NCERT Exercise - Q1
Textbook Exercise Problem
What is a habitat? Name its two primary components.
Step-by-Step Verified Solution:
- Step 1: Define habitat: The surrounding environment where an organism lives, feeds, reproduces, and survives is called its habitat.
- Step 2: Identify components: (i) Biotic components (living things like plants, animals, microbes), (ii) Abiotic components (non-living things like rocks, soil, air, water, sunlight).
Final Answer: Habitat is the dwelling place of an organism, consisting of Biotic and Abiotic components.
Key Concept / Exam Strategy: Adaptation is an evolutionary response to the abiotic conditions of the habitat.
Generated Exercise #1
Foundation
Question: How is a cactus adapted to survive in desert conditions?
Core Concept Tested: Xerophytic adaptations in desert plants
Mentor Hint: Think about leaves, stems, and roots.
Step-by-Step Solution:
- Step 1: Leaves are modified into spines to reduce water loss via transpiration.
- Step 2: Stem is green, fleshy, and performs photosynthesis while storing water.
- Step 3: Stems are coated with a thick waxy layer to retain moisture.
- Step 4: Roots penetrate deep into the ground to absorb water.
Verified Answer: Spine-modified leaves, green fleshy photosynthetic stem with waxy layer, and deep roots.
Generated Exercise #2
Intermediate
Question: Differentiate between respiration and breathing with one clear scientific distinction.
Core Concept Tested: Biological mechanisms of cellular respiration vs gas exchange
Mentor Hint: Breathing is physical; respiration is biochemical.
Step-by-Step Solution:
- Step 1: Breathing is a physical process of inhaling oxygen and exhaling carbon dioxide.
- Step 2: Respiration is a biochemical cellular process where glucose is broken down to release energy (ATP).
Verified Answer: Breathing is physical gas exchange; respiration is cellular biochemical energy production.
Generated Exercise #3
Intermediate
Question: Why do fishes die when taken out of water even though air contains more oxygen than water?
Core Concept Tested: Gill morphology and dissolved oxygen absorption
Mentor Hint: Gills need water to keep gill filaments separated and moist.
Step-by-Step Solution:
- Step 1: Fishes possess gills equipped with fine filaments that absorb oxygen dissolved in water.
- Step 2: In air, the fine gill filaments stick together due to surface tension, collapsing the surface area.
- Step 3: The fish is unable to absorb gaseous oxygen from air and dies of asphyxiation.
Verified Answer: Gill filaments collapse and stick together in air, reducing surface area so they cannot absorb atmospheric oxygen.
Generated Exercise #4
JEE-NEET Foundation
Question: Name the process by which plants release water vapor into the atmosphere. How does humidity affect this rate?
Core Concept Tested: Transpiration mechanism and environmental rate dependencies
Mentor Hint: Higher ambient humidity reduces the water vapor gradient.
Step-by-Step Solution:
- Step 1: The process is called Transpiration (loss of water vapor through stomata).
- Step 2: Rate of transpiration is inversely proportional to relative humidity.
- Step 3: When humidity is high, the air already contains excess water vapor, reducing the rate of transpiration.
Verified Answer: Transpiration. High humidity decreases transpiration rate.
Generated Exercise #5
Advanced HOTS
Question: A touch-me-not (Mimosa pudica) plant rapidly folds its leaves upon being touched. Identify: (a) Stimulus, (b) Response, (c) Life characteristic demonstrated.
Core Concept Tested: Nastic movement and responsiveness to stimuli in botany
Mentor Hint: The touch is the external trigger; folding is the action.
Step-by-Step Solution:
- Step 1: Stimulus = Physical touch / mechanical contact.
- Step 2: Response = Rapid folding and drooping of leaflets caused by turgor pressure changes.
- Step 3: Life Characteristic = Response to stimuli (Irritability / Sensitivity).
Verified Answer: (a) Physical touch, (b) Rapid leaf folding, (c) Response to external stimuli