Biology

Human Excretion and Kidney Physiology

1,152 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 and osmoregulation micturition urine and urine formation urine formation

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

  1. Urine

  2. Urea

  3. Uric acid

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

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

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.

  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)
Reveal answer Fill a bubble to check yourself
C Correct answer
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).

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

Urine leaves the kidney as

  1. Water

  2. Blood

  3. Interstitial fluid

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

Urine is a liquid excretory product of the body excreted by the kidneys through a process called urination (or micturition) and excreted through the urethra. Urine contains urea and water. A urea is toxic it needs water to be excreted from the body.

So, the correct answer is option A.

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

Urine is stored in

  1. Ureter

  2. Kidney

  3. Urinary bladder

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

The blood is filtered by the kidney and the urine is formed. Urinary bladder is the organ that collects urine excreted by the kidneys before disposal by urination. It is a hollow muscular, and distensible (or elastic) organ. Urine enters the bladder via the ureters and exits via the urethra. 

So, the correct answer is option C.

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

Largest amounts of nitrogen are excreted through

  1. Sweat

  2. Faeces

  3. Breath

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

The urinary system is involved in the excretion of nitrogenous waste products such as urea, uric acid or ammonia. The excretion of nitrogenous waste from animals is important because if it is allowed to build up, it can prove toxic. The waste product is formed due to the breakdown of the amino acids.

So, the correct answer is option D.

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

The filling of the urinary bladder essentially requires

  1. Relaxation of detrusor muscle

  2. Contraction of internal sphinet

  3. Stimulation of sympathetic nerve

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

The muscular part of the bladder wall is called the detrusor muscle. The internal and external sphincter muscles surround the bladder neck and the urethra. While the bladder is filling, the detrusor muscle is relaxed so the bladder wall can expand, and the sphincter muscles are contracted to keep the urethra closed. Sympathetic stimulation is predominant during bladder filling, and the parasympathetic causes emptying. Thus, option D is correct and other options are wrong.

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

The feeling of fullness sensation of urine is marked if the volume of urine increases upto

  1. 200 c.c

  2. 300 c.c

  3. 600 c.c

  4. 1000 c.c
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The feeling of fullness sensation of urine is marked if the volume of urine increases up to 600 c.c.

Urination is the release of urine from the urinary bladder through the urethra to the urinary meatus outside of the body. It is also known medically as micturition.
Physiologically, urination involves coordination between the central, autonomic, and somatic nervous systems.In the adult, the volume of urine in the bladder that normally initiates a reflex contraction is about 300–400 millilitres.
Therefore, the correct answer is option C.

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

Protein rich diet brings about relatively no change in which one of the following constituents of urine?

  1. Creatinine

  2. Ammonium salt

  3. Urea

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

Urine which is a waste product of the human system is 95% water. Remaining 5% contains urea, uric acid, creatinine, sodium chloride, hormones, carbohydrates, fatty acids, enzymes, mucins and pigments. While diets play a role in the excretory systems, the protein rich diet does not bring in any changes in the uric acid levels in urine.

Therefore, the correct answer is option D.

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

What is not a correct fact about the micturition?

  1. 1-2 litres production/day
  2. On standing urine gives pungant odour because it converts to ${ H } _{ 2 }S$ by bacteria.

  3. Normal pH of urine is 6.0

  4. Uric acid forms 0.3% of a normal urine sample
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The normal range for 24-hour urine volume is 800 to 2,000 milliliters per day (with a normal fluid intake of about 2 liters per day). Micturition or urination is the process of expelling urine from the bladder. This act is also known as voiding of the bladder. The excretory system in humans includes a pair of kidneys, two ureters, a urinary bladder, and a urethra. So the correct option is '1-2 liters production /day'.

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

Choose the correct answers from the following given.
Waste products of adenine and guanine metabolism are excreted by man as

  1. urea

  2. uric acid

  3. ammonia

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

The purines metabolism occur by the action of the enzymes released by the liver and intestine which help in the formation of xanthine which finally converts into uric acid as the end product.

Hence the correct answer is B.

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

Micturition is

  1. Removal of urea from blood

  2. Removal of uric acid

  3. Passing out urine

  4. Removal of faecal matter
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Urination is the release of urine from the urinary bladder through the urethra to outside of the body. It is also known medically as micturition. Micturition occurs when the bladder neck and the external urinary sphincter relax and the bladder contracts, allowing for the unobstructed expulsion of urine.

Multiple choice biology animal physiology kidney dialysis kidney disorders disorders of kidney

Antidiuretic hormone is put into the blood by the

  1. Hypothalamus

  2. Pituitary gland

  3. Liver

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

Antidiuretic hormone (ADH) is a hormone that is produced in a part of the brain called as the hypothalamus. It is then stored and released from the pituitary gland, a small gland at the base of the brain. ADH acts on the kidneys to control the amount of water excreted in the urine

So, the correct answer is 'Pituitary gland'

Multiple choice biology animal physiology kidney dialysis kidney disorders disorders of kidney

Uraemia is an excretory disorder in which

  1. The tubules of kidney reabsorb urea in large amount

  2. Concentration of urea goes high in the blood because the tubules are not able to remove it from the blood

  3. Urea is produced in excess in the body

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Urea is very soluble and a small molecule, so it is relatively easily passed out by the kidneys as a solution in water. Uraemia is an excretory disorder in which there is increased level of urea in the blood. It is caused due to the renal failure. In uremia, the tubular absorption of urea in collecting duct is inhibited. Progressive weakness and easy fatigue, loss of appetite due to nausea and vomiting, muscle atrophy, are some common symptoms of ureamia. 

Multiple choice evs excretion in living organisms other systems in the body excretory system in human human excretory organs

Which of the following are excretory products in animals?

  1. Urea

  2. Uric acid

  3. Ammonia

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

In animals, the main excretory products are, Ammonia- protozoans, crustaceans, platyhelminths, cnidarians, poriferans, echinoderms, fishes, larvae/tadpoles of amphibians are ammonotelic. Urea -cartilaginous fish, few bony fishes, adult amphibians and mammals including humans are uricotelic, Uric acid-terrestrial arthropods (including insects), lizards, snakes, and birds are uricotelic.

So, the correct answer is 'All the above'