NCERT Solutions for Class 8 Science Chapter 8 Cell: Structure and Functions help students to clear all their doubts. These solutions provide you with the answers to all the questions given in the NCERT textbook. CBSE Class 8 Science Chapter 8 Solutions is prepared by expert teachers as per the latest CBSE syllabus and guidelines.
Solving NCERT Solutions will help you to understand the concepts related to Cell: Structure and Functions. NCERT Solutions for Class 8 Science Chapter 8 contains an in-depth explanation of each question of NCERT Science textbook. These solutions cover important concepts in different patterns like MCQs and short answer questions, worksheets and more and help you top score good marks in the exam.
NCERT Solutions for Class 8 Science Chapter 8 Cell: Structure and Functions PDF
Question 1: Indicate whether the following statements are True (T) or False (F)
(a) Unicellular organisms have one-celled body. (T/F
(b) Muscle cells are branched. (T/F)
(c) The basic living unit of an organism is an organ. (T/F)
(d) Amoeba has irregular shape. (T/F)
Question 2: Make a sketch of the human nerve cell. What function do nerve cells perform?
Answer: The nerve cell receives and transfers messages, thereby helping to control and coordinate the working of different parts of the body.
Question 3: Write short notes on the following:
(b) Nucleus of a cell
Answer: (a) Cytoplasm: The jelly-like substance between the nucleus and the cell membrane is called cytoplasm. Various cell organelles like ribosomes, mitochondria etc. are suspended inside the cytoplasm. It helps exchange and storage of substances among cell organelles. Most of the metabolic activities occur inside the cytoplasm.
(b) Nucleus of a cell: The central dense round body in the centre is called the nucleus. It is an important component of the living cell. It is generally spherical and located in the centre of the cell. It can be stained and seen easily with the help of a microscope. Nucleus is separated from the cytoplasm by a membrane called the nuclear membrane. This membrane is also porous and allows the movement of materials between the cytoplasm and the inside of the nucleus. A smaller spherical body in the nucleus, is called the nucleolus. Nucleus also contains thread-like structures called chromosomes. These carry genes and help in inheritance or transfer of characters from the parents to the offspring.
Question 4: Which part of the cell contains organelles?
Answer: Cytoplasm, gelatinous fluid inside a cell contains various organelles like mitochondria, Golgi bodies, ribosomes etc.
Question 5: Make sketches of animal and plant cells. State three differences between them.
|Plant cell||Animal cell|
|They are large in size||They are smaller than plant cells|
|The cell wall is present||The cell wall is absent|
|Vacuoles are large||Vacuoles are small|
|Plastids could be seen||Except for Euglena, Plastids could not be seen in animal cells.|
Question 6: State the difference between eukaryotes and prokaryotes.
Answer: Prokaryotes: The cells having nuclear material without a nuclear membrane are termed as prokaryotic cells. The organisms with these kinds of cells are called prokaryotes.
Examples: Bacteria and blue-green algae.
Eukaryotes: The cells having a well-organized nucleus with a nuclear membrane are termed as eukaryotic cells. The organisms with these kinds of cells are called eukaryotes.
Examples: Onion cells and cheek cells.
|Most of them are unicellular||Most of them are multicellular|
|There is no nuclear membrane. So,the nucleus is poorly defined.||There is a nuclear membrane. So, the nucleus is well defined.|
|Not all cell organelles are present||All the cell organelles are present.|
|Nucleolus is absent||Nucleolus is present|
|Eg: Blue-green algae, Bacteria||Eg: Plant, Animal cells and Fung|
Question 7: Where are chromosomes found in a cell? State their function.
Answer: Chromosomes are found in the nucleus of the cell. These carry genes and help in inheritance or transfer of characters from the parents to the offspring.
Question 8: ‘Cells are the basic structural units of living organisms’. Explain.
Answer: Both, bricks in a building and cells in the living organisms, are basic structural units. All basic functions for the organism survival take place inside cells. As bricks assemble to make a building, cells assemble to make the body of every organism. A group of cells form a tissue which performs a specific function. A group of tissue forms an organ and in the same way a group of organs form an organism. That is why cells are considered as the basic structural units of living organisms.
Question 10: Complete the crossword with the help of clues given below:
1. This is necessary for photosynthesis.
3. Term for component present in the 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.