Chapter 10 Living Creatures: Exploring their Characteristics Class 6 Science Curiosity NCERT Solutions
Chapter 10 Living Creatures: Exploring their Characteristics NCERT Solutions Class 6 Science
Question 1. How would you now categorise a seed, as living or non-living?
Answer
Seed is a living thing as it can germinate and grow into a plant under favourable conditions.
Question 2. How can the life cycle of a mosquito be disrupted?
Answer
Larvicides (a substance used to kill larvae) target larvae in the breeding habitat before they can mature into adult mosquitoes and disperse. Larvicide treatment of breeding habitats helps reduce the adult mosquito population in nearby areas.
Liquid larvicide products are applied directly to water using backpack sprayers and truck or aircraft-mounted sprayers. Tablet, pellet, granular, and briquet formulations of larvicides are also applied by mosquito controllers to breeding areas.
Activity 10.2
When a seed turns into a sprout, it is said to have germinated. Predict whether the seeds in each pot will germinate. Record your predictions for each pot kept under different conditions in Table.
Answer
|
Pot with bean seeds |
Availability of |
Seed germination |
Possible reason for the observation |
|||
|
|
Air |
Sunlight |
Water |
Prediction |
Observation |
|
|
A: In direct sunlight and without water |
Yes |
Yes |
No |
No |
No seed germination |
Water is necessary for the germination of seed |
|
B: In direct sunlight and excess water |
Yes |
Yes |
Yes (excess) |
Yes |
No, proper seed germination |
In presence of excess water, seed not disappear. So, seed cannot germinate properly. |
|
C: In complete dark and moist soil |
Yes |
No |
Yes (limited) |
Yes |
Yes, seed can be germinate |
Light is not necessary for seed germination. Majority of seeds grow efficiently in dark |
|
D: In direct sunlight and moist soil |
Yes |
Yes |
Yes (limited) |
Yes |
Yes, seed can be germinate |
Seed will germinate as moist soil provide effective condition and also the presence of sunlight. |
Let us enhance our learning
1. List the similarities and differences in life cycles of plants and animals.
Answer
Similarities in Life Cycles of Plants and Animals
- Both animals and plants have distinct life stages starts with initial stage and followed by several stages of development and lastly death.
- Both have reproductive stages where they produce offsprings.
- Both animals and plants have male and female organs required for reproduction.
Differences in Life Cycles of Plants and Animals
|
Life Cycle of Plants |
Life Cycle of Animals |
|
A plant’s life cycle starts with seed germination. |
An animal’s life cycle begins with a new born or egg. |
|
Plants grow throughout their life. |
Animals stop growing after certain stage of time. |
|
Seeds or reproductive parts are produced throughout their life cycle. |
Animals have definite time for reproduction. |
|
Plants do not move from one place to another. |
Animals move from one place to another. |
|
Plants use flowers, cones, or spores. |
Animals have specialized organs for reproduction |
|
Plants use stomata and lenticels for the respiration. |
Animals have specialised organs like lungs or gills for respiration. |
2. The table on the next page shows some data. Study the data and try to find out examples appropriate for the conditions given in the second and third columns. If you think that an example for any of the conditions given below is not possible, explain why.
Answer
|
Does it grow? |
Does it respire? |
Example |
Remarks |
|
No |
No |
Book |
Non-living thing, No growth and respiration |
|
No |
Yes |
Virus |
Virus are non-living thing when left alone but respire when it find a host. |
|
Yes |
No |
Sand dunes |
Sand tunes get big and small according to wind but do not respire as it is non-living things. |
|
Yes |
Yes |
Humans, Plans |
Living things which can grow and respire as well. |
3. You have learnt that different conditions are required for seed germination. How can we use this knowledge for proper storage of grains and pulses?
Answer
We learnt that water, air and suitable temperature are required for seed germination. So, we will store the grains and pulses in cool and dry place such as:
- Cold Storage
- Airtight Containers
4. You have learnt that a tail is present in a tadpole but it disappears as it grows into a frog. What is the advantage of having a tail in the tadpole stage?
Answer
The tail in the tadpole stage helps it in:
- The tail helps the tadpole in swimming and changing direction in water.
- The tail also helps it in finding food and keeping itself safe from predators
- Is also helps the tadpole in maintaining balance and stability while moving in water.
5. Charan says that a wooden log is non-living as it cannot move. Charu counters it by saying that it is living because it is made of wood obtained from trees. Give your arguments in favour or against the two statements given by Charan and Charu.
Answer
- Against Charan: The wooden log was once part of a living tree, which was alive and exhibited characteristics of living beings.
- Against Charu: Once the wood is separated from the tree, it cannot move, respire, grow or perform any other life processes, making it non-living.
6. What are the similarities and distinguishing features in the life cycles of a mosquito and a frog?
Answer
Similarities between life cycle of Mosquito and Frog:
- Life cycle of both, frog and mosquito, has four stages.
- Both begin life as eggs.
- Both have a larval stage (tadpole in frogs, larvae in mosquitoes) that is aquatic.
Differences between life cycle of Mosquito and Frog:
|
Life Cycle of Mosquito |
Life Cycle of Frog |
|
1. Life cycle of mosquito has four stages—egg, larva, pupa and adult. |
1. The life cycle of frog has four stages— egg, tadpole, froglet and adult frog. |
|
2. The adult mosquito cannot live in water. |
2. The adult frog can live both on land and in water. |
|
3. The adult mosquito may survive for 10 to 15 days. |
3. The adult frog may survive for 14 weeks. |
|
4. Larvae and pupae breathe through siphons. |
4. Tadpoles have gills, adults have lungs and can respire through their skin. |
7. A plant is provided with all the conditions suitable for its growth (Fig. 10.9). Draw what you expect to see in the shoot and the root of the plant after one week. Write down the reasons.
Answer
Expected observations:
- Shoot: Growth upwards, exhibit movement towards sunlight.
- Root: Growth downwards, exhibit movement towards the soil
Reasons:
- Shoots grow towards light (phototropism) for photosynthesis.
- Roots grow downwards (gravitropism) for stability and nutrient absorption.
8. Tara and Vijay set up the experiment shown in the picture (Fig. 10.10). What do you think they want to find out? How will they know if they are correct?
Answer
Tara and Vijay want to find out in which direction the root and shoot of a plant would grow and move if the plant is placed inverted or along the ground.
Observation: The shoot always grows upwards (towards the light) and the root always grows downwards (into the soil), regardless of how the seed is placed, this shows that plants have natural mechanisms (like phototropism and gravitropism) that guide their growth direction.
9. Design an experiment to check if temperature has an effect on seed germination.
Answer
Aim: To check if temperature has an effect on seed germination.
Materials: Identical pots, soil, seeds, thermometers, and different temperature controlled environments (e.g., refrigerator, room temperature, heated environment).
Procedure:
- Each pot is filled with the same type of soil.
- Seed is planted in each pot.
- Now, each pot is kept in a different environment with controlled temperatures (e.g., cold temperature, room temperature and warm temperature).
For example: one pot outside in balcony to get sunlight, another pot in shade in the room and the third one in basement or at coldest part of the house. - Each pot is given water in equal quantity.
- Number of seeds germinated in each environment is recorded daily for two weeks.
Observation: Measure and compare the rate of germination and growth in different temperatures.
Conclusion: Determine the optimal temperature for seed germination based on observations.