Tag: zoology

Quizzes (289) Questions (5869)

Questions Related to zoology

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

A fall in glomerular filtration rate (GFR) activates 

  1. Juxtaglomerular cells to release renin

  2. Adrenal cortex to release aldosterone

  3. Adrenal medulla to release adrenaline

  4. Posterior pituitary to release vasopressin
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A fall in GFR can stimulate the JG cells to release renin which can stimulate the glomerular blood flow and thereby the GFR comes back to normal.

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

If the concentration of urine  decreases .......... hormone will be released.

  1. LH

  2. FSH

  3. ADH

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

A) LH is Luteinising Hormone which is not involved in the concentration of urine.

B) FSH is Follicle Stimulating Hormone which is not involved in the concentration of urine.
C) ADH (Anti Diuretic Hormone) is responsible for retaining water from the urine and preventing diuresis (dilute urine).
D) Oxytocin is the maternal hormone produced during child birth which is not involved in the concentration of urine.
So the correct answer is 'ADH'.

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

The stimulants present in tea, cocoa and cola drink

  1. Cocaine

  2. Tannin

  3. Opium

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

Caffeine is a central nervous system stimulant of the methylxanthine class of psychoactive drugs. It is the most mildest stimulant and is most widely consumed psychoactive drug. It is present in coffee, tea and cola drinks.
Therefore, the correct answer is option D.

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Absorption of ${ H } _{ 2 }O$ in DCT is controlled by

  1. ADH

  2. ACTH

  3. LH

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

The water reabsorption in the distal part of the nephron is in accordance with the body's state of hydration, under the influence of ADH and is termed as 'facultative reabsorption of water'.  ADH is secreted in the hypothalamus of brain and released into blood stream from the pituitary gland. The collecting ducts become more permeable to water due to the effect of ADH, so more water is reabsorbed by osmosis and no expenditure of ATP energy is required. The release of ADH is triggered when osmoreceptors in the hypothalamus detect an increase in osmolarity of the blood above a set point of ${300 mosm L^{-1}}$. In this situation the osmoreceptors cells also promotes thirst. Drinking reduces the osmolarity of the blood, which inhibits the secretion of ADH.

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Renin is secreted by

  1. Cortex

  2. Medulla

  3. Juxta glomerular cells

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

Juxtaglomerular cells are specialized smooth muscle cells of glomerular arterioles. They synthesize, store and secrete the enzyme renin. It plays a critical role in the renin angiotensin system and thus in renal autoregulation of the kidney.

Multiple choice zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

According to Boyle's law, the product of:.pressure and volume is a constant. Hence,

  1. if volume of lungs is increased, then pressure decreases proportionately

  2. if volume of lungs is increased, then pressure also increases proportionately

  3. if volume of lungs is increased, then pressure decreases disproportionately

  4. if volume of lungs is increased, then pressure remains the same.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
According to Boyle's law, the product of pressure and volume is a constant. Hence, if the volume of the lungs is increased, then pressure decreases proportionately.
So, the correct answer is 'if volume of lungs is increased, then pressure decreases proportionately'.
Multiple choice zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

Which of the following is true regarding expiration?

  1. Exhaled air contains more moisture

  2. Lungs are not completely emptied even after forciful exhalation

  3. Exchange of gases takes place during expiration

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

  • Expiration is a mechanism in which air which contains carbon dioxide release out from the lungs of the body.
  • This air is dry and contains more moisture from the lungs.
  • Lungs can never be empty even after force full expiration some amount of air remains in it known as residual volume.
  • The exchange of gases occurs only at cellular and alveolar site, not in expiration.
So the correct option is 'Both A and B'.

Multiple choice zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

During inspiration, the diaphragm 

  1. Expands

  2. Shows no change

  3. Contracts and flattens

  4. Relaxed to become dome shaped
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

During inspiration, the diaphragm contracts and flattens to increase the volume of the the thoracic cavity. This increase in volume leads to a decrease in intra-alveolar pressure, which is a pressure lower than atmospheric pressure and creates the pressure gradient. Due to the gradient the air is from the atmosphere is forced inside the lungs through nasal cavity.

So, the correct answer is 'Contracts and flattens'.

Multiple choice zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

Which of the following does not happen during exhalation?

  1. The space in chest cavity decreases

  2. Diaphragm goes up

  3. Air is released

  4. Ribs are pushed upward and outward
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
  • During exhalation diaphragm relaxes. 
  • The intercoastal muscles also relax.
  • This makes ribs to move down and in.
  • It reduces the volume of the chest cavity and the air is pushed out
So, the correct option is 'Ribs are pushed upward and outward'.
Multiple choice zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

In males, ______ play a role in the movement of respiratory system.

  1. Vertebrae

  2. Sternum

  3. Diaphragm

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

The diaphragm is the muscular organ situated between the thoracic cavity and the abdominal cavity. It contracts and moves downwards due to which the volume in the lungs increases and the air is inhaled. When it relaxes, the volume of the lungs decreases and the air is expelled out.

A. The vertebra is the short bone that makes up the vertebral column.
B. The sternum is the breastbone to which the ribs are attached.
C. The diaphragm is the muscular organ that plays role in the movement of the respiratory system.
D. The liver is the largest gland responsible for various metabolic activities.
Hence, the correct answer is 'Diaphragm'.