Different Types of Plants for Class 3 Science
- Plants are ultimate producers hence the essential part of the food chain.
- Different types of plants can be seen growing in different habitats and soils.
- The plant body can be divided into a shoot system (above the ground) and a root system (below the ground).
- Different plant parts are used for a variety of purposes.
- Plants require sunlight, water, minerals, and carbon dioxide to grow and develop.
How Do Plants Grow
Question 1:
Why Do Cactus Have Spines Instead of Leaves?
Answer:
- Cacti grow on land where very little or no water is available throughout the year.
- The rate of evaporation from the plant depends on the size of the leaves.
- So, to reduce water loss, cacti leaves are converted into spines.
Question 2:
How to Find Out Whether the Plant Is Dead or Alive When No Leaves or Flowers Are on It?
Answer:
- Plants shed their leaves to dispose of the waste material.
- The absence of leaves on a plant is not a sign of a dead plant.
- If the plant's stem is green or brownish, then the plant redevelops leaves and shoots.
- The plant is considered dead when the stem turns black and dries completely.
Question 3:
How Do the Roots Protect Themselves While Growing Through the Soil?
Answer:
- The roots of plants are delicate and grow to penetrate deep into the soil.
- A group of dead cells protects the tip of the root called the root cap.
- The root cap protects the part of the root behind it.
Question 4:
Why Do New Leaves and Buds Arise From Specific Points on the Stem?
Answer:
- New leaves and buds arise only from the points where the nodes are located on the stem.
- The area on nodes shows high cellular activity, which helps develop buds, flowers, leaves, branches, etc.
Question 5:
Name the Stems Used by Humans.
Answer:
- The stem of sandalwood is used to make lotions and other cosmetics for fragrance.
- The stem of sugarcane and Date plants are used to make sugar.
- Bamboo shoots, potato tubers and ginger rhizomes are used as food ingredients.
Different Kinds of Plants
Question 1:
Why does the Freshly Cut Grass Smell Differently?
Answer:
- The smell from the freshly cut grass blades is a mixture of different chemical compounds.
- The release of these chemicals is a reaction of plants towards cutting. These chemicals keep the bacteria and bugs away from the plants.
Question 2:
Where Are Mangroves Found?
Answer:
- Mangroves grow in salty and Muddy water along the coast.
- The complex salt filtration system and the root system of mangrove plants enable them to survive in saltwater.
- They are adapted to survive in low-oxygen soil due to water-logged conditions.
What Do Plants Need to Grow?
Question 1:
Why Do Different Plants Bloom at Different Periods? Where Are Mangroves Found?
Answer:
Different plants bloom at different periods due to the following reasons:
- Some plants need less sunlight, whereas some need more. Based on the duration of sunlight, they bloom at different times.
- Some plants depend on nocturnal insects for pollination; hence they bloom during the night to aid the pollination. Night-blooming jasmine is an example.
Question 2:
Do Plants Need Oxygen? How Do They Get It?
Answer:
Different plants bloom at different periods due to the following reasons:
- Yes, like animals' plants also need oxygen. They absorb it through stomata in leaves and lenticels in the stem.
- The roots of the plants are also capable of absorbing dissolved oxygen from the water in the soil.
