Skip to main content

CBSE Class 8 Biology: Cell Structure and Functions Questions & Answers

  1. Indicate whether the following statements are True (T) or False (F).
    (a) Unicellular organisms have one-celled body. (T / F ) - True.
    (b) Muscle cells are branched. - (T / F) - False
    (c) The basic living unit of an organism is an organ. (T / F) - False
    (d) Amoeba has irregular shape. - (T / F) - True.

  2. Make a sketch of the human nerve cell. What function do nerve cells perform?
    Nerve cells receive and transfer messages, thereby helps to control and coordinate the working of different parts of the body.

  3. Write short notes on the following:
    (a) Cytoplasm
    (b) Nucleus of a cell
    (a) Cytoplasm: The jelly-like substance present between the cell membrane and the nucleus. It contains various other components or organelles like mitochondria, golgi bodies, ribosomes etc.

    (b) Nucleus of a cell:
    • It is an important component of the living cell.
    • It acts as control centre of all the activities in a cell.
    • It is generally spherical and is located in the centre of the cell.
    • It is separated from the cytoplasm by a membrane called nuclear membrane.
    • The nuclear membrane is porous and allows the movements of materials between the cytoplasm and inside of the nucleus.
    • It contains a smaller spherical body called the nucleolus and thread-like structures called chromosomes that that appear only during cell division.
    • These chromosomes carry genes which help in the transfer of characters from parents to offsprings.

  4. Which part of the cell contains organelles?
    Cytoplasm contains the nucleus and various other components or organelles like mitochondria, golgi bodies, ribosomes etc.

  5. Make sketches of animal and plant cells. State three differences between them.

  6. State the difference between eukaryotes and prokaryotes.

    All the organisms other than bacteria and blue green algae that are made of cells with a well-organized nucleus having a nuclear membrane are called eukaryotes. Whereas bacterial cells that are not well-organized and the nuclear material is not bound by a nuclear membrane are called prokaryotes.

  7. Where are chromosomes found in a cell? State their function.
    Ans. Chromosomes are found in the nucleus of a cell. They carry genes which help in the transfer of characters from parents to their offsprings. Chromosomes are seen only during cell division.

  8. 'Cells are the basic structural units of living organisms'. Explain.
    Living organims differ from one another in shape and size. However all living organisms are made up of cells which are complex living structures. Hence, cells are called the basic structural units of living organisms.

  9. Explain why chloroplasts are found only in plant cells.
    Chloroplasts are the green colored plastids present in the leaves. They contain chlorophyll which is essential for photosynthesis as they are capable of trapping sunlight.

  10. Complete the crossword with the help of clues given below:
    1. This is necessary for photosynthesis.
    3. Term for component present in cytoplasm.
    6. The living substance in the cell.
    8. Units of inheritance present on the chromosomes.

    1. Green plastids
    2. Formed by collection of tissues.
    4. It separates the contents of the cell from the surrounding medium.
    5. Empty structure in the cytoplasm.
    7. A group of cells.


Popular posts from this blog

Seemantham - The South Indian Traditional Baby Shower ceremony

Seemantham is a traditional south Indian way of celebrating baby shower. The same is celebrated in north India as 'godbharai' ('god' means lap in Hindi - 'd' in 'god' is pronounced as 'the' and bharai means 'to fill'). The celebration differs from region to region. Seemantham is also known by the names 'poolu mudupu' (i.e adoring flowers in the hair) and 'gajulu todagadam' (i.e wearing glass bangles) in Telugu. It is celebrated in the 5th or 7th or 9th month of pregnancy. Seemantham is one of the 16 Hindu samskaras known as 'simantonnayana' in Sanskrit. It is a samskara of the embryo / foetus that develops in the pregnant woman's womb. Usually, seemantham is celebrated for the 1st pregnancy only and not for the subsequent conceives. There are certain superstitious believes on celebrating the function. In the olden days, people believed that pregnant women are easily prone to 'dishti' or evil e

How To Perform Aksharabhyasam At Home And Basar temple

Aksharabhyasam Meaning The word 'Akshara' means letters (alphabets) in Sanskrit and 'abhyasam' means practice. Aksharabhyasam is a traditional religious function of Hindus. It is also known as 'Vidyaarambham' which literally means starting of education. In this function a child is given initiation for writing / education. With this function the child is ready to receive formal education in a school. The function is performed in different ways in different regions of India. When to perform aksharabhyasam In the olden days, aksharabhyasam was performed when the child was 5 years old. But presently because of early education at Kindergarten level, parents perform this ceremony when the child is in his 3rd year i.e. after the child completes 2 years. Normally there is a belief that aksharabhyasam should not be performed after the child completes 3 years and is in its 4th year. Where to perform aksharabhyasam The function can be performed either in a temp

School Speeches - Farewell Speech By School Principal to Outgoing Students

Author Reserves All Rights. Listen to the speech in my YouTube Channel: This sample speech would be helpful for the school principal to deliver on the occasion of school farewell day party. Respected teachers and my dear students, Good Morning / Good Afternoon to each one present here and a very warm welcome to you to the school farewell party. It's a nostalgic feeling as I remember my student life in school and my school farewell party. I am sure we all have mixed feelings on this day which is a blend of joy and sadness. On one hand you feel enthusiastic as you will be stepping into a completely new different world where you will find relatively more freedom than in a school life. While on the other hand you will feel sad as you have to depart from your school / classmates. My dear friends the time has come to bid you all farewell with a heavy heart from this esteemed institution which protected you, cared for you, supported you and guided you all these years.