Send me the MCQ based on class 8 science chapter 8
cell structure and function
Answers
1. Which organelle is called the “powerhouse of the cell”?
A. Nucleus
B. Endoplasmic reticulum
C. Mitochondrion
D. Golgi apparatus
Answer: (C) Mitochondrion
Solution: The mitochondrion is called the “powerhouse of the cell” because it is responsible for producing energy-rich ATP molecules. Cells use ATP for all their energy needs.
2. Which of the following instruments can be used to observe cells?
A. Barometer
B. Microscope
C. Periscope
D. Telescope
Answer: (B) Microscope
Solution: A microscope is an optical instrument used to observe objects that are invisible to the naked eye. It is used to view and study cell structure. The science of viewing small objects using a microscope is called microscopy.
3. Which of the following scientists discovered cells in cork slices?
A. Louis Pasteur
B. Antonie van Leeuwenhoek
C. Carl Linnaeus
D. Robert Hooke
Answer: (D) Robert Hooke
Solution: Robert Hooke in 1665 observed thin slices of cork under a simple magnifying device. He observed box-like structures and named them ‘cells’. This is because these structures reminded him of the cells in a monastery.
4. Which among the following organelles synthesizes lipids?
A. Smooth Endoplasmic Reticulum
B. Rough Endoplasmic Reticulum
C. Golgi apparatus
D. Lysosome
Answer: (A) Smooth Endoplasmic Reticulum
Solution: Lipids are synthesised by the Smooth Endoplasmic Reticulum (SER), while the Rough Endoplasmic Reticulum (RER) synthesises proteins with the help of ribosomes attached to them.
5. Which of the following statements is incorrect about Endoplasmic Reticulum?
A. It is involved in lipid synthesis.
B. It is involved in ribosome synthesis.
C. It is the post office of the cell.
D. Involved in detoxifying chemicals.
Answer: (C) It is the post office of the cell
Solution:
∙ Golgi apparatus is called the post office of the cell since it is involved in the packaging, processing and transportation of substances.
∙ SER (Smooth endoplasmic reticulum) is involved in detoxification and lipid synthesis, while RER is involved in protein synthesis. Ribosomes are not synthesised by the ER.
6. Which among the following is not the function of lysosomes?
A. Breaking down of food particles.
B. Protection against the pathogens.
C. Perform photosynthesis.
D. Digest worn-out cells.
Answer: (C) Perform photosynthesis
Solution: Lysosomes break down and digest food particles in a cell. They also help the cell to protect itself from pathogens, by forming a complex along with the pathogen, called phagosome. They also aid in recycling proteins and digest worn-out cells. Hence, they are known as the ‘suicidal bags’. But they do not aid in photosynthesis.
7. Assertion (A): Chromosomes are responsible for the transfer of characteristics from parents to offspring.
Reason (R): Chromosomes are present in the nucleus.
A. Both A and R are true and R is the correct explanation of A
B. A is true but R is false
C. A is false but R is true
D. Both A and R are true but R is not the correct explanation of A
Answer: (D) Both A and R are true but R is not the correct explanation of A
Solution: In the nucleus, thread-like structures called chromosomes are present. These carry all the information needed by the cell to function and to reproduce. They are responsible for inheritance i.e., transfer of characteristics from parents to the offspring. Hence, both the statements are correct. Chromosomes being present in the nucleus has nothing to do with their function.
8. Among the following which cell can be seen with an unaided eye?
A. Hen’s egg
B. Red blood cell
C. Sperm cell
D. Nerve cell
Answer: (A) Hen’s egg
Solution: Most of the cells are microscopic in size and are not visible to the unaided eye. They need to be enlarged or magnified by a microscope. Some cells are big enough to be seen with the unaided eye. Example of that is a hen’s egg which is considered as a single cell. It can be seen by the naked eye.
9. The fluid present between the cell membrane and the nucleus is called
A. Cytoplasm
B. Nucleoplasm
C. Protoplasm
D. Serum
Answer: (A) Cytoplasm
Solution: The jelly-like fluid present between the cell membrane and the nuclear membrane is called the cytoplasm. It houses all the cellular organelles and is the site for most of the metabolic activities taking place in the cell.
