All Free Biology MCQs with Answers

• A. Hair end organs
• B. Pacinian corpuscles
• C. Meissner's Corpuscles
• D. All of these

Explanation: Meissner's corpuscles (or tactile corpuscles) are a type of mechanoreceptor. They are touch receptors.

• A. Alveolar lungs
• B. Seven cevical vertebrae
• C. Thecodont dentition
• D. Ten pairs of cranial nerves

Explanation: Correct option is D. In higher vertebrates (reptiles, birds, mammals) there are 12 pairs of cranial nerves.

• A. Thermoregulation
• B. Vision
• C. Memory
• D. Tactile sensation-response when pricked with a needle.

Explanation: Correct option is D. Medulla oblongata is the bottom-most part of your brain.

• A. Xanax
• B. Lorazepam
• C. Butabarbital
• D. Diazepam
• E. All of these

Explanation: Hypnotic drugs or sleeping pills are a type of sedative. These drugs have a relaxing effect on the CNS and are used to induce sleep in…

• A. Pons of medulla
• B. Thalamus and limbic system
• C. Pons and medulla
• D. Hypothalamus and limb

Explanation: The diencephalon is a part of the brain that is located between the cerebrum and the midbrain.

• A. Hair end organs
• B. Pacinian corpuscles
• C. Meissner's Corpuscles
• D. All of these options are correct

Explanation: Meissner's corpuscles respond to touch and low-frequency vibration. Ruffini endings detect stretch, deformation within joints, and warmth.

• A. Wallace
• B. Lamark
• C. Iyell
• D. Darwin

Explanation: Darwin used the word instinct in several different ways to refer to what impels a bird to breed; to a disposition, such as courage or…

• A. Voluntary action
• B. Involuntary action
• C. Saltatory conduction
• D. None of these

Explanation: Involuntary actions are actions that are not controlled by our will. Reflex actions are sudden actions in response to something.

• A. White matter
• B. Gray matter
• C. Cell bodies
• D. Non-myelinated nerve fibres

Explanation: A is correct since the outer portion of the spinal cord consists of white matter because of the fatty substance (myelin) that surrounds…

• A. Nephrons
• B. Myoid cells
• C. Neurons
• D. None of these options are correct

Explanation: Neuroglia maintain homeostasis, form myelin, and provide support and protection for neurons in the nervous systems.

• A. Vasopressin and ADH
• B. Epinephrine and Norepinephrine
• C. Oestrogen and Testosterone
• D. Insulin and Glucagon

Explanation: Epinephrine and norepineprin are both amino acid derived hormones, and thus are relatively small, as compared to peptide hormones, which…

• A. Glucagon
• B. Epinephrine
• C. Thyroxin
• D. Estogen

Explanation: Estrogen is a steroid hormone that plays a crucial role in the development and regulation of the female reproductive system.

• A. Fore brain
• B. Mid brain
• C. Hind brain
• D. Spinal cord

Explanation: The forebrain is the largest region of the brain, containing the entire cerebrum and thalamus, along with other nested structures.

• A. Dyspepsia
• B. Septecemia
• C. Anorexia
• D. Bulimia

Explanation: Bulimia nervosa is an eating disorder in which a person may eat a lot of food at once and then try to get rid of the food by vomiting…

• A. Blood Glucose
• B. Blood Ammonia
• C. Blood 𝑝H
• D. Blood flow

Explanation: Baroreceptors are mechanoreceptors located in blood vessels near the heart that provide the brain with information about blood volume and…

• A. Pons
• B. Mid brain
• C. Cerebellum
• D. Medulla

Explanation: The Medulla oblongata is the posterior portion of the brain. Special reflexes such as heart beat, respiratory movement, salivary…

• A. Paccinian's corpuscles
• B. Mechanoreceptors
• C. Merkel disks
• D. Both B and C

Explanation: Merkel disks are touch receptors. Receptors for touch and pressure are also called Mechanoreceptors. Thus, option D is the correct answer.

• A. Prolactin
• B. IH
• C. FSH
• D. Oxytocin

Explanation: Oxytocin is the hormone released by the posterior pituitary that stimulates the contraction of uterine(during labor) and mammary gland…

• A. Oxytocin - posterior pituitary - growth and maintenance of mammary glands
• B. Melatonin - ­pineal gland - regulates the normal rhythm of sleep wake cycle.
• C. Progesterone - corpus luteum- stimulation of growth and activities of female secondary sex organs
• D. Atrial natriuretic factor - atrial wall - increases the blood pressure

Explanation: Oxytocin is produced by the hypothalamus and generally secreted by the posterior pituitary.

• A. Cancer of the thyroid gland
• B. Oversecretion of pars distali
• C. Deficiency of iodine in diet
• D. Low secretion of growth hormone

Explanation: Iodine is needed for the synthesis of T3 and T4. Iodine binds to the tyrosine residues in thyroglobulin, which is then hydrolysed into…