Tag: excretion in living organisms

Questions Related to excretion in living organisms

Length of female urethra is

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

  1. 15 cm

  2. 10 cm

  3. 4 cm

  4. 2 cm

Show answer
Correct Option: C
Explanation:

Urethra in females serves the sole purpose of excretion of urine. It extends from the base of urinary bladder to the urinary meatus hence having a length of 4 cm.

So, the correct answer is '4 cm'.

The correct sequence of urine movement is

evs - i excretion in living organisms other systems in the body excretory system in human human excretory organs

  1. Bladder --> Kidney --> Ureter -->Urethra

  2. Bladder -->Urethra -->Kidney -->Ureter

  3. Kidney -->Bladder -->Ureter --> Urethra

  4. Kidney -->Ureter -->Bladder -->Urethra

Show answer
Correct Option: D
Explanation:
Urine is formed in the kidney. The tubes which connect the kidney and urinary bladder are known as the ureter. From the kidney, urine is propelled into the urinary bladder through ureters which are made of smooth muscle fibres. The bladder stores urine, allowing urination to be infrequent and can be controlled. The urethra is a long tube which connects urinary bladder to the urinary meatus for removal of urine from the body. In males, urethra travels through the penis and meet the urethral meatus located at the tip of the penis. In females, urethra connects to the urethral meatus above the vagina. The urethra is also known as the urinary opening. So the correct sequence of urine movement is Kidney -->Ureter -->Bladder--> Urethra.
So, the correct answer is 'Kidney -->Ureter -->Bladder -->Urethra'.

Urine is excreted out of the body through

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

  1. Pelvis

  2. Ureter

  3. Urinary bladder

  4. Urethra

Show answer
Correct Option: D
Explanation:

a) Pelvis is the lower region of abdomen which houses various organs. 

b) Ureter carries urine from kidneys to urinary bladder hence, it does not excrete urine out of the body. 
c) Urinary bladder only stores the urine. 
d) Urethra carries urine from the urinary bladder to the outside of the body. 
So, the correct answer is 'Urethra'.

Which of the following does not help in excretion?

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

  1. Liver

  2. Sweat glands

  3. Pancreas

  4. Both A and B

Show answer
Correct Option: C
Explanation:
In liver the toxic ammonia is converted to urea which is filtered by kidney to form urine. Sweat glands help in excretion of excess salts and water in the form of sweat. Hence, both these organs help in excretion. Pancreas on the other hand, secrete the hormones insulin and glucagon and digestive enzymes. Hence, it has endocrine and digestive functions but not excretory functions.
So, the correct answer is 'Pancreas'.

Urinary bladder opens to the outside through

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

  1. Nephron

  2. Glomerulus

  3. Ureter

  4. Urethra

Show answer
Correct Option: D
Explanation:

a) Nephrons are structures located in the kidney which help in filteration of blood to form urine. 

b) Glomerulus are a part of nephrons and are located in kidneys. 
c) Ureters carry urine from kidneys to urinary bladder. 
d) Urethra carries urine from urinary bladder to the outside.
So, the correct answer is option 'Urethra'.

Average quantity of urea excreted daily humans per day is

evs - i excretion in living organisms other systems in the body excretory system in human human excretory organs

  1. 10 - 15 g

  2. 25 - 30 g

  3. 40 - 50 g

  4. 100 - 500 mg

Show answer
Correct Option: B
Explanation:

The composition of urine in humans is 95% water, 2.5 % urea and 2.5% other waste. As urea is the major excretory waste humans are considered ureotelic., On an average, 25-30 g of urea is excreted out per day.

So, the correct answer is '25-30 g'.

The composition of urine is

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

  1. 25% water, 2.5 % urea and 2.5% other waste

  2. 95% water, 2.5 % urea and 2.5% other waste

  3. 95% water, 2.5 % urea and 12.5% other waste

  4. None of the above

Show answer
Correct Option: B
Explanation:
An adult human on an average excretes 1 to 1.5 liters of urine per day. It is light yellow in color, slightly acidic with a characteristic odor. The composition of urine is 95% water, 2.5 % urea and 2.5% other waste. As urea is the major excretory waste humans are considered ureotelic.
So, the correct answer is '95% water, 2.5 % urea and 2.5% other waste'.

The conduction of urine from kidney to the urinary bladder takes place by

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

  1. Ureter

  2. Urethra

  3. Ovary

  4. None of the above

Show answer
Correct Option: A
Explanation:

Urine is formed in the kidney. From the kidneys, two tubes called ureter one from each kidney descend to the urinary bladder which conducts urine from the kidneys to the urinary bladder. Urinary bladder receives and stores urine. Later, on stimulus urine is excreted to outside through urethra.

So, the correct answer is 'Ureter'.

The tubes which connect the kidney and urinary bladder is known as

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

  1. Ureter

  2. Kidney

  3. Urethra

  4. None of the above

Show answer
Correct Option: A
Explanation:
The tubes which connect the kidney and urinary bladder are known as the ureter. Urine is formed in the kidney. From the kidney, urine is propelled into the urinary bladder through the tubes called ureters which are made of smooth muscle fibres.
So, the correct answer is 'Ureter'.

Choose the correct answers from the following given.
Which of the following is not an excretory organ?

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

  1. Spleen

  2. Kidney

  3. Liver

  4. Lungs

Show answer
Correct Option: A
Explanation:

Although kidney is the main organs of excretion, several other organs also excrete wastes. They include the liver, skin, and lungs.  Excretory system of a human consists of kidneys, ureters, urinary bladder, and urethra.

So the correct answer is spleen.