Sample AFMC Biology Mock Test

Rennin belongs to the class of pepsin and trypsin. All these enzymes act on proteins during the process of digestion. 

It is a large multi-branched polymer of glucose which is accumulated in response to insulin and broken down into glucose in response to glucagon. Glycogen is mainly stored in the liver and the muscles and provides the body with a readily available source of energy if blood glucose levels decrease.

The cystic duct connects the top of the gallbladder’s neck to the common hepatic duct. It then joins the common bile duct, which meets pancreatic duct before it empties into the duodenum. In the average adult, the cystic duct measures four centimeters in length.

The chief cells in the stomach secrete pepsinogen which activates to form pepsin. The precursor of pepsin, pepsinogen is secreted by the Chief Cells of the Stomach wall. Pepsinogen is converted to pepsin under the effect of gastric juices and hydrochloric acid. Pepsin is secreted by the Zymogen cells of the stomach.

People with type A blood have the antigen A on the surface of their RBCs, while people with type B blood have the B antigen. Individuals with type AB blood have both A and B antigens, whereas people with type O blood have no antigens present (there is no antigen O). The antibody that reacts against antigen A is called anti-A, and is found in the plasma of people who do not possess antigen A on their own RBCs – that is, people with type O or type B blood. The antibody that reacts against antigen B is called anti-B and is present in those who do not possess antigen B in their RBCs – people with type O or type A blood.

Variation appear during meiosis due to independent assortment and crossing over because both process formation of a new gene combination or heterogygous zygote.

Beri- beri is caused by the deficiency of vitamin- B1 (thiamine). Vitamin-K is also known as antihaemorrhagic factor. The main sources of vitamin-K are green leafy vegetables such as cauliflower, cabbage, spinach, etc. It is also found in animal sources like egg yolk, liver, etc. Vitamin-K is essential for blood clotting and deficiency of it causes haemorrhage.

Riboflavin (Vitamin B₂) is the precursor of two coenzymes known as flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). Both are essential for tissue respiration and the generation of energy from the metabolism of carbohydrates, amino acids and fats.

Basophils are circulating granulocytes that respond to allergic stimuli by migrating and accumulating at sites of allergic inflammation.They contain cytoplasmic granules with similar histamine levels per cell as mast cells. In contrast, the amount of tryptase in basophils is less than 1% of that in mast cells.

Neutrophils are the most abundant white blood cell in humans and arise from granulocytes. They are also phagocytic in nature, and Metchnikoff called neutrophils the “archetypal phagocyte”.Neutrophils are the first immune cells to be recruited, which can be through the cytokines produced by macrophages.

A Svedberg unit (symbol S, sometimes Sv) is a non-metric unit for sedimentation coefficient. The Svedberg unit (S) offers a measure of a particle's size based on its sedimentation rate, i.e. how fast a particle of given size and shape 'settles' to the bottom of a solution.

Testosterone is responsible for the development of secondary sex characteristics, features that stimulate male development (including characteristics that are not part of the reproductive system, such as facial hair growth and voice change).

A pacemaker is a medical device that generates electrical impulses delivered by electrodes to contract the heart muscles and regulate the electrical conduction system of the heart.

Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It is the inactive form and most of it is converted to an active form called triiodothyronine by organs such as the liver and kidneys. Thyroid hormones play vital roles in regulating the body’s metabolic rate, heart and digestive functions, muscle control, brain development and maintenance of bones.

Prothrombin is a protein made by the liver. Prothrombin helps blood to make normal clots. The "prothrombin time" is one way of measuring how long it takes blood to form a clot, and it is measured in seconds (such as 13.2 seconds). A normal PT indicates that a normal amount of blood-clotting protein is available.

Kala azar is caused by bites from female phlebotomine sandflies – the vector (or transmitter) of the leishmania parasite. The sand flies feed on animals and humans for blood, which they need for developing their eggs. If blood containing leishmania parasites is drawn from an animal or human, the next person to receive a bite will then become infected and develop leishmaniasis. Months after this initial infection the disease can progress into a more severe form, called visceral leishmaniasis or, kala azar. Initially, leishmania parasites cause skin sores or ulcers at the site of sand fly bites. If the disease progresses, it attacks the immune system. Kala azar presents after two to eight months, with more generalised symptoms including prolonged fever and weakness.

