesticated animals such as sheep and cattle. The term “ringworm” is a misnomer, since the condition is caused by fungi of several different species and not by parasitic worms. The fungi that cause parasitic infection (dermatophytes) feed on keratin, the material found in the outer layer of skin, hair, and nails. These fungi thrive on skin that is warm and moist, but may also survive directly on the outsides of hair shafts or in their interiors. In pets, the fungus responsible for the disease survives in skin and on the outer surface of hairs.

Q3. Pituitary gland is situated in

(a) the base of the heart
(b) the base of the brain
(c) the neck
(d) the abdomen
Ans: (b) Pituitary gland or hypophysis, is an endocrine gland about the size of a pea and weighing 0.5 grams (0.018 oz) in humans. It is not a part of the brain. It is a protrusion off the bottom of the hypothalamus at the base of the brain, and rests in a small, bony cavity (sella turcica) covered by a dural fold (diaphragma sellae). The pituitary is functionally connected to the hypothalamus by the median eminence via a small tube called the infundibular stem (Pituitary stalk). The pituitary fossa, in which the pituitary gland sits, is situated in the sphenoid bone in the middle cranial fossa at the base of the brain. The pituitary gland secretes nine hormones that regulate homeostasis.

Q4. From which part of the plant is clove, the commonly used spice, obtained ?

(a) Fruit (b) Flower bud
(c) Stem (d) Root
Ans: (b) Cloves are the aromatic dried flower buds of a tree in the family Myrtaceae, Syzygium aromaticum. The clove tree is an evergreen that grows to a height ranging from 8–12 m, having large leaves and sanguine flowers in numerous groups of terminal clusters. The flower buds are at first of a pale color and gradually become green, after which they develop into a bright red, when they are ready for collecting. Cloves are harvested when 1.5–2 cm long, and consist of a long calyx, terminating in four spreading sepals, and four unopened petals which form a small ball in the centre.

Q5. Chewing gum is made from

(a) Resin (b) Tannin
(c) Latex (d) Gum
Ans: (c) Chewing gum is a type of gum made of chicle, a natural latex product, or synthetic rubber known as polyisobutylene. Most chewing gums are considered polymers. Sugar-free gum sweetened with xylitol has been shown to reduce cavities and plaque. The sweetener sorbitol has the same benefit, but is only about one-third as effective as xylitol. Xylitol is specific in its inhibition of Streptococcus mutans, bacteria that are significant contributors to tooth decay.

Q6. The brain of human adult weighs about

(a) 1200 – 1300 gm
(b) 1600 – 2000 gm
(c) 500 – 800 gm
(d) 100 – 200 gm
Ans: (a) The adult human brain weighs on average about 3 lbs. (1.5 kg) with a volume of around 1130 cubic centimetres (cm3) in women and 1260 cm3 in men, although there is substantial individual variation. Men with the same body height and body surface area as women have on average 100g heavier brains, although these differences do not correlate in any simple way with IQ or other measures of cognitive performance. The human brain has the same general structure as the brains of other mammals, but is larger than any other in relation to body size. Large animals such as whales and elephants have larger brains in absolute terms, but when measured using the encephalization quotient which compensates for body size, the human brain is almost twice as large as the brain of the bottlenose dolphin, and three times as large as the brain of a chimpanzee. Much of the expansion comes from the part of the brain called the cerebral cortex, especially the frontal lobes, which are associated with executive functions such as self-control, planning, reasoning, and abstract thought.

Q7. Total number of bones in man is

(a) 206 (b) 266
(c) 300 (d) 306
Ans: (a) A typical adult human skeleton consists of 206 bones. The 206 bones of the skeleton provide a framework and points of attachment for many of the soft tissues of the body. The number of bones changes with age, as multiple ossific nuclei joined by synchondroses fuse into fewer mature bones, a process which typically reaches completion in the third decade of life.

Q8. Which of the following snakes killed for its beautiful skin has been declared an endangered species ?

(a) Python
(b) King Cobra
(c) Russel’s Viper
(d) Krait
Ans: (c) Russell’s Vipers are highly venomous terrestrial snakes found in India which are known for their dark brown spots and lustrous skin. Russell’s Vipers are protected under the schedule II of Wildlife Protection Act. Russell’s Vipers, although belong to the class reptilila of vertebrates, give birth to young ones instead of laying eggs. Primarily nocturnal in nature, the snake is often responsible for the majority of snakebite incidents.

Q9. The colour of the eye depends upon the pigment present in

(a) cornea (b) iris
(c) rods (d) cones
Ans: (b) Eye colour is a polygenic phenotypic character determined by 2 distinct factors: the pigmentation of the eye’s iris and the frequency-dependence of the scattering of light by the turbid medium in the stroma of the iris. In humans, the pigmentation of the iris varies from light brown to black, depending on the concentration of melanin in the iris pigment epithelium (located on the back of the iris), the melanin content within the iris stroma (located at the front of the iris), and the cellular density of the stroma.

