Biology

Human Excretion and Kidney Physiology

1,215 Questions

Human excretion and kidney physiology questions test your understanding of the excretory system, including the role of renal tubules and glomerular filtration. You will also find topics on urine formation, body water absorption, and excretory products. This section is vital for medical and general science exam preparation.

Glomerular filtrationRenal tubule absorptionExcretory productsRole of sodium ionsHuman excretory system

Human Excretion and Kidney Physiology Questions

Multiple choice zoology excretion to maintain homeostasis haemodialysis kidney dialysis kidney disorders

Following are four statements. Find out the correct combination. 
1. Glucose has high threshold value.
2. Urine is concentrated in Henles loop. 
3. Haemodialyser removes urea, uric acid, glucose and proteins. 
4. In glomerulus, urea, uric acid, water, glucose and plasma proteins are filtered out

  1. $1, 3, 4$
  2. $2, 3, 4$
  3. $1, 2$
  4. $1, 3$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

1) The substances which are present in blood on being filtered into the tubule are completely reabsorbed are called as high threshold substance. For example, Glucose, NaCl.Hence Glucose has a high threshold value.

2) Urine in concentrated in heles loop through a countercurrent mechanism. The flow of filtrate in the two limbs of Henle’s loop is in opposite directions and thus forms a counter current. The flow of blood through the two limbs of vasa recta is also in a countercurrent pattern. The proximity between the Henle’s loop and vasa recta, as well as the countercurrent in them, help in maintaining the concentration of urine.
So, the correct answer is '1,2'.

Multiple choice zoology excretion to maintain homeostasis haemodialysis kidney dialysis kidney disorders

Which one acts as artificial kidney in haemodialysis?

  1. Dialysing liquid

  2. Bubble trap

  3. Blood pump

  4. Dialyser
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Hemodialysis is a method for removing waste products such as creatinine and urea, as well as free water from the blood when the kidneys are in kidney failure. The mechanical device used to clean the patient's blood is called a dialyser, also known as an artificial kidney.

So, the correct option is 'Dialyser'.
Multiple choice zoology excretion to maintain homeostasis haemodialysis kidney dialysis kidney disorders

Haemodialysis is connected with

  1. Liver

  2. Spleen

  3. Stomach

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

The process of filtering the blood by the artificial kidney is known as haemodialysis. It is a method of removing excess water, nitrogenous wastes (urea), toxins from the blood in the patient who is rapidly developing loss of kidney function. It is also called renal replacement therapy. Hence haemodialysis is connected with the kidney.

So, the correct answer is 'Kidney'.

Multiple choice zoology excretion to maintain homeostasis haemodialysis kidney dialysis kidney disorders

Dialysis fluid contains all the constituents as in plasma except

  1. Electrolytes

  2. Proteins

  3. Nitrogenous wastes

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

The process of filtering the blood by the artificial kidney is known as dialysis. It is a method of removing excess water, nitrogenous wastes (urea), toxins from the blood in the patient who is rapidly developing loss of kidney function. It is also called renal replacement therapy. Dialysis fluid contains all constituents as in plasma except nitrogenous waste (Urea)

So, the correct answer is 'Nitrogenous waste'.

Multiple choice zoology excretion to maintain homeostasis haemodialysis kidney dialysis kidney disorders

Haemodialysis is done for the removal of ......... from blood

  1. Urea

  2. Glucose

  3. Amino acids

  4. All the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The process of filtering the blood by the artificial kidney is known as Haemodialysis. It is a method of removing excess water, nitrogenous wastes (urea), toxins from the blood in the patient who is rapidly developing loss of kidney function. Hence Haemodialysis is done for the removal of Urea from the blood.
So, the correct answer is 'Option A'.
Multiple choice zoology excretion to maintain homeostasis haemodialysis kidney dialysis kidney disorders

Haemodialysis is a treatment option for patients with malfunctions of

  1. Kidney

  2. Heart

  3. Liver

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

Haemodialysis is a method that is used to achieve the extracorporeal (procedure takes place outside the body) removal of waste products such as creatinine and urea from the blood when the kidneys are in a state of renal failure.

Multiple choice zoology excretion to maintain homeostasis haemodialysis kidney dialysis kidney disorders

The main waste which passes into the dialysing solution of a dialysis machine is

  1. Cellulose

  2. Glucose

  3. Water

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

The dialysis fluid contains water, glucose, salts and various substances at the correct concentration for the body. The dialysing membrane allows small particles such as water, urea and mineral ions to pass through it. There will be a net flow from the region of higher concentration (usually in the blood) to the region of lower concentration (in the dialysis fluid) by diffusion. As a result, the concentration of these small particles ends up being the same on both sides of the membrane. So the blood leaving the dialysis machine has all these substances in the same concentration as the dialysis solution. The fresh dialysis solution does not contain urea - so urea (and other impurities) pass out of the blood. They are taken away by the flow of dialysis solution. Proteins and blood cells are too big to pass through the membranes, so stay in the blood.

