Tag: endocrine system in humans

Questions Related to endocrine system in humans

In batesian mimicry, one species resembles another, poisonous species. 
I. Poisonous species is more common than mimic
II. Poisonous species is present in same area as mimic
III. Poisonous species competes for resources with mimic
IV. Poisonous species is distinctly or brightly colored

The effectiveness of batesian mimicry can be increased by

  1. I and II

  2. I, II and III

  3. I, II and IV

  4. II, III and IV

  5. I, II, III and IV


Correct Option: C
Explanation:

Batesian mimicry refers to the resemblance of a harmless or palatable species with that of a dangerous or unpalatable one to make predators avoid them. A more common and distinct poisonous species present in the same area as mimic become familiar to predators of mimic and thereby increase the effectiveness of mimicry. Competition between mimic and poisonous species would harm either of them while mimicry is an adaptation for the protection of mimic. Thus, the correct answer is option C.

A behavioral strategy of adaptation called echolocation is found in 

  1. bats

  2. butterfly

  3. praying mantiis

  4. arctic tern


Correct Option: A
Explanation:

Bats are nocturnal flying mammals which do not employ eyesight for location of their path. food place of rest etc. They produce high frequency sound which produces echoes after striking various objects on the principle of sonar. Echoes are then analysed by bats to know their path.  

The bird which can imitate human speech is

  1. Pisttacula

  2. Hierococcyx

  3. Upapa

  4. Molpaster


Correct Option: A
Explanation:
Members of the parrot genus Pisttacula or afroasion ring necked parakeets can imitate human speech.
So, the correct answer is 'Pisttacula'.

Which of the following hormones does not have a particular target organ in the body?

  1. Growth hormone

  2. TSH

  3. Oxytocin

  4. FSH


Correct Option: A
Explanation:

Growth hormone secreted by the anterior pituitary has a widespread effect in the body. It stimulates growth of various body cells, promotes protein anabolism, absorption of calcium from bowel and conversion of glycogen to glucose.

____________ acts a transporter of hormones in animals.

  1. Spinal fluid

  2. Blood

  3. Cell

  4. All of the above


Correct Option: B
Explanation:

  • Blood is the medium of transport of animal hormones. The tissues that produce the hormones are known as the effectors while those tissues that are influenced by the effectors are called targets. Hormones are of low molecular weight and they diffuse readily. 
  • The effects brought about by the hormones are not permanent as they get readily oxidized. 

Therefore, the correct answer is option B.

Chemically hormones are 

  1. Biogenic amines

  2. Proteins, steroids and biogenic amines

  3. Proteins only

  4. Steroids only


Correct Option: B
Explanation:

Hormones are a diverse group of biochemicals, which perform a variety of roles in biological systems. Hormones are produced in endocrine glands. Hormones are responsible for maintenance of internal balance and developmental changes in the animal body. 

Chemically, hormones may be peptide (e.g., insulin), amines (e.g., catecholamines), proteins (e.g., growth hormone), steroid hormones (e.g., androgens). 

Ecdysone is secreted by

  1. Prothoracic gland

  2. Corpora allata

  3. Corpora cardiaca

  4. None of the above


Correct Option: A
Explanation:

Insects go through a process of moulting during their life cycle. The process is controlled by hormones like moulting hormone and juvenile hormones. Ecdysone is a steroidal prohormone of the major insect molting hormone, which is secreted from the prothoracic glands. Insect molting hormones (ecdysone and its homologues) are generally called as ecdysteroids.

Hormones are

  1. Produced in low amount

  2. Sometimes diffusible

  3. Non-antigenic

  4. All of the above

  5. Both A and C


Correct Option: D
Explanation:

Hormones are powerful. It takes only a tiny amount to cause big changes in cells or even whole body. Hormones are chemicals produced by special cells in glands and other organs of the body; most hormones are produced by cells in the endocrine glands. These hormones, which are produced in very small amounts, are released into the bloodstream and travel to the target organ or tissue where they exert their effect. That is why too much or too little of a certain hormone can be serious. Not all the hormones are easily diffusible. Among the diffusible lipid-soluble molecules are steroid hormones. Hormones are nonantigenic that is no antibody formation occurs against hormones.

Hormones are

  1. Internal secretion mostly discharged in the blood by endocrine glands

  2. Secretion of endocrine glands

  3. Chemical substances secreted into the gut

  4. Inorganic catalysts


Correct Option: A
Explanation:

Hormones are special chemical messengers in the body that are created in the endocrine glands like Thyroid gland produces thyroxine and calcitonin. 

Hormones are secreted directly into the blood, which carries them to organs and tissues of the body to exert their functions. Thus, the correct answer is option A.

A hormone is

  1. An enzyme

  2. A chemical messenger

  3. Both A and B

  4. None of the above


Correct Option: B
Explanation:

Hormone is a chemical messenger produced in the body that controls and regulates the activity of certain cells or organs. Hormones are secreted from the endocrine glands in the body. The glands are ductless, so hormones are secreted directly into the bloodstream.