Plants in the Surroundings and Environment — Important Questions

Carrot, radish, mustard, bean

Step 1: Taproot systems have one main thick root with smaller branches growing out of it. Step 2: Carrot, radish, mustard, and bean all have taproots with a prominent main root. Step 3: Grass, wheat, rice, and onion have fibrous roots – a bunch of thread-like roots of similar size with no main root. Step 4: In Option B, grass and wheat have fibrous roots, so the group is mixed. Step 5: In Options C and D, rice, wheat, grass, and onion all have fibrous roots, making those groups incorrect.

Climber

Step 1: Plants with weak stems need support to grow upright. Step 2: These plants are divided into two groups – creepers and climbers. Step 3: Creepers have weak stems but spread along the ground (e.g., pumpkin, watermelon, strawberry). Step 4: Climbers have weak stems and use walls, sticks, or other structures for vertical support (e.g., money plant, grapevine). Step 5: The question says the plant needs a wall or stick and cannot spread on the ground – this clearly describes a climber, not a creeper. Herbs have soft stems but stand on their own. Bushes have thin, hard stems.

The process of using light energy to put together carbon dioxide and water to make food

Step 1: 'Photo' = light, 'synthesis' = putting together. So photosynthesis literally means 'putting together using light'. Step 2: In this process, plants use light energy (from the Sun) to combine (put together) raw materials. Step 3: The raw materials are carbon dioxide (from air) and water (from soil). Step 4: The output is glucose (food) and oxygen. Step 5: Option A is wrong because oxygen is a product, not a raw material. Option C is wrong as soil and sunlight don't make CO₂. Option D describes respiration (breaking down food), which is the opposite of photosynthesis.

Allow exchange of gases and release of water vapour during transpiration

Step 1: Stomata are tiny openings (pores) found mostly on the undersurface of leaves. Step 2: First function: They allow gases to enter and leave the plant. Carbon dioxide (needed for photosynthesis) enters through stomata, and oxygen (produced during photosynthesis) exits through them. This is called gas exchange. Step 3: Second function: Excess water vapour is released through stomata during transpiration. Step 4: Option A is wrong – stomata do not absorb sunlight (chlorophyll does that) or store food. Step 5: Option C describes the function of roots, not stomata. Stomata are on leaves, not