DAV Class 4 Science Chapter 4: Plants Around Us – Complete Question Answers
Introduction
Plants are found in different places around us. Some plants grow on hills, some on plains, some in deserts, and some in water. Plants develop special features according to the surroundings in which they grow.
In this chapter, we learn about terrestrial plants, aquatic plants, plants of hills, plains and deserts, breathing roots, cultivated plants, weeds, and different plant habitats.
Below are the complete solved questions and answers for DAV Class 4 Science Chapter 4 – Plants Around Us.
Something to Know
A. Fill in the Blanks
1. Plants, growing on hills, are tall, straight and have a _______ shape.
Answer: Conical
Plants growing on hills are generally tall and straight and have a conical shape.
2. _______ and _______ are two of the trees that grow on plains.
Answer: Neem and banyan
Neem and banyan are two common trees that grow on plains.
3. Breathing roots are also called _______ roots.
Answer: Aerial
Breathing roots are also called aerial roots because they come out of the soil and help the plant get oxygen.
4. _______ is an underwater plant.
Answer: Hydrilla
Hydrilla is an underwater plant that grows completely under water.
5. Lotus stem is eaten as a _______.
Answer: Vegetable
The stem of the lotus is eaten as a vegetable.
B. Match the Following
| Column A | Column B |
|---|---|
| 1. Evergreen trees | (e) Rubber and teak |
| 2. Needle-like leaves | (f) Pine and cedar |
| 3. No leaves | (b) Cactus |
| 4. Breathing roots | (c) Mangrove |
| 5. Air-filled cavities | (d) Aquatic plant |
| 6. A cultivated crop | (a) Rice |
Answers
- Evergreen trees — Rubber and teak
- Needle-like leaves — Pine and cedar
- No leaves — Cactus
- Breathing roots — Mangrove
- Air-filled cavities — Aquatic plant
- A cultivated crop — Rice
C. Tick (✓) the Correct Option
1. It is a free-floating plant.
(a) Water hyacinth ✓
(b) Hydrilla
(c) Coconut
(d) Lotus
Answer: (a) Water hyacinth
Water hyacinth is a free-floating aquatic plant.
2. These are unwanted plants.
(a) Cactus
(b) Grass
(c) Mangroves
(d) Weeds ✓
Answer: (d) Weeds
Weeds are unwanted plants that grow along with crops in fields.
3. It can survive in soil with very little water.
(a) Banyan
(b) Teak
(c) Rubber
(d) Cactus ✓
Answer: (d) Cactus
Cactus can survive in desert conditions where there is very little water.
D. Answer the Following Questions in Brief
1. What are terrestrial plants?
Answer:
Plants which grow on land are called terrestrial plants.
2. How does the conical shape help the plants of hills?
Answer:
The conical shape prevents the accumulation of snow on the leaves. Thus, the plants are protected from damage.
3. Name two trees growing in hot and wet regions.
Answer:
Teak and rubber are two trees that grow in hot and wet regions.
4. Name an underwater plant. What kind of leaves does it have?
Answer:
Hydrilla is an underwater plant. It has ribbon-shaped leaves.
5. What is ploughing?
Answer:
Digging and loosening the soil is called ploughing.
E. Answer the Following Questions
1. List different habitats of terrestrial plants.
Answer:
The different habitats of terrestrial plants are:
- Hills
- Plains
- Deserts
2. How is cactus plant able to grow in desert conditions?
Answer:
Cactus plants have well-developed roots that can go deep into the ground. Their green stems can perform the function of leaves. The leaves are fleshy and store water. The leaves have changed into spines.
These special features help cactus plants survive and grow in desert conditions.
3. What are aquatic plants? State their types and give two examples of each type.
Answer:
Plants which grow in water are called aquatic plants.
There are two main types of aquatic plants:
(a) Floating Aquatic Plants
Floating aquatic plants are of two types:
1. Free-floating plants:
These plants are not attached to any surface. Their leaves have air-filled cavities that help them float on water.
Examples: Water lettuce and water hyacinth.
