1.Why Do Cactus Have Spines Instead of Leaves?
- 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.
![Cactus](https://cdn-cms.orchidsinternationalschool.com/media/answer/G3_2_Alt-Text-Desert-plants-1.jpg)
2. How to Find Out Whether the Plant Is Dead or Alive When No Leaves or Flowers Are on It?
- 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.
![dead plant](https://cdn-cms.orchidsinternationalschool.com/media/answer/G3_3_Alt-Text-Desert-plants-1.jpg)
3. How Do the Roots Protect Themselves While Growing Through the Soil?
- 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.
4. Why Do New Leaves and Buds Arise From Specific Points on the Stem?
- 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.
![Leaves and Buds](https://cdn-cms.orchidsinternationalschool.com/media/answer/G3_4_Alt-Text-Nodes-and-internodes.jpg)
5. Name the Stems Used by Humans.
- 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.
![Stems Used by Humans](https://cdn-cms.orchidsinternationalschool.com/media/answer/G3_5_Alt-Text-useful-stems-1.jpg)