10. Choose the correct statement(s):
(i) Ribosomes are located on the chromosomes.
(ii) Cell is located in the nucleus.
(iii) Chloroplasts are located in the nucleolus.
(iv) Cell membrane surrounds the cell.
A. (i), (ii) and (iii)
B. (i) and (ii)
C. (iii) and (iv)
D. Only (iv)
Answer: (D) Only (iv)
Solution:
Ribosomes are protein synthesising units which are present attached to the RER or are freely floating in the cytoplasm.
Nucleus is present in the cell.
Chloroplasts are present in the cytoplasm of plant cells.
Nuclear membrane surrounds the nucleus and cell membrane surrounds the cell
Answer:
1. Which organelle is called the “suicide bag of the cell”?
A. lysosome
B. Endoplasmic reticulum
C. Mitochondrion
D. Golgi apparatus
2. Which of the following instruments can be used to observe cells?
A. Barometer
B. Microscope
C. Periscope
D. Telescope
3. Which of the following scientists discovered "nucleus" ?
A. Louis Pasteur
B. Antonie van Leeuwenhoek
C. Carl Linnaeus
D. Robert Hooke
4. Which among the following organelle is semi autonomous?
A. Smooth Endoplasmic Reticulum
B. Rough Endoplasmic Reticulum
C. Golgi apparatus
D. MItochondria
5. Which of the following statements is incorrect about Endoplasmic Reticulum?
A. It is involved in lipid synthesis.
B. It is involved in ribosome synthesis.
C. It is the post office of the cell.
D. Involved in detoxifying chemicals.
6. Which among the following is the function of "chloroplast" ?
A. Breaking down of food particles.
B. Protection against the pathogens.
C. Perform photosynthesis.
D. Digest worn-out cells.
7. Assertion (A): Chromosomes are responsible for the transfer of characteristics from parents to offspring.
Reason (R): Chromosomes are present in the nucleus.
A. Both A and R are true and R is the correct explanation of A
B. A is true but R is false
C. A is false but R is true
D. Both A and R are true but R is not the correct explanation of A
8. In which of the following cell or tissue can be seen in 3D?
A. naked eye
B. simple microscope
C. compound microscope
D. electron microscope
9. The fluid present in the nucleus is called
A. Cytoplasm
B. Nucleoplasm
C. Protoplasm
D. Serum
10. Choose the correct statement(s):
(i) Ribosomes are located on the chromosomes.
(ii) Cell is located in the nucleus.
(iii) Chloroplasts are located in the nucleolus.
(iv) Cell membrane surrounds the cell.
A. (i), (ii) and (iii)
B. (i) and (ii)
C. (iii) and (iv)
D. Only (iv)
Explanation:
1. A
2. B
A microscope is an optical instrument used to observe objects that are invisible to the naked eye. It is used to view and study cell structure.
3. D
Robert Hooke discovered "nucleus" in 1831
4. D
Mitochondria is a semi autonomous cell organelles since it possesses its own DNA and ribosomes unlike other cells.
5. C
Golgi apparatus is called the post office of the cell since it is involved in the packaging, processing and transportation of substances.
6. C
Chloroplasts are plant cell organelles that convert light energy from Sun into relatively stable chemical energy via the photosynthetic process.
7. D
In the nucleus, thread-like structures called chromosomes are present. These carry all the information needed by the cell to function and to reproduce. They are responsible for inheritance i.e., transfer of characteristics from parents to the offspring. Hence, both the statements are correct. Chromosomes being present in the nucleus has nothing to do with their function.
8. D
9. B
10. D
Ribosomes are protein synthesizing units which are present attached to the RER or are freely floating in the cytoplasm.
Nucleus is present in the cell.
Chloroplasts are present in the cytoplasm of plant cells.
Nuclear membrane surrounds the nucleus and cell membrane surrounds the cell
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