Tag: excretion and osmoregulation

Questions Related to excretion and osmoregulation

Separation of amino acid into amino and carboxyl group is known as

zoology excretion and osmoregulation micturition urine and urine formation urine formation

  1. Deamination

  2. Excretion

  3. Amination

  4. Egestion

Show answer
Correct Option: A
Explanation:

Deamination is the process by which amino acids are broken down if there is an excess of protein intake. Deamination takes place in the liver. The amino group is removed from the amino acid and converted to ammonia. Ammonia is toxic to humans, so the enzymes convert it to urea or uric acid by addition of carbon dioxide molecules, which also takes place in the liver. Urea and uric acid is excreted in urine.

A person who is starving, that is not having food and is
surviving only on water will have

zoology excretion and osmoregulation micturition urine and urine formation urine formation

  1. More urea in his blood

  2. Less urea in his urine

  3. Less fats in his urine

  4. More glucose in his blood

Show answer
Correct Option: B
Explanation:

As urea is the main excretory product of mammals and if the person is starving, he will have less urea in his urine.

Out of the following, choose the correct path of urine in our body.

zoology excretion and osmoregulation micturition urine and urine formation urine formation

  1. Kidney ---> ureter ---> urethra ---> urinary bladder

  2. Kidney ---> urinary bladder ---> urethra ---> ureter

  3. Kidney ---> ureter ---> urinary bladder ---> urethra

  4. Urinary bladder ---> kidney ---> ureter ---> urethra

Show answer
Correct Option: C
Explanation:

The urinary system consists of the kidneys, ureters, urinary bladder, and urethra. The kidneys filter the blood to remove wastes and produce urine. The ureters, urinary bladder, and urethra together form the urinary tract, which acts as a plumbing system to drain urine from the kidneys, store it, and then release it during urination, respectively. Besides filtering and eliminating wastes from the body, the urinary system also maintains the homeostasis of water, ions, pH, blood pressure, calcium and RBCs.

Choose the correct answers from the following given.
Which of the following vitamins is generally excreted in human urine?

zoology excretion and osmoregulation micturition urine and urine formation urine formation

  1. Vitamin C

  2. Vitamin A

  3. Vitamin K

  4. Vitamin D

Show answer
Correct Option: A
Explanation:

Vitamin C is excreted in human urine because it is water soluble vitamin. 

So the correct answer is Vitamin C.

Choose the correct answer from the alternatives given.
The hormone that controls the output of urine is:

zoology excretion and osmoregulation micturition urine and urine formation urine formation

  1. epinephrine

  2. vasopressin

  3. aldosterone

  4. oxytocin

Show answer
Correct Option: B
Explanation:

(A) Epinephrine is related to the adrenal gland and is released during stress or emergency situation. 

(B) Vasopressin is stimulated when there is excessive loss of fluid from the body. This facilitates water reabsorption from the latter parts of the tubule, thereby preventing diuresis. 
(C) Aldosterone Acts mainly at the renal tubules and stimulates the reabsorption of Na+ and water and excretion of K+ and phosphate ions.
(D) Oxytocin acts on the smooth muscles of our body and stimulates their contraction.
So the correct answer is vasopressin.

In humans, water is

zoology excretion and osmoregulation micturition urine and urine formation urine formation

  1. found in the glomerular filtrate

  2. reabsorbed from the nephron

  3. in the urine

  4. all of the above

Show answer
Correct Option: D
Explanation:

  • In nephrons, potassium ion, sodium chloride, calcium ion, amino acids, glucose, bicarbonate ion, and water are reabsorbed back into the bloodstream. 
  • The glomerular filtrate contains a lot of water, but also important molecules like glucose, amino acids, salts, and excretory material, urea.
  • Urine is an aqueous solution of greater than 95% water. Other constituents include urea, chloride, sodium, potassium, creatinine and other dissolved ions, and inorganic and organic compounds. Urea is a non-toxic molecule made of toxic ammonia and carbon dioxide.

So, the correct answer is 'all of the above
'.

Consider the following statements each with two blanks.


