PSEB solutions class 7 science chapter 1
Fill in the blanks answers
- Nutrition
- Carbon dioxide
- Glucose
- Heterotrophs
State true or false
- False
- True
- True
- False
Match the following
Agaricus saprophyte
Rhizobium – leguminous plants
Chlorophyll – leaves
Cuscuta – parasite
Choose the correct option:
- An Organism ……………… nitrogen in the soil is:
- Rhizobium
- The Organisms that ……………….. and depends on others for food are known as:
- Heterotrophs
- The food ……………… plants is:
- Leaf
- Which of ……………….. is a saprophyte?
- Cuscuta
Short answer type question:
- Define Nutrition.
- Nutrition is the process by which an organism obtains and utilizes food.
- What is photosynthesis?
- The photosynthesis process involves green plants preparing their food using chlorophyll in the presence of CO2, water, and sunlight.Green plants convert light energy into chemical energy.
- Name the raw materials required for photosynthesis.
- Carbon dioxide and water
- What are insectivorous plants?
- Plants that consume insects have structures that trap and digest insects are known as insectivorous plants.
Short answer type question:
- What do you mean by parasitic mode of nutrition?
- Nutrition in which the organism derives its food from other organisms is called parasitic nutrition.
- Explain symbiotic relationship.
- In a symbiotic relationship, two types of organisms live together and share shelter and nutrients. As a result, both organisms benefit from each other. A lichen is a good example.
- How does a pitcher plant catch insects?
- The leaves of pitcher plants are modified as pitcher-shaped bodies to trap the insects. Whenever an insect sits on the opening of the pitcher, it slips down, is unable to climb back, and becomes trapped.
Long answer type questions:
- How are nutrients …………….in the soil?
- Plants absorb minerals, water, and nutrients from the soil and these nutrients must be replenished to keep the soil fertile. Farms enrich soil by adding manure and fertilizers, while forests enrich soil by decomposing dead leaves and animal matter.
- What do you mean by nutrients? explain various modes of nutrition in plants.
The main nutrients in food are carbohydrates, fats, proteins, vitamins, and minerals.
An organism that makes its food from simple substances is called an autotroph and this type of nutrition is called autotrophic nutrition. Autotrophs include all green plants and some bacteria.
Heterotrophic nutrition
Organisms that cannot prepare their own food and rely on others for food are heterotrophs, and this type of nutrition is called heterotrophic nutrition. Examples are Animals and few plants .
Points to Remember
The initial products of photosynthesis are oxygen gas and glucose.
Stomata are surrounded by guard cells.
