Tag: biology

Questions Related to biology

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. 

Which of the following is a hormone?

  1. Vitamin D

  2. Thyroxine

  3. Adrenaline

  4. All of the above


Correct Option: D
Explanation:

Vitamin D is a hormone produced by the kidneys that help to control the concentration of calcium in the blood and is vital for the development of strong bones. Thyroxine, also called as 3,5,3,5-tetraiodothyronine, or $T _ 4$, is one of the two major hormones secreted by the thyroid gland. Epinephrine, more commonly known as adrenaline, is a hormone secreted by the medulla of the adrenal glands.

Which one of the following flows directly into blood from the site of its production to act on an organ away from it?

  1. Enzyme

  2. Hormone

  3. Blood

  4. Lymph


Correct Option: B
Explanation:

The hormone is a regulatory substance produced in an organism and transported in tissue fluids, such as blood or sap to stimulate specific cells or tissues into action. Usually, it is a class of signaling molecules, produced by glands in multicellular organisms, that are transported by the circulatory system to target distant organs to regulate physiology and behaviour.

Which of the following has no connection with secretion of hormones?

  1. Rickets and mongolism

  2. Diabetes mellitus and cretinism

  3. Gigantism and exophthalmia

  4. Cretinism and diabetes


Correct Option: A
Explanation:

Rickets is defective mineralization or calcification of bones before epiphyseal closure in immature mammals due to deficiency or impaired metabolism of vitamin D, phosphorus or calcium, leading to fractures and deformity. 

Down syndrome, trisomy 21 or the older term mongolism is a condition in which a person is born with certain distinctive features: flat face, short neck and a degree of mental delay (mental retardation). It is a genetic disorder caused by the presence of all or part of an extra third copy of chromosome 21.