Question 33 of 33advanced🔍 AnalyzeLong Answer5 marks

Compare the functioning of alveoli in the lungs and nephrons in the kidneys with respect to their structure and functioning.

Correct Answer

Both alveoli and nephrons are structural and functional units designed for exchange processes, but they differ in their specific roles.

Structure: Alveoli are balloon-like structures in the lungs with thin walls containing an extensive network of blood vessels. Similarly, nephrons in the kidneys consist of a cluster of very thin-walled blood capillaries associated with a cup-shaped Bowman's capsule that collects the filtrate. Both structures provide large surface areas for efficient exchange.

Functioning: Alveoli facilitate the exchange of gases. The blood brings carbon dioxide from the body to release into the alveoli, while oxygen from alveolar air is taken up by blood for transport to cells. The lungs retain a residual volume of air to allow sufficient time for this exchange.

Nephrons function as filtration units. They filter blood and produce urine through selective re-absorption of useful substances like glucose, amino acids, salts, and water. The amount of water re-absorbed depends on the body's needs.

Thus, while both structures involve thin walls and blood vessels for exchange, alveoli perform gaseous exchange for respiration, whereas nephrons perform filtration and re-absorption for excretion.

Exercise: EXERCISES | Q: 13 | (Page 21)
For More Understanding

Explanation

The question asks for a comparison between alveoli and nephrons. From the textbook context, alveoli are described as balloon-like structures with thin walls and extensive blood vessel networks for gas exchange. Nephrons are described as filtration units with thin-walled blood capillaries and Bowman's capsule, performing selective re-absorption. The comparison covers both structural similarities (thin walls, blood vessels, large numbers) and functional differences (gas exchange vs filtration/excretion).

Solution Steps

  1. Step 1: Identify structural features of both alveoli and nephrons from context - thin walls, blood vessels, large surface area

  2. Step 2: Identify functional aspects - alveoli for gas exchange, nephrons for filtration and re-absorption

  3. Step 3: Compare similarities (both involve exchange through thin walls with blood vessels)

  4. Step 4: Contrast differences (gaseous exchange vs filtration/excretion)

  5. Step 5: Write comprehensive answer with proper paragraph structure and bold key terms

Previous