Q10. The ability of the eye to see in the dark, is due to the production of a purple pigment known as

(a) Carotene (b) Rhodopsin
(c) Iodopsin (d) Retinene
Ans: (d) Retinene–1 is better known as retinaldehyde or simply retinal and is fundamental in the transduction of light into visual signals in the photoreceptor level of the retina (known as the visual cycle). Retinene–2 is more formally known as dehydroretinaldehyde. The energy of impinging photons will convert retinaldehyde from an 11-cis isomer into an all-trans form. In the retina, this conversion induces a conformational change in the surrounding photopsin protein pigment, leading to signaling through the G protein transducin. Retinaldehyde also forms a part of bacteriorhodopsin, a light-induced proton pump found in some archaea.

Q11. Which of the following statements is true ?

(a) Dehusked cereals and pulses are more nutritious
(b) Whole grain cereals and pulses are more nutritious
(c) Processed cereal products are nutrient dense
(d) Breakfast cereals are nutrient dense
Ans: (b) Cereal and pulse crops are staple foods that provide essential nutrients to many populations of the world. Traditionally, whole grains were consumed but most current foods are derived from refined fractions of cereal and pulse crops. Consumption of processed or refined products may reduce the health benefits of food. In wheat-based processed foods, for example, the removed 40% of the grain (mainly the bran and the germ of the wheat grain) contains the majority of the health beneficial components. These components, particularly non-essential phytoche-micals such as carotenoids, polyphenols, phytosterols/ stanols, and dietary fibers, have been shown to reduce the risk of major chronic diseases of humans, such as cancer, cardiovascular diseases, and Parkinson’s disease. Such bioactives are therefore good candidates for ingredients of nutraceuticals and functional foods.

Q12. The vitamin most readily destroyed by heat is

(a) Riboflavin
(b) Ascorbic acid
(c) Tocopherol
(d) Thiamine
Ans: (b) Vitamin C (Ascorbic Acid) is the most easily destroyed vitamin. It is destroyed by oxygen, heat (above 70 degrees) and it leaks out into the cooking water because it is a water soluble vitamin. To preserve vitamin C in food, citrus fruits, tomatoes, juices, broccoli, green peppers, cantaloupe and strawberries should be stored in the refrigerator uncut until we need them. Steaming and stir-frying are two methods that help conserve vitamin C content.

Q13. Which one of the following is not a vaccine ?

(a) BCG
(b) Anti-rabies
(c) Polio vaccine
(d) Progesterone
Ans: (d) Progesterone is one of the hormones in our bodies that stimulates and regulates various functions. Progesterone plays a role in maintaining pregnancy. The hormone is produced in the ovaries, the placenta (when a woman gets pregnant) and the adrenal glands. It helps prepare your body for conception and pregnancy and regulates the monthly menstrual cycle. It also plays a role in sexual desire.

Q14. The disease that is caused by virus is

(a) Typhoid (b) Cholera
(c) Common Cold (d) Tetanus
Ans: (c) Common cold is a viral infectious disease of the upper respiratory tract which affects primarily the nose. Symptoms include coughing, sore throat, runny nose, and fever which usually resolve in seven to ten days, with some symptoms lasting up to three weeks. Well over 200 viruses are implicated in the cause of the common cold; the rhinoviruses are the most common. It is the most frequent infectious disease in humans with the average adult contracting two to three colds a year and the average child contracting between six and twelve.

Q15. The locomotory organ of ‘Amoeba’ is

(a) Pseudopodia
(b) Parapodia
(c) Flagella (d) Cilia
Ans: (a) Pseudopods or pseudopodia (singular: pseudopodium) are temporary projections of eukaryotic cells. Cells that possess this faculty are generally referred to as amoeboids. Pseudopodia extend and contract by the reversible assembly of actin subunits into microfilaments. Filaments near the cell’s end interact with myosin which causes contraction. The pseudopodium extends itself until the actin reassembles itself into a network. This is how amoebas move, as well as some cells found in animals, such as white blood cells. They are most commonly found on eubacteria.

Q16. The number of chromosomes present in normal human being are

(a) 23 (b) 46
(c) 22 (d) 48
Ans: (b) A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions. Chromosomes in humans can be divided into two types: autosomes and sex chromosomes. Certain genetic traits are linked to a person’s sex and are passed on through the sex chromosomes. The autosomes contain the rest of the genetic hereditary information. All act in the same way during cell division. Human cells have 23 pairs of chromosomes (22 pairs of autosomes and one pair of sex chromosomes), giving a total of 46 per cell.

Q17. An instrument for measuring blood pressure is called

(a) Barometer
(b) Spirometer
(c) Sphygmomanometer
(d) Haemocytometer
Ans: (c) A sphygmomanometer or blood pressure meter is a device used to measure blood pressure, composed of an inflatable cuff to restrict blood flow, and a mercury or mechanical manometer to measure the pressure. It is always used in conjunction with a means to determine at what pressure blood flow is just starting, and at what pressure it is unimpeded. Manual sphygmomanometers are used in conjunction with a stethoscope. The device was invented by Samuel Siegfried Karl Ritter von Basch in 1881. Scipione Riva-Rocci introduced a more easily used version in 1896. In 1901, Harvey Cushing modernized the device and popularized it within the medical community.