2. Fixed aquatic plants:
These plants are fixed to the bottom of the water body with their roots. Their stems are very long and have holes in them. Their leaves are very broad.
Examples: Lotus and water lily.
The stem of lotus, called kamal kakri, is eaten as a vegetable.
(b) Underwater Plants
Underwater plants grow completely under water. They have ribbon-like leaves.
Example: Hydrilla.
4. What are cultivated plants?
Answer:
When a plant is grown by human beings for any use, it is called a cultivated plant.
Human beings grow plants such as rice, wheat, maize and cotton on a large scale.
5. Why should weeds be removed from the fields?
Answer:
Weeds should be removed from the fields because they consume water and fertilizers meant for the crops. Thus, weeds are harmful to crops and need to be removed.
Give Reasons
1. Plants growing on hills have a conical shape. Give reason.
Answer:
Plants growing on hills have a conical shape because this shape prevents snow from accumulating on their leaves. This protects the plants from damage.
2. Cactus can survive in desert conditions. Give reason.
Answer:
Cactus can survive in deserts because it has special features such as deep roots, a green stem and fleshy parts that store water. Its leaves are changed into spines.
3. Mangrove plants have breathing roots. Give reason.
Answer:
Mangrove plants grow in marshy areas where their roots may not get sufficient oxygen. Their breathing roots come out of the soil and help them get oxygen.
4. Weeds should be removed from fields. Give reason.
Answer:
Weeds should be removed because they use the water and fertilizers needed by crops. Therefore, they can harm the growth of crops.
5. Some aquatic plants can float on water. Give reason.
Answer:
Some aquatic plants have air-filled cavities in their leaves. These cavities help the plants float on water.
Value-Based Questions
1. How do we know that Ramesh is a very caring boy?
Answer:
Ramesh felt very sad when he saw his grandfather in the fields. He talked to his father about the problems. This shows that Ramesh is a very caring boy.
2. What kind of man is Ramesh’s father?
Answer:
Ramesh’s father is also a caring person.
3. How can you help your grandparents?
Answer:
We can help our grandparents in the following ways:
- We can read the newspaper for them.
- We can help them during their morning walk.
- We can fetch things for them.
- We can bring medicines for them.
Something to Do
1. Observe the roots of grass and mustard plants.
Take a small sapling of grass and a mustard plant. Observe their roots and note down the differences.
Answer:
The mustard plant has a tap root, while grass has fibrous roots.
2. Prepare a chart showing some edible roots and the ways in which they are eaten.
Answer:
| Edible Root | Way of Eating |
|---|---|
| Carrot | Raw and cooked |
| Radish | Raw and cooked |
| Beetroot | Raw and cooked |
| Sweet potato | Cooked |
Important Points to Remember
- Plants that grow on land are called terrestrial plants.
- Plants that grow in water are called aquatic plants.
- Hills, plains and deserts are different habitats of terrestrial plants.
- Plants growing on hills generally have a conical shape.
- Neem and banyan are trees that grow on plains.
- Cactus can survive with very little water.
- Breathing roots are also called aerial roots.
- Mangrove plants have breathing roots.
- Hydrilla is an underwater plant.
- Hydrilla has ribbon-shaped leaves.
- Water hyacinth is a free-floating plant.
- Lotus and water lily are fixed aquatic plants.
- Aquatic plants may have air-filled cavities that help them float.
- Plants grown by human beings for any use are called cultivated plants.
- Rice, wheat, maize and cotton are cultivated plants.
- Weeds are unwanted plants that grow along with crops.
- Ploughing means digging and loosening the soil.
- Weeds should be removed because they use water and fertilizers needed by crops.
Conclusion
Plants grow in different habitats and develop special features according to their surroundings. Plants growing on hills, plains, deserts and water have different characteristics that help them survive.
By learning about terrestrial plants, aquatic plants, cactus, mangroves, cultivated plants and weeds, students can understand how plants adapt to different environments.
We should take care of plants and protect our environment because plants are an essential part of life.
