Science
How many chambers are there in the heart of the following organisms? How is mixing of oxygenated and deoxygenated blood prevented in their body?
(a) Fishes
(b) Humans
Answer
(a) Fishes have a two-chambered heart.
Their heart pumps only deoxygenated blood to the gills. Oxygenated blood from gills goes straight to the body without re-entering the heart. This prevents mixing of oxygenated and de-oxygenated blood.
(b) Humans have a four-chambered heart.
Right (deoxygenated) and left (oxygenated) sides are separated by the septum, with one-way valves keeping flows apart preventing mixing of oxygenated and de-oxygenated blood.
Related Questions
Assertion (A) : Vulture will always have the least amount of pesticides in a food chain.
Reason (R) : Vulture occupies the last trophic level and it gets only 10% of energy of the previous trophic level.
options
- Both A and R are true, and R is the correct explanation of A.
- Both A and R are true, and R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
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