CBSE Sample Paper 2021 Class 8 Science Half Yearly

Half Yearly Examination (2020-21)


Time:2:30 hours

Maximum Marks:80

Subject: Science

All questions are compulsory.

1- Choose the correct options:- (6)

i) Coal mainly contains :-

a- Carbon

b- Sodium

c- Hydrogen

ii) Which of these is not a source of energy?

a- Plastic

b-  sun

c- Coal

iii) Which of these does not help in starting fire?

a- Heat

b- fuel

c- Water

iv) Which of the following is not a natural?

a- Grassland

b- aquarium

c-  Chloroplasts

v) Male gonads are called –

a- Testes

b- ovaries

c- penis

2- Match the following :-(6)

A                                              B

i) Cell wall                      Hydra

ii) Nucleus                      female gametes

iii) Ribosome                  controls all the activities of the cell.

iv) Egg                             Amoeba

v) Budding                      Protein synthesis

vi) Binary fission             Protection and shape

3- Fill in the blanks :- (8)

i- The liquid fossil fuel is ____________.

ii- ____________ should never be used in case of an electrical fire.

iii- The animals nearing extinction are called ____________.

iv- Internal fertilization takes place in____________.

v- ____________ are the female gonads of human beings.

vi- ____________ involves the splitting of an organism into two.

vii- ____________ release sperm.

viii- In humans fertilization occur in____________.

4- Write T for the true statement and F for the false statements: -(8)

i- Large – sized vacuoles are present animal’s cells.

ii- The cell membrane is selectively permeable.

iii- Flora means plants and fauna means animals.

iv- Ecosystem is the clearing of forests for agriculture.

v- Centrioles help in cell division in animal cells.

vi- Chromo plasts are found in the green parts of the plants.

vii- Amoeba is a single – Celled animals.

viii- Reforestation could lead to and increases in carbon- dioxide.

5- Give reasons for the following.(8)

i- LPG is a better fuel than wood.

ii- Water should not be used in case of a fire in a petrol tank or an electric fire.

iii- A washer man uses charcoal for ironing clothes.

iv- CNG is a better fuel for automobiles.

6- Answer the following questions in one word :-(8)

i- Name a cooking gas.

ii- What is called a black gold?

iii- The gradual conversion of fertile soil into wasteland.

iv- What is called if trees are cutting on a large scale?

v- Name a type of coal which has the highest carbon content.

vi- The process of extraction of resources from earth.

vii- Name the compounds made from petroleum.

viii- Name a moth repellent made from coal tar.

7- Short answers type questions. (Do any eight) (16)

i- What is the impact of using excess of fossil fuels?

ii- What are the characteristics of an ideal fuel?

iii- Why are biodiversity parks being made in different ports of India?

iv- Why the nuclease is called the control centre of the cell.

v- List the male and female reproductive organs of human body?

vi- What are the functions of vacuoles?

vii- Why are biodiversity parks being made in different park s of India?

viii- Why substances do produces flames of different colors?

ix- Why is conservation of fossil fuels essential?

x- What are gonads and what do they produce?

8- Long answers type questions (Do any four) (16)

i- Which virus causes AIDS? What are the ways in which it can be transmitted?

ii- Explain menstrual cycle and the changes that occur in an adolescent girl during the menstrual cycle?

iii- Life begins from a single cell called zygote Explain the statement.

iv- How does fertilization take place in frogs?

v- What are the cell theory states?

vi- How can citizens help in the conservation of plants and animals?

9- Draw any one lablled diagram of the following :- (4)

i- Life cycle of a frog

ii- A plant cell

iii- A candle flame

By cbsepython

A complete solution for the students of class 9 to 12 having subject Information Technology (402), Computer Science (083). Explore our website for all the useful content as Topic wise notes, Solved QNA, MCQs, Projects and Quiz related to the latest syllabus.

Leave a Reply

Your email address will not be published. Required fields are marked *