Free Control and Coordination 02 Practice Test - 10th Grade
Question 1
Nodes of Ranvier are present at:
Gaps in the cover of the nerve fibre.
Collection of nerves in the heart.
Covering of the nerve fibre.
Swelling along the nerve fibre.
SOLUTION
Solution : A
The Nodes of Ranvier, also known as myelin sheath gaps, are the gaps (approximately 1μm in length) formed between the myelin sheaths generated by Schwann cells. Electrical impulses jump from these nodes.
Question 2
The outermost covering of the brain is called ________ .
cerebrum
cranium
scalp
vertebral column
SOLUTION
Solution : B
The bony structure in our head is called the skull. Cranium is the part of the skull that encloses the brain. Three layers of meninges are present below the cranium. Eight bones enclose the brain and form the cranium and fourteen bones form the face. These bones together make up the skull.
Question 3
Which of the following is not an example of reflex action?
SOLUTION
Solution : C
Blinking of eyes is not a reflex action, but it is involuntary action. A reflex action is one which occurs spontaneously whereas involuntary action happens without the conscious choice of an organism. The way the iris in our eye adjusts the size of the pupil in response to sudden bright or dim light is a reflex action. But blinking of eyes is an involuntary action.
Question 4
"Fight or Flight" response hormone is secreted by the ______ .
SOLUTION
Solution : B
The adrenal glands are two glands that sit on top of our kidneys. They secrete the hormone known as adrenaline. Adrenaline creates a 'fight or flight' response. 'Fight or flight' is a type of response that helps us prepare to face or runaway from a dangerous situation.
Question 5
Which plant hormone promotes cell division and cell differentiation along with auxin?
Cytokinin
Gibberellin
Abscisic acid
Ethylene
SOLUTION
Solution : A
Cytokinins promote cell division, cell growth and differentiation along with auxin. Ethylene is responsible for fruit ripening. Abscisic acid helps the plant to sustain in adverse conditions. Gibberellins enable the plants to grow taller.
Question 6
Which of the following hormones contain iodine and is required to initiate the metabolism of fat?
Thyroxine
Adrenaline
Insulin
Testosterone
SOLUTION
Solution : A
Thyroxine, a hormone that contains iodine, is secreted by the thyroid gland. It increases the rate of cell metabolism and regulates growth. Thyroxine can also be made synthetically for the treatment of hypothyroidism.
Question 7
Petioles of leaves are weakened by which hormone(s)?
Ethylene
Gibberellin
Cytokinin
Abscisic acid
SOLUTION
Solution : A and D
Abscisic acid (ABA) is a plant growth regulator that derived its name because it was initially thought to be responsible for abscission (leaves or fruits falling from the plants). Abscisic acid inhibits growth and so works antagonistically to auxins and gibberellins. Ethylene in excess amount can also play a major for abscission. In leaves, ABA weakens the petiole and results in shedding of the leaves.
Question 8
The hormone involved in the regulation of calcium and phosphorus metabolism is secreted by the gland called
thyroid
thymus
pancreas
parathyroid
SOLUTION
Solution : D
The parathyroid glands are small, oval bodies that are usually four in number which lie at the back of thyroid glands. They secrete a hormone called as parathormone or parathyrin. It regulates the level of calcium in the blood plasma. Parathormone and a thyroid hormone called calcitonin work antagonistically (they work in opposite ways i.e. if one increases the calcium and phosphate levels, the other will decrease) to regulate the plasma calcium and phosphate levels.
Question 9
Match the following
A. Fight or flight1. PituitaryB. Growth Hormone releasing factor2. ThyroidC. Growth hormone3. AdrenalineD. Iodine4. Hypothalamus
A - 1, B - 3, C - 2, D - 4
A - 3, B - 4 , C - 1, D - 2
A - 3, B - 4, C - 2, D - 1
A - 3, B - 2, C - 1 ,D - 4
SOLUTION
Solution : B
Adrenaline hormone is a crucial part of the body's fight-or-flight response. Adrenaline is produced by the adrenal glands.
When the level of growth hormone is low, the hypothalamus releases growth hormone releasing factor which stimulates the pituitary gland to release growth hormone.
Iodine is necessary for the thyroid gland to make thyroxin hormone.
Question 10
Spinal nerve is a type of
SOLUTION
Solution :A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In humans there are 31 pairs of spinal nerves, one on each side of the vertebral column.