Biology

Endocrine and Exocrine Glands

594 Questions

The endocrine and exocrine glands topic explores the human body's essential secreting structures, including the pituitary, thyroid, and salivary glands. Questions often focus on gland locations, their specific secretions, and crucial physiological functions. This subject is a core component of the general science syllabus across many highly competitive examinations.

Master endocrine glandsPituitary gland locationSalivary gland functionsThyroid and ductless glandsApocrine sweat glands

Endocrine and Exocrine Glands Questions

Multiple choice zoology control and coordination in living organisms pineal gland pituitary gland and pineal gland pineal gland and thymus

According to recent knowledge, the pineal body is considered as

  1. A vestigial organ

  2. An organ of intelligence

  3. An endocrine gland

  4. An organ of involuntary action
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The pineal body (or pineal gland) is a small endocrine gland in the brain that produces melatonin, which regulates circadian rhythms.

Multiple choice zoology control and coordination in living organisms pineal gland pituitary gland and pineal gland pineal gland and thymus

"Pinealocytes cells" occurs in 

  1. Pineal body

  2. Pituitary gland

  3. Adrenal gland

  4. Thyroid gland
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pinealocytes are the main cells contained in the pineal gland, located behind the third ventricle and between the two hemispheres of the brain. The primary function of the pinealocytes is the secretion of the hormone melatonin, important in the regulation of circadian rhythms.

Multiple choice zoology control and coordination in living organisms pineal gland pituitary gland and pineal gland pineal gland and thymus

Which one of the following endocrine glands functions as a biological clock and neurosecretory transducer? 

  1. Adrenal gland

  2. Thyroid gland

  3. Pineal gland

  4. Thymus gland
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The pineal gland or epiphysis synthesizes and secretes melatonin hormone, that communicates information about environmental lighting to various parts of the body. It is attached to the roof of third ventricle in the rear part of brain. It functions as a biological clock and a neurosensory transducer, converting the neural information.  

Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Daily rhythms are associated with

  1. Pituitary gland

  2. Thymus

  3. Pineal gland

  4. Hypothalamus
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A. Pituitary gland is the master gland that regulates the activity of other endocrine glands and secretes many hormones like growth hormone, follicle stimulating hormone, thyroid stimulating hormone etc.
B. Thymus gland is associated with the development of immune system and present on the dorsal side of heart. It secretes thymosin hormone which plays an important role in the differentiation of T-lymphocytes.
C. Pineal gland is a small, rounded and reddish brown gland present at the dorsal side of forebrain. This gland secretes melatonin and serotonin hormones. Melatonin is derived from amino acid tryptophan and secreted from pineal gland. It regulates the 24 hour rhythm of our body like sleep-wake cycle, temperature etc. and also affects metabolism and pigmentation.
D. Hypothalamus is present in the forebrain. This gland secretes hormones that regulate the synthesis and secretion of hormones of pituitary gland. 
Hence, daily rhythms are associated with pineal gland. 
So, the correct answer is 'Pineal gland'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

The organ which was considered vestigial till recently but now confirmed to be endocrine gland is

  1. Thymus

  2. Pancreas

  3. Pineal

  4. Pituitary
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A. Thymus gland is associated with the development of immune system and present on the dorsal side of heart.
B. Pancreas is a heterocrine gland as it acts both as endocrine and exocrine gland. It secretes insulin hormone into blood and act as endocrine gland and when it secretes digestive enzymes and juice through pancreatic duct, it acts as exocrine gland.
C. Pineal gland is a small, rounded and reddish brown gland present at the dorsal side of forebrain. This gland secretes melatonin and serotonin hormones.
D. Pituitary gland is the master gland that regulates the activity of other endocrine glands and secretes many hormones like growth hormone, follicle stimulating hormone, thyroid stimulating hormone etc.
The organ which was considered vestigial till recently but now confirmed to be endocrine gland is pineal gland that secretes melatonin hormone associated with the regulation of rhythm of our body.
So, the correct answer is 'Pineal'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Brain sand is associated with

  1. Thymus gland

  2. Pineal gland

  3. Thyroid gland

  4. Pituitary gland
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A. Thymus gland is associated with the development of immune system and present on the dorsal side of heart. It secretes thymosin hormone which plays an important role in the differentiation of T-lymphocytes.
B. Pineal gland is a small, rounded and reddish brown gland present at the dorsal side of forebrain. This gland secretes melatonin and serotonin hormones.
C. Thyroid gland is situated between the trachea and larynx in the neck and secretes thyroxine hormone.
D. Pituitary gland is the master gland that regulates the activity of other endocrine glands and secretes many hormones like growth hormone, follicle stimulating hormone, thyroid stimulating hormone etc.
Brain sand, known as Corpora arenacea, are calcified structures found in pineal gland. 
So, the correct answer is 'Pineal gland'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Photoperiods are believed to be perceived by

  1. Hypothalamus

  2. Pineal body

  3. Pituitary gland

  4. Thyroid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • Photoperiodism is the physiological reaction to the length of day or night by an organism.
  • The pineal gland or pineal body (epiphysis or third eye) is a small endocrine gland.
  • It secretes melatonin (hormone) which regulates the wake/sleep patterns and photoperiodic functions.
  • So, the correct answer is 'Pineal body'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Endocrine gland that functions as biological clock and a neurosecretory transducer is __________.

