Adaptation

Desert plants typically exhibit adaptations such as thick cuticles (A) to reduce water loss, spine-like leaves (B) to minimize surface area and deter herbivores, and sunken stomata (C) to trap humid air and reduce transpiration. Trichomes (hair-like structures) are actually beneficial in arid environments—they reflect sunlight, reduce air flow over stomata, and sometimes secrete protective compounds.

Their absence (D) would deprive plants of these advantages, making this feature non-adaptive for desert survival.

Thus, (D) is the exception among the listed traits.

The correct answer is (D) Absence of trichomes on leaf surface.

Let's evaluate each statement:

CAM plants close their stomata during the daytime:

• This statement is correct. CAM (Crassulacean Acid Metabolism) plants, like succulents, open their stomata at night to minimize water loss and perform carbon fixation, and they keep their stomata closed during the day to conserve water.

Seals have a thick layer of fat to reduce body heat:

• This statement is incorrect. Seals have a thick layer of fat (blubber) to insulate their bodies and retain heat, not to reduce body heat. This adaptation helps them survive in cold marine environments.

Lizards bask in the sun during winter:

• This statement is correct. Lizards, being cold-blooded, need external heat sources to regulate their body temperature. During colder months, they bask in the sun to warm up.

Tribes living in high altitudes have the same RBC count as people living in the plains:

• This statement is incorrect. People living at high altitudes typically have a higher RBC (red blood cell) count compared to those living in plains. This is due to the lower oxygen levels at higher altitudes, which stimulate the production of more red blood cells to increase oxygen-carrying capacity.

The incorrect statements are B and D.

The correct answer is both (B) : Seals have a thick layer of fat to reduce body heat and (D) : tribes living in high altitude have the same RBC count as people living in the plains.