Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Habitat: The surroundings where organisms live is called a habitat. It provides food, water, air, shelter, and other needs. A habitat consists of Biotic components (living things like plants and animals) and Abiotic components (non-living things like rocks, soil, air, water, sunlight, and temperature).
Adaptation: The presence of specific features or certain habits which enable a plant or an animal to live in its surroundings is called adaptation. For example, camels have long legs to keep their bodies away from the heat of the sand.
Terrestrial Habitats: These are habitats on land. Examples include Deserts (hot and dry), Mountains (cold and windy), and Grasslands. In deserts, plants like cacti have leaves reduced to spines to prevent water loss via transpiration, and photosynthesis is carried out by the stems.
Aquatic Habitats: These are habitats in water. Examples include Oceans, Ponds, and Lakes. Fish have streamlined bodies to reduce friction in water and gills to absorb dissolved oxygen ().
Acclimatization: Small changes that take place in the body of a single organism over short periods to overcome small problems due to changes in the surroundings are called acclimatization. This is different from adaptation, which occurs over thousands of years.
Characteristics of Living Beings: All living things require food, show growth, respire, respond to stimuli, excrete, reproduce, and show movement. Respiration is the process where the body uses oxygen () to obtain energy from food, releasing carbon dioxide ().
📐Formulae
💡Examples
Problem 1:
A scientist measures the water loss (transpiration) from two plants over hours. Plant A (a rose) loses of water. Plant B (a cactus) loses only of the water lost by Plant A. Calculate the water lost by the cactus.
Solution:
Water lost by Plant B = of
Explanation:
Cacti are adapted to desert environments. They have a thick waxy coating on their stems and their leaves are reduced to spines to minimize water loss through transpiration.
Problem 2:
Identify the biotic and abiotic components in the following list: Fish, Water, Sunlight, Water Lily, Sand, Crab.
Solution:
Biotic: Fish, Water Lily, Crab. Abiotic: Water, Sunlight, Sand.
Explanation:
Biotic components are living organisms, while abiotic components are the non-living physical and chemical factors in the environment.
Problem 3:
How does the breathing process of a whale differ from a fish?
Solution:
Fish use gills to breathe oxygen dissolved in water, whereas whales use blowholes (nostrils) located on the upper parts of their heads to breathe air from the atmosphere.
Explanation:
Whales are mammals and do not have gills. They come up to the water surface to take in air () through their blowholes and can stay inside the water for a long time without breathing.