Zoology (UP CPMT - 2004)

Chloragogen cells in annelids function as a liver in vertebrates. These cells store glycogen and neutralise toxins and are yellowish in colour.

Merozoites exit the liver cells and re-enter the bloodstream and begin a cycle of invasion of red blood cells, known as asexual replication. In red blood cells, they develop into mature schizonts, which rupture, releasing newly formed merozoites. These merozoites then reinvade other red blood cells. It causes fever in malaria.

Glycolysis is the first step in the breakdown of glucose for extracting energy for cellular metabolism. Most living organisms carry out glycolysis as a part of their metabolism. The process does not use oxygen and can also take place under anaerobic conditions. It occurs in cytoplasm.

Collagen is the main structural protein in the extracellular space of various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals and makes up to 25% to 35% of the whole-body protein content.

The reaction catalysed by arginase enzyme is: Arginine + H₂O → Ornithine + Urea. It is the final enzyme of the urea cycle.

Adaptive radiation is a process in which organisms diversify rapidly from an ancestral founder species into a multitude of new forms, particularly when a change in the environment makes new resources available, creates new challenges or opens new environmental niches. There are now at least 13 species of finches on the Galapagos Islands, each filling a different niche on different islands. All of them have evolved from one ancestral form.

Thyroid hormone is made up of tyrosine-amino acids. The thyroid hormones, triiodothyronine (T3) and its prohormone, thyroxine (T4), are tyrosine-based hormones that are produced by the thyroid gland and are primarily responsible for regulation of metabolism. T3 and T4 partially compose iodine.

Glomerulus filters blood and produces glomerular filtrate. This filtrate contains water, glucose, salts and urea. Bowman's capsule collects the filtrate and it enters the tubules.

Aneuploidy is the gain or loss of a chromosome such that the number of chromosomes is not a multiple of 23 (the human haploid number).

The oriental cockroach, also known as the waterbug, is a large species of cockroach. Its scientific name is Blatta orientalis.

The primary structure of bovine insulin was first determined by Frederick Sanger in 1951.

Within cells, organelles communicate with each other through nervous system (for short term results) and endocrine system (for long term results).

The dangerous consequences of rising levels of carbon dioxide in the Earth's atmosphere are well-documented, from destructive weather events and deadly health effects to its harmful impact on oceans, species migration, agriculture and national security.

Vitamin D is not required for blood clotting. It is required for healthy bones and teeth.

Haemophilia A, also called factor-VIII deficiency or classic haemophilia, is a genetic disorder that is caused by missing or defective factor-VIII, a clotting protein.

Pheromone is a chemical substance that is produced and released into the environment by an animal that affects the behaviour or physiology of others of its species. It produces a pungent smell in cockroaches.

These are flagellated cells with a collar of protoplasm at the base of the flagellum, numbers of which line the internal chambers of sponges. These are not found in hydra.

The facial nerve is the seventh cranial nerve. It controls the muscles of facial expression and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue and oral cavity.

The muscles surrounding the pupil of rabbit's eye are unstriated and involuntary. No stripes are found on them and they are not under the will of an individual.

It is not a ketone body. It is a byproduct in carbohydrate metabolism and is formed in Kreb's cycle.

Brain is not involved in any immune response.

Vital capacity is the maximum amount of air a person can expel from the lungs after a maximum inhalation. It is equal to the sum of inspiratory reserve volume, tidal volume and expiratory reserve volume.

Pellagra is a deficiency disease caused by a lack of nicotinic acid or its precursor tryptophan, in the diet. It is characterised by dermatitis, diarrhoea, swollen lips and mental disturbance.

Protein metabolism denotes the various biochemical processes that are responsible for the synthesis of proteins and amino acids and the breakdown of proteins into urea.

A body cavity (as in various worms) that is not the product of gastrulation and is not lined with a well-defined mesodermal membrane is pseudocoel.

It is the variation in the relative frequency of different genotypes in a small population due to the chance disappearance of a particular gene as individuals die or do not reproduce.

Glisson's capsule is a layer of connective tissues that surrounds the liver.

An unpaired parasphenoid is a dagger-shaped or inverted T-shaped bone on the ventral side that forms the floor of the cranium. It is a long and flat membraned bone.

Inhibitory neurotransmission is mediated primarily by glycine in the spinal cord and a metabolite of glutamate called gamma-aminobutyric acid (GABA).

Monocyte is a large phagocytic white blood cell with a simple oval nucleus and clear, greyish cytoplasm. It is not concerned with haemoglobin.

O gene would be inherited from the parent having A blood group and b gene from the parent having B blood group.

Radial symmetry is especially suitable for sessile animals, such as the sea anemone. It is the symmetrical arrangement of parts of an organism around a single main axis so that the organism can be divided into similar halves by any plane that contains the main axis.

Rabbits have all these teeth.

Acromegaly is a hormonal disorder that develops when our pituitary gland produces too much growth hormone during adulthood.

Measles, also known as rubeola, is a viral infection of the respiratory system. Interferons are a group of signalling proteins that are made and released by host cells in response to the presence of several pathogens, such as viruses.

Epimorphosis is the regeneration of tissues or organs through the dedifferentiation of existing and differentiated adult tissues. Adult cells dedifferentiate into a mass of cells that redifferentiates into a new structure. This is not the case of epimorphosis.

Tetanus (or lockjaw) is a serious infection caused by Clostridium tetani bacterium which produces a toxin that affects the brain and nervous system. The toxin leads to stiffness in the jaw muscles as well as other muscles.

Prolactin hormone is released by the adenohypophysis of pituitary gland. It stimulates breast development and milk production in women.

Urinogenital system in Rana tigrina is mesodermal. It arises from embryonic mesoderm.

Sweat glands, also known as sudoriferous glands, are small tubular structures of the skin that produce sweat. Sweat glands are a type of exocrine gland, which produce and secrete substances onto an epithelial surface by way of a duct.

The structures which are similar in their morphology, anatomy, genetics and embryology, but are dissimilar in their functions are called homologous organs.

Bile is a fluid that is made and released by the liver in proportion to the fat in the meal. It is stored in the gallbladder and helps with the digestion of fats.

The Indian hare (Lepus nigricollis), also known as the black-naped hare, is a common species of hare that is found in the Indian subcontinent and in Java.

Homeostasis is the tendency towards a relatively stable equilibrium between interdependent elements, especially as maintained by physiological processes.

After infective eggs are swallowed, the larvae hatch, invade the intestinal mucosa and are carried to the lungs. The larvae mature further in the lungs (10 - 14 days), penetrate the alveolar walls, ascend the bronchial tree to the throat and are swallowed.

In 1878, German physiologist Wilhelm Kuhne coined the term 'enzyme', which comes from the Greek word 'leaven', to describe this process.

Phenylketonuria (PKU) is an inborn error of metabolism involving impaired metabolism of phenylalanine.

Simple multicellular organisms, like hydra, throw out solid waste matter in the form of ammonia. They require a large amount of water as ammonia is toxic. 

Mesoderm, the middle layer, forms the skeletal muscles in a vertebrate. Middle germ layer forms connective tissues and muscle throughout the body.

Cretinism is a condition of severely stunted physical and mental growth due to untreated congenital deficiency of thyroid hormone (congenital hypothyroidism). It usually occurs due to maternal hypothyroidism.