12th biology chapter 9 MCQs (Control and Coordination)
12th Biology Chapter 9 MCQs (Control and Coordination)
1. The nervous system of mammals uses both electrical and chemical means to send signals via neurons. Which part of the neuron receives impulse?
a. Axon
b. Dendron
c. Nodes of Ranvier
d. Neurilemma
Answer : Dendron
Explanation : The part of Neuron which receives impulses are dendrites. The part which takes it away is axon.
2. ___________ is a neurotransmitter.
a. ADH
b. Acetyl CoA
c. Acetyl choline
d. Inositol
Answer : Acetyl choline
3. The supporting cells that produce myelin sheath in the PNS are _________.
a. Oligodendrocytes
b. Satellite cells
c. Astrocytes
d. Schwann cells
Answer : Schwann cells
Explanation : Schwann cells make myelin in the peripheral nervous system (PNS: nerves) and oligodendrocytes in the central nervous system (CNS: brain and spinal cord). In the PNS, one Schwann cell forms a single myelin sheath
4. A collection of neuron cell bodies located outside the CNS is called _________.
a. Tract
b. Nucleus
c. Nerve
d. Ganglionl
Answer : Ganglion
Explanation : ganglion – a collection of cell bodies located outside the Central Nervous System. The spinal ganglia or dorsal root ganglia contain the cell bodies of sensory neurons entering the cord at that region.
5. Receptors for protein hormones are located
a. in cytoplasm
b. on cell surface
c. in nucleus
d. on Golgi complex
Answer : on cell surface
Explanation : Consequently, receptors for peptide hormones are located on the plasma membrane because they have bound to a receptor protein located on the plasma membrane. Water soluble hormones come from amino acids and are located and stored in endocrine cells until actually needed.
6. If parathyroid gland of man are removed, the specific result will be
a. onset of aging
b. disturbance of Ca++
c. onset of myxoedema
d. elevation of blood pressure
Answer : Disturbance of CA++
7. Hormone thyroxine, adrenaline and non- adrenaline are formed from ———-
a. Glycine
b. Arginine
c. Ornithine
d. Tyrosine
Answer : Tyrosine
8. Pheromones are chemical messengers produced by animals and released outside the body. The odour of these substance affects………
a. skin colour
b. excretion
c. digestion
d. behaviour
Answer : Behavior
9. Which one of the following is a set of
discrete endocrine gland________
a. Salivary, thyroid, adrenal, ovary
b. Adrenal, testis, ovary, liver
c. Pituitary, thyroid, adrenal, thymus
d. pituitary, pancreas, adrenal, thymus
Answer : C
Explanation : Discrete endocrine glands – these include the pituitary (hypophysis), thyroid, parathyroid, adrenal and pineal glands.
10. After ovulation, Graafian follicle
changes into____________
a. Corpus luteum
b. Corpus albicans
c. Corpus spongiosum
d. Corpus callosum
Answer : corpus luteum
Explanation :The Graafian follicle is the structure that contains the developing egg (oocyte) which is floating in the follicular fluid. After ovulation, the Graafian follicle turns yellow due to the action of LH (luteinizing hormone) and becomes corpus luteum which secretes progesterone. So the correct option is ‘Corpus luteum
11. Which one of the following pair correctly matches a hormone with a disease resulting from its deficiency?
a. Parathyroid hormone – Diabetes
insipidus
b. Leutinising hormone – Diabetes
mellitus
c. Insulin – Hyperglycemia
d. Thyroxine – Tetany
Answer : Insulin – Hyperglycemia
12. ___________ is in direct contact of brain in human
a. Cranium
b. Duramater
c. Arachnoid
d. Piamater
Answer : Piamater
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