CBSE Class 6 Science Exemplar NCERT Solutions: Chapter 9 - The Living Organisms and their Surroundings

Solution: (d): Cultivated land with grazing cattle.

A habitat is defined as the natural environment where a specific organism lives. This environment must provide all the essential elements for survival, including food, shelter, and appropriate climatic conditions. Cultivated land, which is managed and altered by humans for agriculture, does not represent the natural, undisturbed environment that typically defines a habitat for wild or grazing animals.

Solution: (d): (iii) and (iv)

Desert plants are adapted to survive in dry conditions with limited water availability. To conserve water, their leaves are often small or modified into spines, which significantly reduces water loss through transpiration (feature iii). Additionally, their root systems typically grow very deep into the soil to access water sources far below the surface (feature iv). Features (i) and (ii) describe plants that thrive in moist environments and are not characteristic of desert flora.

Solution: (a): Water

An animal with a streamlined and slippery body is typically adapted for life in water. The streamlined shape helps reduce resistance from the water, allowing for efficient movement and swimming. The slippery body surface can further aid in reducing friction and protecting the animal from damage as it moves through the aquatic environment.

Solution: (d): (i), (ii), (iii) and (iv)

All living organisms exhibit several key characteristics necessary for life. These include respiration (the process of releasing energy from food), reproduction (the ability to produce offspring), adaptation (the ability to adjust to their surroundings), and excretion (the removal of waste products from the body). Therefore, all the listed features are indeed characteristics of living beings.

Solution: (a): skin

Earthworms respire through their skin. Their skin is kept moist, which allows for the exchange of gases (oxygen and carbon dioxide) directly with the environment. Earthworms do not possess specialized respiratory organs like gills (used by aquatic animals like fish) or lungs (used by land animals like mammals). Stomata are pores found in plants for gas exchange.

Solution: (d): A chick hatching out of an egg.

A response to a stimulus is an action or change in behavior that occurs as a reaction to an external or internal trigger. Watering of the mouth at the sight of food, the closing of Mimosa leaves upon touch, and shutting our eyes when an object approaches are all examples of responses to stimuli. However, a chick hatching out of an egg is a process of development and reproduction, not a direct reaction to an immediate stimulus.

Solution: The provided source text is incomplete and does not contain the full question or solution for Question 7 regarding respiration in plants. Based on biological principles, plants respire continuously, both day and night, although photosynthesis (which occurs only during the day) produces oxygen and consumes carbon dioxide, while respiration consumes oxygen and produces carbon dioxide.