  1. Adrenal gland

  2. Thyroid gland

  3. Thymus gland

  4. Pineal gland
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
A. Adrenal gland is present on upper side of kidneys and has two parts, adrenal cortex which secrete glucocorticoids, mineralocorticoids and sexocorticoids and adrenal medulla which secrete adrenaline and nor-adrenaline hormone.
B. Thyroid gland is situated between the trachea and larynx in the neck and secretes thyroxine hormone which increases oxygen consumption by metabolically active tissues.
C. Thymus gland is associated with the development of immune system and present on the dorsal side of heart. It secretes thymosin hormone which plays an important role in the differentiation of T-lymphocytes.
D. Pineal gland is a small, rounded and reddish brown gland present at the dorsal side of forebrain. This gland secretes melatonin and serotonin hormones. Melatonin is derived from amino acid tryptophan and secreted from pineal gland. It regulates the 24 hour rhythm of our body like sleep-wake cycle, temperature etc. and also affects metabolism and pigmentation.
So, the correct answer is 'Pineal gland'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Human endocrine gland regulating body rhythms is 

  1. Adrenal

  2. Pineal

  3. Thymus

  4. Thyroid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A. The adrenal gland is composed of two tissues - adrenal medulla (internal) and adrenal cortex (external). The adrenal medulla secretes two hormones called adrenaline or epinephrine and noradrenaline or norepinephrine. These hormones increase alertness, pupillary dilation, piloerection, sweating, heartbeat, the strength of heart contraction and rate of respiration. The adrenal cortex secretes corticoids.
B. The pineal gland secretes a hormone called melatonin. This plays a very important role in the regulation of a 24 hour (diurnal) rhythm of the body. 
C. Thymus gland secretes the peptide hormones called thymosins. It plays a major role in the differentiation of T-lymphocytes, which provide cell-mediated immunity. 
D. The thyroid gland secretes tetraiodothyronine and triiodothyronine. These controls basic metabolic rate, physical growth and metabolism of proteins, fat and carbohydrate.
So, the correct answer is 'pineal'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Pineal gland is located

  1. On kidney

  2. In brain

  3. In pancreas

  4. Near thyroid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Pineal gland, known as epiphysis, is located on dorsal side of forebrain. It is a small, rounded, stalked and reddish brown gland that resembles a pine cone. It secretes melatonin and serotonin hormone. Melatonin regulates circadian rhythm of body, pigmentation, metabolism and defence capability. Serotonin acts as a neurotransmitter and regulates functions of many organs of body like memory, sleeping, learning etc.
So, the correct answer is 'In brain'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Name the gland which is located under corpus callosum.

  1. Adrenal gland

  2. Thyroid gland

  3. Pineal gland

  4. Thymus gland
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A. Adrenal gland is present on upper side of kidneys and has two parts, adrenal cortex which secrete glucocorticoids (Cortisol), mineralocorticoids (Aldosterone) and sexocorticoids (Androgen) and, adrenal medulla which secrete adrenaline and nor-adrenaline hormone.
B. Thyroid gland is situated between the trachea and larynx in the neck and secretes thyroxine hormone which increases oxygen consumption by metabolically active tissues.
C. Pineal gland is a small, rounded and reddish brown gland present at the dorsal side of forebrain. It is located under corpus callosum (bridge between right and left sides of brain). This gland secretes melatonin and serotonin hormones.
D. Thymus gland is associated with the development of immune system and present on the dorsal side of heart. It secretes thymosin hormone which plays an important role in the differentiation of T-lymphocytes.
So, the correct answer is 'Pineal gland'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Pineal gland secretes melatonin which is connected to

  1. Colouration of skin

  2. Sleep

  3. Anger

  4. Body temperature
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Pineal gland is a small, rounded and reddish brown gland present at the dorsal side of forebrain. This gland secretes melatonin and serotonin hormones. Melatonin is derived from amino acid tryptophan and secreted from pineal gland. It regulates the 24 hour rhythm of our body like sleep-wake cycle. Its levels in the body increase during night and fall in the morning time. High levels of melatonin induce sleep and hence, it regulates sleep-wake cycle of the body.
So, the correct answer is 'Sleep'.
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

The pineal body is considered as

  1. An endocrine gland

  2. An organ concerned with voluntary actions

  3. An organ concerned with vision

  4. A vestige of third eye and endocrine gland
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The pineal body is made up of the secretory cells called the pineolocytes. It is attached to the roof of the epithalamus in the diencephalon of the forebrain. During the embryonic development, it is found attached to the brow spot between the eyes of the developing embryo. In some reptiles, the pineal gland is present in the form of the parietal eye or the pineal eye which is photosensitive and is involved in regulating the diurnal cycle. In mammals, it does not form the photosensitive structure but it is involved in the secretion of the hormone called the melatonin which regulates the sleep-wake cycle. It is degraded during the bright light and accumulates in dim light.
Hence, the correct answer is 'A vestige of third eye and endocrine gland'
Multiple choice zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

Which of the following gland in our body controls the biological clock in the human body?

  1. Pitutary gland

  2. Thyroid gland

  3. Pineal gland

  4. Parathyroid gland
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

  • The pineal gland is an endocrine gland located on the dorsal side of the forebrain. Pineal secretes a hormone called melatonin.
  • Melatonin plays a very important role in the regulation of a 24-hour (diurnal) rhythm of our body. For example, it helps in maintaining the normal rhythms of the sleep-wake cycle, body temperature. In addition, melatonin also influences metabolism, pigmentation, the menstrual cycle as well as our defense capability. Hence the gland in our body that controls biological clock is a Pineal gland.

So, the correct answer is 'Pineal gland'.