Tag: excretion - plants

Questions Related to excretion - plants

Which of the following is the most toxic excretory product?

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

  1. $CO _2$

  2. Ammonia

  3. Urea

  4. Amino acids

Show answer
Correct Option: B
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).

Which of the following pairs is wrong? 

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

  1. Uricotelic - Birds

  2. Ureotelic - Insects

  3. Ammonotelic - Tadpole

  4. Ureotelic - Elephant

Show answer
Correct Option: B
Explanation:

Insects are uricotelic i.e, they excrete uric acid. 

Which one of the following statements is incorrect? 

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

  1. Birds and land snails are uricotelic animals.

  2. Mammals and frogs are ureotelic animals.

  3. Aquatic amphibians and aquatic insects are ammonotelic animals.

  4. Birds and reptiles are urotelic

Show answer
Correct Option: D
Explanation:

In Uricotelic organisms, the end product of nitrogen metabolism is uric acid.  include terrestrial arthropods (including insects), lizards, snakes, and birds. 

So, the correct option is 'Birds and reptiles are urotelic'. 

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

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

  1. Urea

  2. Uric acid

  3. Ammonia

  4. Carbon dioxide

Show answer
Correct Option: B
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.

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.

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

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

  2. (i) only

  3. (i) and (iii)

  4. (i) and (iv)

Show answer
Correct Option: B
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'.

Arrange the following in correct order based on increasing toxicity.

(a) Urea
(b) Uric acid
(c) Ammonia

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

  1. a-b-c

  2. b-a-c

  3. c-a-b

  4. c-b-a

Show answer
Correct Option: B
Explanation:

Nitrogenous waste that is produced in the body needs to be excreted from the body as they are toxic to an organism. The waste is excreted in 3 forms, namely ammonia, uric acid, and urea. Ammonia is more water-soluble and most toxic. It requires less energy for excretion. Animals excreting nitrogenous waste in the form of ammonia are called as ammonotelic. Aquatic animals like protozoans, crustaceans, poriferans, fishes where water is not a constraint are ammonotelic. Urea requires comparatively more energy and is less toxic in nature. Animals excreting nitrogenous waste in the form of urea are called as ureotelic. Examples include cartilaginous fish, amphibians, mammals including humans. Uric acid is least soluble in water and is least toxic. However, it requires a large amount of energy. Examples include reptiles, birds.

Thus, the correct answer is 'b-a-c.'

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

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

  1. Carbon dioxide

  2. Mineral salts

  3. Bile pigments

  4. Urea

Show answer
Correct Option: B
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).

What is the first excretory substance in animal body?

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

  1. Urea

  2. Ammonia

  3. Amino acid

  4. Uric acid

Show answer
Correct Option: B
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'.

Which living organism is not a uricotelic?

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

  1. Insects

  2. Birds

  3. Crocodile

  4. Alsatian dog

Show answer
Correct Option: D
Explanation:
A) Insects are uricotelic.
B) Birds are uricotelic.
C) Crocodiles and all reptiles are uricotelic.
D) The Alsatian dog is a mammal. Mammals are ureotelic (excrete urea).
So the correct answer is 'Alsheshan dog'.

Animals return water to the environment by
(i) Perspiring
(ii) Drinking
(iii) Urinating
(iv) Breathing

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

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

  2. (i) and (ii)

  3. (i) and (iii)

  4. (iii) and (iv)

Show answer
Correct Option: A
Explanation:

A) Perspiration (sweating) is the loss of water and salts through the surface of the skin. This water evaporates. Urine is mostly water and is also composed of salts and is excreted by the animal into the environment. While breathing, minute molecules of water or water vapour are given out into the environment along with carbon dioxide.

B) While drinking water, the animal consumes it from the environment.
C) Perspiration and urination release water into the environment.
D) Breathing releases water in form of water vapour into the environment.
So, the correct answer is '(i), (iii) and (iv)'.