Question

Explain the given characteristics in each types of animals
1. Excretory matter
2. Requirement of water
3. Mechanism of excretion
4. Toxicity
Also give two two exanples of each​

Answer 1

Animals on the basis of excretory matter are divided into three categories

a. Ammonotelic

1. Excretory Matter- Ammonia

2. Requirement of water- Very large amount of water is required.

3. Mechanism of excretion- Process occurs through the diffusion across the surface of body and even through gills in animals like fishes as ammonium ion.

4. Toxicity- It's very high and Highest in comparison to all.

Examples-

(i) Tadpoles

(ii) Aquatic insects etc.

b. Ureotelic

1. Excretory Matter- Urea

2. Requirement of water- Less than Ammonia

3. Mechanism of excretion- Ammonia which is produced by the metabolism can converts into the urea in the liviand then is released into the blood for filtration and then is excreted outside by the help of kidneys.

4. Toxicity- Less than Ammonia.

Examples-

(i) Mammals

(ii) Sharks etc.

c. Uricotelic

1. Excretory Matter- Uric acid

2. Requirement of water- Least

3. Mechanism of excretion- No any specialised mechanism occurs.

4. Toxicity- Least

Examples-

(i) Birds

(ii) Land snails

(iii) Insects etc

Answer 2

Answer:

I) Ammonotelism :

=> Elimination of nitrogenous waste in the form of ammonia.

=> Organisms which excrete ammonia as main excretory product are Ammonotelic.

=> About 300 to 500 ml of water is required for elimination of 1 g of ammonia.

=> Occurs through diffusion.

=> Ammonia is highly toxic.

Example : Bony fishes, tadpole, larva of frog.

Ureotelism :

=> Elimination of nitrogenous waste in the form of urea.

=> Ureotelic organisms.

=> 50 ml of water is required for elimination of 1 g of urea.

=> Occurs through ornithine cycle.

=> Urea is less toxic than ammonia .

Example : Frog, turtles, toads, mammals, marine fishes.

Uricotelism :

=> Elimination of nitrogenous waste in the form of uric acid.

=> Uricotelic organisms.

=> About 10 ml of water is required for elimination of 1 g of uric acid.

=> Occurs through inosinic pathway.

=> Uric acid is least toxic.

Example : Snails, reptiles, birds, terrestrial insects, lizards, snakes.