Consider the following statements about cactus : 1. The leaves are r

Consider the following statements about cactus :

  • 1. The leaves are reduced to spines.
  • 2. The stem does the photosynthesis.

Which of the statements given above is/are correct ?

1 only
2 only
Both 1 and 2
Neither 1 nor 2
This question was previously asked in
UPSC NDA-2 – 2016
Both statements about cactus adaptations are correct. Cacti are succulents adapted to arid environments. Their leaves are typically reduced to spines to minimize water loss through transpiration and provide defense. The fleshy green stems take over the function of photosynthesis, which is usually carried out by leaves in most plants.
– Statement 1 is correct: Reduction of leaves to spines is a key adaptation of cacti to reduce surface area and thus water loss through transpiration in hot, dry climates. Spines also deter herbivores.
– Statement 2 is correct: Cacti stems contain chlorophyll and are the primary sites of photosynthesis in the absence of significant leaf area. They are also succulent, storing water.
Cacti also have other adaptations for survival in arid environments, such as shallow but extensive root systems to absorb water quickly from rainfall, a waxy cuticle on the stem to reduce evaporation, and CAM photosynthesis, which allows them to keep their stomata closed during the day to conserve water.
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