Cryopreservation:Cryopreservation [preservation in the frozen state (cryo means extreme cold, derived from Latin word kruos = ‘frost’)] is based on the reduction and subsequent arrest of metabolic functions of biological material by imposition of ultra-low temperature.

Cholera is caused by bacteria called Vibrio cholerae. The disease’s deadly effects are the result of a strong toxin known as CTX that is produced by these bacteria in your small intestine. CTX interferes with the normal flow of sodium and chloride when it binds to your intestinal walls. When the bacteria attaches to the small intestine’s walls, your body begins to secrete large amounts of water that lead to diarrhea and rapid loss of fluids and salts.

The two genes that produce red and green light-sensitive proteins are located on the X chromosome. Mutations in these genes can cause color blindness. Color blindness is a common inherited sex-linked disorder that affects a person's ability to see or recognize certain colors.

genetic red–green color blindness affects males much more often than females, because the genes for the red and green color receptors are located on the X chromosome, of which males have only one and females have two.

Heroine like opium and morphine is obtained from the resin of poppy plant i.e papaver somniferum. This belongs to family papaveraceae.

Afforestation is the establishment of a forest or stand of trees (forestation) in an area where there was no previous tree cover.
Many government and non-governmental organizations directly engage in programs of afforestation to create forests, increase carbon capture and carbon sequestration, and help to anthropogenically improve biodiversity. In the UK, afforestation may mean converting the legal status of some land to royal forest.

By definition a true coelom is the coelom lined by mesoderm on both sides because a true coelom is produced either by splitting in the mesoderm or by fusion of mesodermally lined pouches.

Brunner's glands (or duodenal glands) are compound tubular submucosal glands found in that portion of the duodenum which is above the hepatopancreatic sphincter (a.k.a. sphincter of Oddi).

Sea snakes, venomous elapid snakes that inhabit marine environments, are the most abundant and widely dispersed group of poisonous reptiles in the world. Sea snakes are characterized by laterally compressed bodies and vertically flattened tails and nostrils with valve-like flaps, giving them an eel-like appearance.

Ascariasis can be treated by antihelminthic drugs such as Alcopar, Antipar, santonin, chenopodium oil and Tetrachloroethylene etc.

Nekton or necton refers to the aggregate of actively swimming aquatic organisms in a body of water. The term was proposed by German biologist Ernst Haeckel to differentiate between the active swimmers in a body of water, and the passive organisms that were carried along by the current, the plankton.

Krait venom is extremely neurotoxic and induces muscle paralysis,its bite is lethal to man. There are 12 Species and 5 sub-species of Krait Snakes, Some of them are the common krait, banded krait and Indian Krait. The Bungarus,commonly referred as Kraits is most dangerous venomous snake of India and one of the deadliest snakes of the world. The maximum deaths of common krait per bite is 60, It can be seen in the deep jungles of India.
 

Trochophores exist as a larval form within the trochozoan clade, which include the entoprocts, molluscs, annelids, echiurans, sipunculans and nemerteans.

Frog’s skin surface has mucous glands which makes it moist and through it moist skin it respires most of the time. So, it possess mucous glands but not sweat glands and sebaceous glands. They also possess poisonous glands to protect themselves from predators.Mammary glands are characteristic feature of mammals, whereas frogs are amphibians. So, they also do not have mammary glands.

Nephridia and setae are found in Annelids. Sea Mouse is an Annelida animal. Sea Anemone and Sea Pen belong to phyla Cnidaria and Sea Urchin is an echinoderm animal. Thus, the correct answer is option B.

Spirogyra species can reproduce both sexually and asexually. Asexual, or vegetative, reproduction occurs by simple fragmentation of the filaments. Sexual reproduction occurs by a process known as conjugation, in which cells of two filaments lying side by side are joined by outgrowths called conjugation tubes.

Arthropods are joint-legged animals and you must have come across a few of these animals. Some prominent ones include insects, spiders, ants, cockroach ,bees, crabs, shrimps, millipedes, centipedes etc. Scientifically speaking, they all come under the Animal Kingdom under phylum Arthropoda.

Because gymnosperms have no ovary, they can never produce fruit. Seeds develop from the ovules that are found in the developed ovaries or fruit, but in the case of gymnosperms, the ovules are located directly on the surface of the flower or cone. Yews and ginkgoes develop fruitlike structures, but their seed is not inside these organs, which makes them gymnosperms.

