Which of the following endocrine glands is not found in pair in humans?
- A.Adrenal
- B.Pituitary
- C.Testis
- D.Ovary
Correct answer
Explanation
The correct answer is B, Pituitary. The pituitary is a single, pea-sized gland at the base of the brain, while the other three come in pairs.
The pituitary hangs from the hypothalamus in a bony hollow of the skull, the sella turcica. It is called the master gland because its hormones, such as growth hormone, TSH, ACTH, FSH and LH, control many other glands. Other unpaired endocrine glands are the pineal, the thyroid (one gland with two lobes), the thymus and the pancreas. Paired glands include the adrenals, the gonads and the parathyroids, usually four in number.
A is wrong because there are two adrenal glands, one on top of each kidney.
C is wrong because males have a pair of testes in the scrotum.
D is wrong because females have a pair of ovaries, one on each side of the uterus.
Exam tip: pituitary, master gland, single, controlled by the hypothalamus; adrenals sit on the kidneys in a pair.
Practice Questions
View allConsider the following actions :
1. Detection of car crash/collision which results in the deployment of airbags almost instantaneously
2. Detection of accidental free fall of a laptop towards the ground which results in the immediate turning off of the hard drive
3. Detection of the tilt of the smartphone which results in the rotation of display between portrait and landscape mode
In how many of the above actions is the function of accelerometer required?
- A.Only one
- B.Only two
- C.All three
- D.None
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An accelerometer measures acceleration, including the pull of gravity, and each of the three actions depends on reading it. An accelerometer is a small sensor, today usually a MEMS (micro-electro-mechanical system) chip, that senses changes in speed and the direction of gravity.
Read the full explanation →Consider the following statements :
1. Carbon fibres are used in the manufacture of components used in automobiles and aircrafts.
2. Carbon fibres once used cannot be recycled.
Which of the statements given above is/are correct?
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
Show answer
Carbon fibre is widely used in cars and aircraft for its strength and low weight, and it can be recovered and recycled.
Read the full explanation →Which one of the following cell organelles contains DNA?
- A.Golgi apparatus
- B.Mitochondrion
- C.Lysosome
- D.Endoplasmic reticulum
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Mitochondria carry their own small, circular DNA and their own ribosomes. Mitochondria are the powerhouses of the cell, where aerobic respiration makes ATP.
Read the full explanation →Which set of vegetables is underground stem or modified stem of a plant?
- A.Potato, artichoke, round gourd
- B.Onion, garlic, carrot
- C.Potato, onion, garlic
- D.Potato, garlic, turnip
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All three are underground modified stems: the potato is a stem tuber, and onion and garlic are bulbs. A stem can be told from a root by its nodes and buds.
Read the full explanation →A sound wave having frequency of 300 Hz is travelling in an unknown medium. Its wavelength is not known. It travels a distance equal to 150 times its wavelength in time t. The value of t is :
- A.0.5 s
- B.1 s
- C.1.5 s
- D.2 s
Show answer
A wave moves forward by one wavelength in each cycle, so 150 wavelengths take 150 cycles, and 150 cycles at 300 per second take half a second.
Read the full explanation →