Question

Whale is air breather but can live underwater for a long time because it possesses
A. Rete mirabile
B. Small lungs
C. Blubber
D. None of the above

Answer 1

Hint: Whales are a group of aquatic mammals. They are an informal group of organisms in the phylum chordata and this group generally does not include dolphins and porpoises.

Complete Answer:
Whales being aquatic organisms have evolved lungs which enables them to breathe the air in the atmosphere. These organisms do not have gills for breathing underwater. Still, these organisms can stay inside water for a very long time without having to breathe in air frequently. This is facilitated by a complex of arteries and veins which provide a bypass such that whales can isolate skeletal muscle circulation when diving and can use the oxygen remaining in the blood to maintain the heart and lungs, thereby preventing suffocation due to their inability to breathe underwater.

Now, let us look at each option one by one.
- The Rete Mirabile is the complex of arteries and veins which help in maintaining the circulation of oxygen to the heart and brain when the whale is underwater. Therefore, this is the correct option.
- Whales breathe with the help of lungs. Since these aquatic mammals are humongous in size, there is no chance that they possess small lungs. They have a pair of lungs that is in proportion to the amount of oxygen required by their body. Therefore, this option is incorrect.
- Blubber is the thick layer of fat (adipose tissue) present under the skin of all cetaceans, pinnipeds, sphenisciformes, and sirenians such as sharks and whales. Blubber does not help with respiration. Therefore, this option is incorrect.
- Since the correct answer for the question is Rete mirabile, none of the above cannot be the solution. Therefore, this option is incorrect.

Thus, the correct answer to this question is (A) Rete Mirabile.

Note: Whales are the largest mammals living on Earth and they can be found in all the oceans throughout the globe. The colossal blue whale is the largest amongst the whales and can weigh upto 200 tonnes (200,000 kilograms) and stretches up to 100 feet long (almost the same length as a professional basketball court).