Biology MCQs

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The pituitary gland or hypophysis is located in one of the bones at the base of the skull. It has two portions viz. anterior hypophysis and posterior hypophysis.
The anterior part produces two hormones that work directly viz. growth hormone (GH) and prolactin; and four tropic hormones {tropic hormones regulate the other endocrine glands} viz. adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH), luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
The posterior part releases two hormones produced in the hypothalamus viz. oxytocin and antidiuretic hormone (ADH or vasopressin).

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Wilson’s disease is a genetic disorder in which excess copper builds up in the body. Symptoms are typically related to the brain and liver. Some of the symptoms are vomiting, weakness, fluid build up in the abdomen, swelling of the legs, etc.

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Anesthesia which allows patients to undergo surgery without the distress and pain they would otherwise experience, has been practiced by man since ancient times. Opium (poppy) is the most ancient source of anesthesia preparations.

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Alveoli are tiny sacs in our lungs. The main function of the alveoli is the exchange of carbon dioxide for oxygen in the lungs.

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Alzheimer's is caused by brain cell death. It is a neurodegenerative disease, which means there is progressive brain cell death that happens over a course of time. It is caused due to deficiency of acetylcholine.

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Drugs that bind to receptor sites and inhibit their natural function are called antagonists. These drugs are useful when a message needs to be blocked.
Antagonists bind to receptors but do not activate them. They compete with available agonists for receptor binding sites. Antagonists block the access or attachment of the body’s natural agonists, usually neurotransmitters, to their receptors. This prevents or reduces cell responses to natural agonists.
Antagonists still cause a response, but this is through blocking the actions of agonists.
Agonist and antagonist drugs can be used together in people with asthma. For example, albuterol can be used with ipratropium.

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Pneumatophores are specialized root structures that grow out from the water surface and facilitate the aeration necessary for root respiration in hydrophytic trees such as many mangrove species.

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There are two types of bone marrow: red marrow (also known as myeloid tissue) and yellow marrow. Red blood cells, platelets and most white blood cells arise in red marrow; some white blood cells develop in yellow marrow.

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Plants absorb ammonium and nitrate during the nitrogen assimilation process, after which they are converted into nitrogen-containing organic molecules, such as amino acids and DNA. Animals cannot absorb nitrates directly. They receive their nutrient supplies by consuming plants or plant-consuming animals.

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Rickets is a skeletal disorder that’s caused by a lack of vitamin D, calcium, or phosphate. These nutrients are important for the development of strong, healthy bones. People with rickets may have weak and soft bones, stunted growth, and, in severe cases, skeletal deformities.