Plants require this mineral (Zn) only in traces and its higher concentrations are highly toxic.

The largest sized flower in the world is Rafflesia arnoldii which is found in Indonesia. And it is a parasitic plant which has no roots or leaves. Bcoz of that reason they use their haustoria that use to suck nutrients from the roots of other plants. So they are known as total root parasite.

Tyloses are outgrowths on parenchyma cells of xylem vessels of secondary heartwood. When the plant is stressed by drought or infection, tyloses will fall from the sides of the cells and "dam" up the vascular tissue to prevent further damage to the plant.

Martynia is a monotypic genus in the Martyniaceae family consisting of a single species, Martynia annua L., which is commonly known as cat's claw, tiger's claw, or iceplant.

In humans the membrane that covers the brain (and majority of the spinal cord) is called the meninges. It is a fibrous membrane of tissue composed of three layers, the dura mater, arachnoid mater and pia mater.

Chrysanthemum is propagated vegetatively either through root suckers or terminal cuttings. Suckers : Suckers arise from the underground stem and these are separated and planted in prepared nursery beds during January for stock plants. Regular pinching is performed in these plants for vigorous and profuse branching. Some of these stock plants are used for preparation of cuttings. The first pinching is performed in April, followed by monthly pinching upto June. After 3 pinching in June, cuttings are taken from these mother plants.

The internal ear is a delicate, irregular organ called membranous labyrinth. It is surrounded by an almost similarly shaped bony labyrinth. The membranous labyrinth is joined to the bony labyrinth at certain points, but its greater part is separated from the bony labyrinth by a narrow perilymphatic space. This space contains a watery fluid called perilymph which closely resembles cerebrospinal fluid in composition, The membranous labyrinth is itself filled with another fluid, the endolymph.

So, the correct answer is 'Endolymph'

A dorsal root ganglion also known as a posterior root ganglion, is a cluster of neurons (a ganglion) in a dorsal root of a spinal nerve. The cell bodies of sensory neurons known as first-order neurons are located in the dorsal root ganglia.

Because as we know that human have a pair of kidney and which filter our blood & removes poisonous substance from the blood. So, in that case when one kidney is removed from the body, another kidney will work and the person can survive and remain normal.

Photorespiration imposes costs on plant energy metabolism. The oxygenase reaction of RUBISCO does not result in energy or carbon gain for the plant. The ribulose-1,5-bisphosphate molecule for this reaction is therefore “wasted”. 

Reproductive isolation term given by Ernest Mayer. This collection is evolutionary mechenism and depend on behavior and physiological process. They prevent members of different species from producing progany or ensure that any offspring are sterile.

A few animals have evolved to supplement their energy needs by temporarily harboring chloroplasts, having ingested them through grazing on algae . Autotrophy does not provide enough energy to fuel the activities of animals.

A clone is a group of individuals obtained through micro propagation. Micropropagation is the growing of plants from meristematic tissue or somatic cells of superior plants on nutrient suitable media under controlled asceptic physical condition.

The ovule is part of the makeup of the female reproductive organ in seed plants. It’s the place where female reproductive cells are made and contained, and it is what eventually develops into a seed after fertilization, only for the seed to then ripen and produce a complete adult plant. Ovules are contained in ovaries at the bottom of a vase-like structure, the carpel, which has a neck called a style and an opening at the top, called a stigma. The body of these ovules becomes at a right angle in relation to the funicle, so it looks like the ovule is lying on its side.

Atropine is a non-selective muscarinic antagonist that is mainly used as an adjunct for anaesthesia. The name "belladonna" originates from the Italian words "beautiful woman" and the historical use of herb eye-drops by women to dilate the pupils of the eyes for aesthetic purposes. Belladonna is a poisonous plant and belladonna intoxication from accidental ingestion may result in a severe anticholinergic syndrome, which is associated with both central and peripheral manifestation.

Adam's Apple represents thyroid cartilage of larynx which helps to protect the frontal part of the larynx.

The Greek philosopher Aristotle (384–322 BC) was one of the earliest recorded scholars to articulate the theory of spontaneous generation, the notion that life can arise from nonliving matter. Aristotle proposed that life arose from nonliving material if the material contained pneuma (“vital heat”).