Biology · General Awareness

Human Endocrine System

1,395 Questions

The human endocrine system comprises glands that secrete hormones to regulate bodily functions like metabolism, growth, and reproduction. Competitive exams frequently test the specific roles of hormones such as adrenaline, insulin, and progesterone. Use these questions to master the locations and functions of different hormones.

Hormone functionsIslets of LangerhansFight or flight responseBlood pressure regulationFemale sex hormonesWater soluble hormones

Human Endocrine System Questions

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Hormones can be differentiated from neurotransmitters on the basis of the fact that

  1. Hormones modify cellular activity

  2. Hormones are secreted into the bloodstream

  3. Hormones produce a change in animal behavior

  4. Hormones attach to receptors on the cell surface

  5. Hormones are released in response to external stimuli
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Neurotransmitters are the chemical messenger that is released from an axon terminal of a neuron in response to an action potential. Whereas a hormone is a long distance chemical mediator that is secreted by an endocrine gland into the blood which is transported to target cells. Thus, the correct answer is option B.
Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Which of the following hormones is derived from a single amino acid?

  1. Thyroxine

  2. Oxytocin

  3. Estradiol

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

Hormones can be classified based on their chemical nature like amino acid derivative hormones, peptide hormones, iodothyronines and steroid hormones. Hormones like epinephrine, norepinephrine, thyroxine are derived from amino acids. Epinephrine and norepinephrine are released by renal medulla. These are derived from single amino acid tyrosine. Thyroxine is released by thyroid gland. It is also derived from tyrosine amino acid by the addition of iodine.

Thus, the correct answer is 'Epinephrine.'

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

How many of these hormones are lipid soluble? FSH, LH, Iodothyronine, Epinephrine, Aldosterone, Progesterone.

  1. Two

  2. Three

  3. Four

  4. One
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Lipid soluble hormones are the hormones that can be dissolved in fats rather than in water. They are usually formed from cholesterol and lipids, therefore fat-soluble hormones can pass through cell membrane. Examples of lipid soluble hormones are progesterone and aldosterone.
So the correct answer is 'Two'.
Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Correct hormonal sequence in the rate of man is 

  1. Oestrogen, Fs, progesterone

  2. Oestrogen, progesterone, FSH

  3. FSH, progesterone, oestrogen

  4. FSH, oestrogen , progesterone
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The secretion of gonadotropin s (LH & FSH) increase gradually during the follicular phase and stimulates follicular development as well as secretion of oestrogens and progesterone. 


So the correct option is " FSH, oestrogen, progesterone". 

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Which of the following hormone is steroid?

  1. Epinephrine

  2. Thyroxine

  3. Estrogen

  4. Gonadotropin
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The steroids are organic compounds involved in biological processes. Steroid hormones are generally synthesized from cholesterol in gonads and adrenal glands. They are basically lipids. For example, estrogen, progesterone, testosterone, etc.
Thus, the correct answer is 'Estrogen.'
Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Hormone responsible for the absorption of water in DCT is

  1. ADH

  2. ACTH

  3. Oxytocin

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

Antidiuretic hormone (ADH), also known as vasopressin, is primarily responsible for increasing water reabsorption in the distal convoluted tubules and collecting ducts of the kidney. This action helps the body retain water and concentrate urine.

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Hormones are produced at a particular centralized site and transported throughout the organism by means of 

  1. a series of synapses

  2. an integrated neural pathway system.

  3. cellular communication

  4. an internal transport system
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Hormones are chemical messengers secreted by endocrine glands into the bloodstream or equivalent circulatory channels. This internal transport system distributes them to target organs and tissues throughout the body.

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Steroid-based hormones are able to act inside the cell. This is possible because

  1. there are no receptors for hormones on the cell surface

  2. hormones must interact with the nucleus to have an effect.

  3. proteins carry them into the cell

  4. steroid-based hormones are hydrophobic molecules that can pass through the cell membrane.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Steroid based hormones are fat soluble so they can enter the cell easily after which they bind to the specific steroid receptors and perform the required activities on the cell. And because they are lipids(hydrophobic molecules)  so they can enter the cell membrane.
So, the correct option is 'steroid-based hormones are hydrophobic molecules that can pass through the cell membrane'
Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

The mode of action of steroid hormones involves

  1. a second messenger.

  2. modification of enzyme activity.

  3. stimulation of DNA replication.

  4. stimulation of mRNA transcription
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Steroid hormones are lipid soluble and pass easily through the cell membrane to bind to intracellular receptors. This hormone receptor complex then enters the nucleus and directly stimulates mRNA transcription.

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

All of the following statements are true about hormones except

  1. They are transporated by the circulatory system

  2. They bind to receptors on target cells

  3. They must be present in large quantities to have an effect

  4. They are secreted by endocrine glands

  5. They can affect organs of the body that are far removed from their site of synthesis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
1. Hormones are produced by specialized glands(endocrine glands) and are secreted directly into the bloodstream.
2. Hormones are transported by the bloodstream from the endocrine cells to serve as ‘chemi­cal messenger’ which act on target cells or organs by regulating the rates of specific metabolic reactions. 
3. Hormones exert their effects not where they are locally produced, but on other tissues of the body. 
4. Hormones are required in very small amounts and their effect may be excitatory or inhibitory depending upon their concentration and the physiological state of the responding tissue. Hence, All of the following statements are true about hormones except They must be present in large quantities to have an effect. 
So, the correct answer is 'They must be present in large quantities to have an effect'.  
Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Choose the peptide hormone from the following

  1. adrenaline

  2. Insulin

  3. Testosterone

  4. Progesterone
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Peptide hormones are the one which have single or multiple long amino acid chain/s. Insulin is a peptide hormone with two amino acid chains, one with 21 and other with 30 amino acids. This makes option B correct. 

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

Chemically hormones are

  1. Biogenetic amines only

  2. Proteins, steroids and biogenetic amines

  3. Proteins only

  4. Steroids only
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Hormones are certain essential substances in our bodies that are released by our body's endocrine system.  They are chemical messengers in our bodies that transmit messages for the action of various glands in our bodies and their secretions. 

Hormones are made up of certain chemical substances like proteins,  steroids and biogenetic amines. So, option B " proteins, steroids and biogenetic amine" is the correct option.

Multiple choice zoology endocrine system and chemical co-ordination classification of hormones endocrine system and hormone hormones and metabolism

With increasing age, secretion of which of the following reduces to almost half?

  1. GTH

  2. Melatonin

  3. Estrogen

  4. ADH
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The primary function of estrogen is development of female secondary sexual characters. These include breasts, endometrium, regulation of the menstrual cycle, etc. In males, estrogen regulates certain functions of the reproductive system important for maturation of sperms. The loss of estrogen is a central feature of menopause, which usually occurs around age 50. However, estrogen production begins to decline in most women before they turn 40. 
So, the correct option is 'Estrogen'.