(i) Annelids have (1) and insects have (2) for excretion.
(ii) Blood enters the glomerulus via (3) arteriole and leaves via (4) arteriole.
(iii) During micturition, the urinary bladder (5) and urethral sphincters (6).
Which one of the following options correctly fills the blanks in any two of the above statements?

zoology excretion and osmoregulation micturition urine and urine formation urine formation

  1. $(1)$-Malphigian tubules, $(2)$-Flame cells, $(5)$- Contracts, $(6)$- Relax

  2. $(3)$-Afferent, $(4)$-Efferent, $(5)$- Contracts, $(6)$- Relax

  3. $(1)$- Nephridia, $(2)$-Malpighian tubules, $(5)$- Relaxes, $(6)$- Contract

  4. $(3)$- Efferent, $(4)$-Afferent, $(5)$- Relaxes, $(6)$- Contract

Show answer
Correct Option: B
Explanation:

  1. Annelids have nephridia and insects have malphaghian tubules for excretion.
  2. Blood enters the glomerulus via afferent arteriole and leaves via efferent arteriole.
  3. During micturition, the urinary bladder contract and urethral sphincters relax to let the urine pass out from the body.
So, the correct answer is (B);

Consider the  following four statements (i) - (iv) and select the option that correctly identifies the true $(T)$ and false $(F)$ ones .


(i) Micutrition is carried out by a reflex.
(ii) ADH helps in water elimination making the urine hypotonic.
(iii) Protein-free fluid is filtered from blood plasma into the Bowman's capsule.
(iv) Glucose is actively reabsorbed in the proximal convoluted tubule.

zoology excretion and osmoregulation micturition urine and urine formation urine formation

  1. (i) $T$ , (ii) $F$ , (iii) $T$, (iv) $T$

  2. (i) $T$ , (ii) $T$ , (iii) $F$, (iv) $F$

  3. (i) $F$ , (ii) $F$ , (iii) $F$, (iv) $T$

  4. (i) $F$ , (ii) $T$ , (iii) $F$, (iv) $T$

Show answer
Correct Option: A
Explanation:
  • Micturition is carried out by the parasympathetic reflexes.
  • ADH hormone helps in the reabsorption of water making the urine hypertonic.
  • All the large proteins, cells remain in the blood and pass into the tubule due to the presence of bowman's capsule.
  • Glucose, and other important ions get reabsorbed from the PCT.
  • Thus, the correct answer is 'T, F, T, T'.

The excretory waste materials eliminated by kidney as aqueous solution is called as

zoology excretion and osmoregulation micturition urine and urine formation urine formation

  1. Urine

  2. Urea

  3. Uric acid

  4. Ammonia

Show answer
Correct Option: A
Explanation:

Mammals, many terrestrial amphibians mainly excrete urea and are called ureotelic animals. The urea is excreted in aqueous solution in more liquified form, called urine. Urine formation involves three main processes namely, glomerular filtration, reabsorption and secretion, that takes place in different parts of the nephron.

The outline of principal events of urination is given below in random manner. 
(i) Stretch receptors on the wall of urinary bladder send signals to the CNS.
(ii) The bladder fills with urine and becomes distended. 
(iii) Micturition.
(iv) CNS passes on motor messages to initiate the contraction of smooth muscles of bladder and simultaneous relaxation of urethral sphincter.

zoology excretion and osmoregulation micturition urine and urine formation urine formation

  1. (i) $\rightarrow$ (ii) $\rightarrow$ (iii) $\rightarrow$ (iv)

  2. (iv) $\rightarrow$ (iii) $\rightarrow$ (ii) $\rightarrow$ (i)

  3. (ii) $\rightarrow$ (i) $\rightarrow$ (iv) $\rightarrow$ (iii)

  4. (iii) $\rightarrow$ (ii) $\rightarrow$ (i) $\rightarrow$ (iv)

Show answer
Correct Option: C
Explanation:

Process of urination involves these following steps: - 

  1.  Filling of the urinary bladder with the urine and after filling, the bladder becomes distended.
  2. The filled bladder stretches the receptors present on its wall and send signals to the CNS.
  3. After receiving the signal the CNS passes the signal to initiate the contraction of smooth muscles of bladder and simultaneous relaxation of the urethral sphincter.
  4. Ultimately after the contraction of detrusor muscles of the urinary bladder and relaxation of the sphincter causes Micturition.
So, the correct answer is (ii) → (i) → (iv) → (iii).