Q18. The term ‘Rh factor’ refers to

(a) Rhesus factor
(b) Rheumatoid factor
(c) Renal factor
(d) Rhombic factor
Ans: (a) Each person’s blood is one of four major types: A, B, AB, or O. Blood types are determined by the types of antigens on the blood cells. Antigens are proteins on the surface of blood cells that can cause a response from the immune system. The Rh factor (Rhesus factor) is a type of protein on the surface of red blood cells. Most people who have the Rh factor are Rhpositive. Those who do not have the Rh factor are Rh-negative. In contrast to the ABO blood group, immunization against Rh can generally only occur through blood transfusion or placental exposure during pregnancy in women.

Q19. The discoverer of pencillin was

(a) Lord Lister
(b) Alexander Fleming
(c) Karl Landsteiner
(d) Walter Reed
Ans: (b) Penicillin is one of the earliest discovered and widely used antibiotic agents, derived from the Penicillium mold. Antibiotics are natural substances that are released by bacteria and fungi into their environment, as a means of inhibiting other organisms. In 1928, Sir Alexander Fleming observed that colonies of the bacterium Staphylococcus aureus could be destroyed by the mold Penicillium notatum, proving that there was an antibacterial agent there in principle. This principle later lead to medicines that could kill certain types of disease-causing bacteria inside the body.

Q20. Blood groups were discovered by

(a) Altmann
(b) Landsteiner
(c) Losch
(d) Ronald Ross
Ans: (b) Karl Landsteiner was an Austrian biologist and physician. He is noted for having first distinguished the main blood groups in 1900, having developed the modern system of classification of blood groups from his identification of the presence of agglutinins in the blood, and having identified, with Alexander S. Wiener, the Rhesus factor, in 1937, thus enabling physicians to transfuse blood without endangering the patient’s life. With Constantin Levaditi and Erwin Popper, he discovered the polio virus, in 1909. In 1930 he received the Nobel Prize in Physiology or Medicine. He was awarded a Lasker Award in 1946 posthumously and is recognised as the father of transfusion medicine.

Q21. The animal which can tolerate more summer heat is

(a) Buffalo (b) Cow
(c) Goat (d) Donkey
Ans: (c) Some livestock (and people) tolerate heat better than others. Sheep and goats tend to be less susceptible to heat stress than swine, cattle, llamas, and alpacas. Hair sheep usually tolerate heat better than wooled sheep. This is why they are often used for training and trialing herding dogs. Fat-tailed sheep are also more heat tolerant. The European sheep breeds are usually the least heat-adaptive because they tend to have shorter bodies and legs, short, thick ears, tight skin, and dense fleeces. Goats tend to tolerate heat better than sheep. Goats with loose skin and floppy ears may be more heat tolerant than other goats.

Q22. According to Darwin’s Theory of Evolution, long necks in giraffes

(a) arose because of constant attempt to reach leaves on tall trees, generation after generation
(b) do not give them any special advantage and is just an accident
(c) give them advantage in finding food, because of which those with long necks survive
(d) is a result of the special weather prevalent in African Savannah
Ans: (a) Darwin was the first to propose that long necks evolved in giraffes because they enabled the animals to eat foliage beyond the reach of shorter browsers. Darwin himself wrote ‘…it seems to me almost certain that an ordinary hoofed quadruped might be converted into a giraffe.’ He speculated that fourlegged animals with longer and longer necks would be capable of reaching higher leaves and vegetation. Thus, during droughts, they would be more likely to survive and pass on this characteristic, than those with shorter necks. Over time, a creature that was not a giraffe would evolve into a giraffe with an extraordinarily long neck.

Q23. Rickets is the deficiency disease of Vitamin D, in which the affected part is the

(a) skin (b) hair
(c) bone (d) blood
Ans: (c) Rickets is a softening of bones in children due to deficiency or impaired metabolism of vitamin D, phosphorus or calcium, potentially leading to fractures and deformity. Rickets is among the most frequent childhood diseases in many developing countries. The predominant cause is a vitamin D deficiency, but lack of adequate calcium in the diet may also lead to rickets (cases of severe diarrhea and vomiting may be the cause of the deficiency). Although it can occur in adults, the majority of cases occur in children suffering from severe malnutrition, usually resulting from famine or starvation during the early stages of childhood.

Q24. ‘Darwin finches’ refers to a group of

(a) Fishes (b) Lizards
(c) Birds (d) Amphibians
Ans: (c) Darwin’s finches (also known as the Galápagos finches) are a group of about 15 species of passerine birds. They often are classified as the subfamily Geospizinae or tribe Geospizini. It is still not clear which bird family they belong to, but they are not related to the true finches. They were first collected by Charles Darwin on the Galápagos Islands during the second voyage of the Beagle. All are found only on the Galápagos Islands, except the Cocos Island Finch from Cocos Island.

Q25. The dried flower buds are used as a spice in

(a) Cardamom (b) Cinnamon
(c) Cloves (c) Saffron
Ans: (c) Cloves are the dried flower buds of an evergreen tree native to eastern Indonesia. Cloves are a versatile spice that can be used in drinks and in both sweet and savoury dishes.

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