Class 6th Science Ch 9 The Living Organisms and Their Surroundings

Date 13 December 2022

Day Tuesday

Chapter 9 The living organisms and their surroundings

Keywords

1. adaptation: developing characteristics to survive in the environment

2. habitat A habitat is the natural environment in which an organism lives

3. aquatic habitat: water habitat

4. biotic components: living component of an ecosystem

5. excretion: the process by which an organism eliminates waste materials from its body.

6. Growth: Growth is the process by which an organism increases in size and develops over time

7. Reproduction: It is the process animals produce of their own kind.

 

Answer the following questions in 1-10 words:

Q1. What do you mean by stimulus?

Ans. An external agent which makes our body to response.

Q2. What is respiration?

Ans . It  is the process of inhaling oxygen , release energy and exhaling carbon dioxide by the living organism.

Q3. What do you mean by living organism?

Ans. Organism which get energy from the food, respire and grow are called living organisms.

Q4. Name two aquatic plants which are completely submerged in water.
Answer:
Lily and lotus

Q5. Name one characteristic which tells us that seeds are living things.
Answer:
They grow into a plant when get favourable conditions.

Q6. Mention few aquatic plants found in a pond.
Answer:
Water hyacinth, water lily, lotus, Hydrilla, etc.

Q7. Name some plants which live in dry areas.
Answer:
Plants like cactus, Acacia, pine, prickly pear live in dry areas.

Q8. What is stimuli?
Answer:
The changes in our surrounding that makes us respond to them are called stimuli.

Q9. Name an animal in which the exchange of gases, during respiration, take place through its skin.
Answer:
The earthworm breathes through the skin.

Q10. Define ecology.
Answer:
The study of relationship between living organism and their surroundings is called ecology.

Answer the following question in 30 to 40 words

Q11. What is a habitat?

Solution:

The place where organisms live is called the habitat. Habitat means a dwelling place (a home). The habitat provides food, water, air, shelter and other needs to organisms.

Q12. How is a cactus adapted to survive in a desert?

Solution:

Adaptations of a cactus are as follows:

• The leaf is replaced by the spine to reduce transpiration
• Stems carry out photosynthesis
• A thick waxy layer surrounds the leaf to retain water
• The roots of a cactus are deeply rooted inside the soil to absorb water.

Q13.  Give an example of a nonliving thing which shows any two characteristics of living things.

Solution:

Example: car

Features

• It can move like living beings
• It needs energy to do work

Q14. List the common characteristics of living things.

Solution:

Common characteristics of living things are as follows:

i) Respiration

ii) Food intake

iii) Respond to stimuli

iv) Excretion

v) Movement

vi) Reproduction

vii) Grow and die

Q15. Explain why speed is important for survival in the grasslands for animals that live there. (Hint: There are few trees or places for animals to hide in grassland habitats.)

Solution:

Speed is important for survival in the grasslands for animals to avoid predation from their predators. For example, a tiger eats deer; to survive, the deer has to run faster than the tiger.

 

Answer the following question in 50 to 60 words:

Q16. Differentiate between xerophytes and hydrophytes.
Answer:

Xerophytes	Hydrophytes
1. Plants are adapted to dry conditions.	1. Plants are adapted to aquatic conditions.
2. Leaves are reduced in size or are modified to spines to reduce transpiration.	2. Leaves are broad for floating or ribbon-shaped to allow water current through it.
3. Roots are long and well developed.	3. Roots are not very well developed. Their main function is just anchoring the plant.
4. Example, Cactus, Acacia	4. Example, Hydrilla, Vallisneria