Tag: zoology

Quizzes (289) Questions (5869)

Questions Related to zoology

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

Serotonin is secreted from

  1. $\alpha $- cells
  2. $\beta $- cells
  3. $\delta $- cells

  4. Enterochromaffin cells
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Serotonin is the hormone that contributes the feeling of well being and happiness in animals including humans. It is basically derived from tryptophan and is located in the gastrointestinal tract (GI tract), blood platelets and central nervous system. 90% of the total serotonin is primarily located in GI tract in Enterochromaffin cells and used for regulation of intestinal movements. Hence, answer D is correct.

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

Which of the following statements is correct?

  1. Argentaffin cells produce serotonin

  2. Villikinin is secreted by large intestine

  3. In cheilosis, deficient nutrient is nicotinamide

  4. Bleeding disease occurs due to deficiency of vitamin E
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Argentaffin cells (also known as enterochromaffin cells) are specialized cells in the gastrointestinal tract that produce serotonin.

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

Which one produces serotonin hormone in pancreas?

  1. $\alpha$-cells
  2. $\beta$-cells
  3. $\delta$-cells
  4. $\gamma$-cells
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In the pancreas, the delta cells (or D-cells) are known to produce somatostatin, but in certain contexts or specific literature, they are associated with serotonin production as well.

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

Pineal gland produces 

  1. Glucagon

  2. Aldosterone

  3. Cortisone

  4. Melatonin
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
A. Glucagon is secreted from alpha cells of islets of Langerhans of pancreas. It increases blood sugar level by stimulating glycogenolysis (i.e. break down of glucose) and gluconeogenesis (synthesis of glucose).
B. Aldosterone is a mineralocorticoid hormone secreted from the adrenal cortex. It maintains the electrolyte balance in the body by reducing the loss of sodium through urine and sweat.
C. Cortisone is a steroid hormone secreted from adrenal cortex in response to stress conditions in the body.
D. 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 'Melatonin'.