12th biology chapter 9 MCQs (Control and Coordination)

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Multiple choice questions.


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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