Multiple choice zoology excretion in living organisms excretion - animals human excretory system and products excretory system and products excretion - plants excretion in plants

Which of the following is the most toxic excretory product?

  1. $CO _2$

  2. Ammonia

  3. Urea

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

There are majorly the types of excretory product - Ammonia, Urea, and Uric acid. 

Among these Ammonia is most toxic because ammonia is basic in nature and  if ammonia is formed in more amount then it can hamper the acid base balance of our body. Increased cellular level of ammonia can result in hyperammonemia which leads to coma and death.
So, the correct option is (B).

Multiple choice zoology excretion in living organisms excretion - animals human excretory system and products excretory system and products excretion - plants excretion in plants

The following substances are the excretory products in animals. Choose the least toxic from among them.

  1. Urea

  2. Uric acid

  3. Ammonia

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

Nitrogenous waste substances such as ammonia, urea or uric acid are produced during protein metabolism according to the species. A small amount of nitrogenous waste substances are also produced during the metabolism of nucleic acids. Ammonia is the most toxic, followed by urea and then uric acid.

So the correct option is B.

Multiple choice zoology excretion in living organisms excretion - animals human excretory system and products excretory system and products excretion - plants excretion in plants

The characteristic(s) common to urea, uric acid, and ammonia is/are 
(i) They are nitrogenous wastes. 
(ii) They all need a very large amount of water for excretion.
(iii) They are all equally toxic. 
(iv) They are produced in the kidneys.

  1. (i), (ii) and (iv)

  2. (i) only

  3. (i) and (iii)

  4. (i) and (iv)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Urea, uric acid, and ammonia are known as nitrogenous wastes as they are produced during protein metabolism. 
Ammonia needs very large amount of water for excretion, second in order comes urea and then uric acid. 
Ammonia is highly toxic, then comes urea and then uric acid. 
Ammonia and urea are produced in the liver and uric acid is formed mostly in the liver and to some extent in kidneys. 
So the correct option is 'B'.
Multiple choice zoology excretion in living organisms excretion - animals human excretory system and products excretory system and products excretion - plants excretion in plants

Excretory products of mammals are useful to plants. Which of the following is not a part of such secretions?

  1. Carbon dioxide

  2. Mineral salts

  3. Bile pigments

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

The major excretory products are carbon dioxide, excess water, and nitrogenous compounds like ammonia, urea, uric acid, etc. Carbon dioxide and water are produced in the process of tissue respiration. Nitrogenous compounds are formed from the breakdown of proteins and amino acids. So, the correct option is "B" (Mineral salt).

Multiple choice zoology excretion in living organisms excretion - animals human excretory system and products excretory system and products excretion - plants excretion in plants

What is the first excretory substance in animal body?

  1. Urea

  2. Ammonia

  3. Amino acid

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

Ammonia was the first and simplest excretory substance in the animal body and is excreted as it is toxic. It requires large amounts of water for its excretion and so it is seen in most aquatic vertebrates and invertebrates.

So, the correct answer is 'Ammonia'.

Multiple choice zoology excretion in living organisms excretion - animals human excretory system and products excretory system and products excretion - plants excretion in plants

Which one is both osmoregulator as well as nitrogenous product?

  1. $NH _3$

  2. Urea

  3. Uric acid

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

Urea is both osmoregulator as well as nitrogenous waste. Urea is produced in the liver and excreted through urine. The urea helps in osmoregulation by participating in counter current system, small amounts of urea enter the thin segment of the ascending limb of Henle’s loop which is transported back to the interstitium by the collecting tubule.  

So, the correct answer is 'Urea'.

Multiple choice zoology excretion in living organisms excretion - animals human excretory system and products excretory system and products excretion - plants excretion in plants

Excretory product of spider is

  1. Ammonia

  2. Uric acid

  3. Guanine

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

The excretory product of spider is guanine. It is formed as a result of nucleotide metabolism. It does not require water for elimination because it is less soluble than uric acid and helps to conserve more water.

So, the correct answer is 'Guanine'.

Multiple choice zoology excretion in living organisms excretion - animals human excretory system and products excretory system and products excretion - plants excretion in plants

A portion of uric acid is changed into urea and ammonia by intestinal

  1. Urogenolysis

  2. Ureolysis

  3. Uricolysis

  4. Ureotolysis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The bacteria present in intestinal tract break a portion of uric acid present in the food we eat into urea and ammonia. This phenomenon is called uricolysis. Hence a portion of uric acid is changed into urea and ammonia by intestinal bacteria is called as urinalysis.
So, the correct answer is 'Uricolysis'.