8th Class Biology Textbook PDF

8th Class Biology Textbook PDF Overview

Question 1. What is Science?
Answer: Science:

1. Science is the concerted human effort to understand the history of the natural world and how the natural world works, with observable physical evidence.
2. Science is an organized study of knowledge that is based on experimentation.
3. Science is a tool for searching for the truths of nature.
4. Science is a way of exploring the world.

Question 2. What are scientific methods? Write the steps involved in a scientist’s work.
Answer: Scientific Methods:

1. Scientists solve a problem or answer a question using organized ways. They are called “Scientific Methods”.
2. The following are the steps involved in scientific work.
   a) Step -1 Ask questions.
   b) Step – 2 Form hypothesis.
   c) Step – 3  Plan experiments.
   d) Step – 4 Conduct experiments.
   e) Step – 5 Draw conclusions.

Question 3. What is the way to find out solutions to problems in a scientific way?
Answer:
To find out solutions for the problems in a scientific way we need to follow a sequential order. So we go through the following.

1. Identifying problem: Let us identify any problems from your surroundings.
   Ex: The bulb did not light in the room.
2. Making hypothesis: List out different solutions which your think for the identifying problem.
   Ex: De filament, fuse failure, switch problem, wire problem.
3. Collecting information: To solve the identifying problem collect material, apparatus, Information, and persons.
   Ex: Collect material like a tester, screwdriver, wooden scale, wires, insulation tape, table, and blade.
4. Data analysis: Arrange the collected data or information to conduct an experiment.
5. Experimentation: To prove to select a hypothesis conduct an experiment.
   Ex: Observe the filament of the bulb.
6. Result analysis: Analyzing the results to find out the solution for the problem based on the results you need to select another hypothesis to prove.
   Ex: The filament of the bulb is good in condition so we need to observe the fuse.
7. Generalization: Based on the experiment and its results explain the solution for the problem.
   Ex: Fuse is damaged so the bulb does not glow, so we need to replace the fuse.

Question 4. During the investigation in science, name some rules to be followed for safety.

Answer:

1. Think ahead: Study the steps of the investigation, so you know what to expect.
2. Be neat: Keep your work area clean.
3. Oops!: If you should spill or break something or get cut, tell your teacher right away.
4. Watch your eyes: Wear safety goggles anytime you are directed to do so.
5. Yuck!: Never eat or drink anything during a scientific activity.
6. Protect yourself from shocks: Be especially careful if an electric appliance is used. Be sure that electric cords are in a safe place where you can’t trip over them. Don’t ever pull a plug out of an outlet by pulling on the cord.
7. Keep it clean: Always clean up when you have finished.

Question 5. If you plan a test to find out how much water different brands of paper towels absorb, write

down the steps of the experiment.

Answer:

1. Pour 1 litre of water into each of the three beakers.
2. Put a towel from each of the three brands into a different beaker for 10 seconds.
3. Pull the towel out of the water, and let it drain back into the beaker for 5 seconds.
4. Measure the amount of water left in each beaker.
5. The towel put in the beaker in which less amount of water is left absorbs more water.

Question 6. Collect information about scientists and their works and prepare a chart and paste it into your classroom.

Answer:

Question 7. What are process skills?

Answer:

Observing, comparing, and classifying are the process skills.

1. Observe – Use the senses to learn about objects and events.
2. Compare – Identify characteristics of things or events to find out how they are alike and different.
3. Classify – Group or organize objects or events in categories based on specific characteristics.

Question 8. Read the following.

Answer: Endemic Species:

You may find that these animals are specifically found in certain regions of the world.
You are also aware of the fact that many plants and animals are widely distributed throughout the world. But some species of plants and animals are found restricted to some areas only. Plants or animal species found restricted to a particular area of a country are called Endemic Species.
Now answer the following questions.
a) Name an Endemic Species of our State.
Answer:
Tiger, Peacock, and Crane.

b) You may notice that Kangaroo is endemic to Australia and Kiwi to New Zealand. Can you tell which among the above pictures represents an endemic species of India?
Answer: Peacock and Tigere are other endemic species of India.
Answer: Indian Lion, Indian Wolf, Great Indian bustard bill.

You can download the 8th Class Biology Textbook PDF by going through the following download link.