Tag: structures and functions related to the excretory system

Questions Related to structures and functions related to the excretory system

In birds, excretion of nitrogenous wastes, mainly as uric acid, is helpful for

  1. eliminating excess body water

  2. conserving body water

  3. eliminating excess body heat

  4. eliminating excess sugar


Correct Option: B
Explanation:

Birds excrete nitrogenous wastes as uric acid in the form of a pellet or paste with a minimum loss of water. Therefore they are called uricotelic animals. 

So the correct option is conserving body water. 

Choose the correct answers from the following given.
Ammonia is excreted by most

  1. bony fishes

  2. adult amphibians

  3. land snails

  4. insects


Correct Option: A
Explanation:

(A) The process of excreting ammonia is Ammonotelism. Many bony fishes, aquatic amphibians and aquatic insects are ammonotelic. 

(B) Mammals, many terrestrial amphibians and marine fishes mainly excrete urea and are called ureotelic animals.
(C) land snails excrete nitrogenous wastes as uric acid in the form of a pellet.
(D) insects excrete nitrogenous wastes as uric acid in the form of a pellet or paste with a minimum loss of water and are called uricotelic animals.
So the correct answer is bony fishes.

Choose the wrong statement.

  1. In ureotelic organisms, ammonia is not a product metabolism

  2. In mammals some amount of urea may be retained in the kidney matrix of ureotelics of maintain osmolarity

  3. In fishes, kidneys do not play any significant role in the removal of ammonium ions

  4. Urea and uric acid less toxic than ammonia


Correct Option: A

Which one of the following statements is incorrect?

  1. In cockroaches and prawns excretion of waste material occurs through Malpighian tubules

  2. In ctenophores, locomotion is mediated by comb plates

  3. In Fasciola flame cells take part in excretion

  4. Earthworm are hermaphrodites and yet cross fertilization take place among them


Correct Option: A
Explanation:

Malpighian tubules are excretory structures in most insects, including cockroaches, but in crustaceans such as prawns, green glands conduct excretory functions, whereas all other statements are true.

Which cutaneous gland of pigeon produces 'pigeon milk'?

  1. Uropygeal

  2. Preen

  3. It is not produced by cutaneous but the crop gland

  4. None of the above


Correct Option: C
Explanation:

Crop milk is a secretion from the lining of the crop of parent birds that is regurgitated to young birds. They are found among all pigeons and doves, where they are referred to as pigeon milk. Crop milk is also produced by flamingos and some penguins.

The deep sea organisms having luminous or phosphorescent organ in their integument are

  1. Amphibians

  2. Fish

  3. Mammals

  4. All of the above


Correct Option: B
Explanation:

Bioluminescence is the production and emission of light by a living organism. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some bioluminescent bacteria and terrestrial invertebrates such as fireflies. 

Dermal scales are present in

  1. Anura

  2. Urodela

  3. Labyrinthodontia

  4. Gymnophiona


Correct Option: D
Explanation:

Gymnophiona, also called apoda, is one of the three major extant orders of the class amphibia. Its members are known as caecilians. Their skin is smooth but some species have colourful skins. Inside the skin are calcite scales. Because of these scales, the caecilians were once thought to be related to the fossil Stegocephalia.

Renal gland is the excretory organ of

  1. Annelida

  2. Echinodermata

  3. Crustaceans

  4. Mollusca


Correct Option: D
Explanation:

The renal gland is a relatively wide tube opening from a sac (the pericardium) surrounding the heart, at one end, and to the mantle cavity (effectively to the exterior) at the other. The anatomical form of the renal gland varies from one class of molluscs to another.

Marcello Malpighi in 1966 first described

  1. Nephron

  2. Glomerulus

  3. Bowman's capsule

  4. Pygmalion corpuscles


Correct Option: D
Explanation:

The Bowman's capsule and the glomerulus together constitute the malpighian corpuscle (pygmalion corpuscle or renal corpuscle). The malphigian corpuscles were first described by Morcello Malpighi in the year 1966.

Urinary bladder is not found in 

  1. Snakes

  2. Crocodiles

  3. Birds

  4. All of the above


Correct Option: D
Explanation:

Birds and reptiles urinate in a way to conserve their water. Unlike mammals, which excrete waste fluid as urine and solid waste as faeces, birds and reptiles mix both liquid waste and solid waste into the semi-solid paste (nitrogen containing waste) formed from the breakdown of proteins. Hence snakes, crocodiles, birds and most lizards lack a urinary bladder.