8. Cell—Structure and Functions (CBSE) Class 8 Science Exemplar Questions and Solutions

Class 8 Science Exemplar Chapter 8 : Cell—Structure and Functions | MCQ Test Questions, Short Answer Questions, and Long Answer Questions with Explanation

Chapter 8 : Cell—Structure and Functions

1.Choose the correct statement with respect to unicellular organisms:
(a)in unicellular organisms, tissues work in co-ordination to perform different functions.
(b)unicellular organisms do not require food.
(c)unicellular organisms respire and reproduce.
(d)all unicellular organisms move by cilia.
2.Majority of cells cannot be seen directly with our naked eyes because:
(a)organisms are generally unicellular
(b)cells are microscopic
(c)cells are present only inside the body
(d)cells are grouped into tissues
3.Read the different combinations of terms given below:
(a)cell wall, cell membrane, nucleus, plastid
(b)cell wall, nucleus, ribosome, chromosome
(c)cell membrane, mitochondria, ribosome, chromosome
(d)cell membrane, ribosome, mitochondria, chloroplast.
The correct combination of terms with reference to an animal cell is _____.

4.Which one of the following term is not a part of the nucleus?
(a)ribosome     (b)nucleolus (c)chromosome  (d)gene
5.A suitable term for the various components of cells is
(a)tissue        
(b)cell organelles (c) chromosomes  (d)genes
6.The jelly-like fluid substance present in cells is called
(a)protoplasm  
(b)chromosome (c)chloroplast  (d)cytoplasm

7.Read the following pairs of examples of organisms:
(a)moss and sponge     
(b)yeast and Amoeba (c)bacteria and blue-green alga  (d)penicillium and Spirogyra
The pair that belongs to the group prokaryotes is_____
8.Read the following terms and select the pair that is related to inheritance of characters.
(a)cell wall and cell membrane
(b)chromosome and mitochondria
(c)chloroplast and cell membrane
(d)chromosome and genes
9.Choose the correct statement:
(a)Genes are located in the chromosomes.
(b)Cell is located in the nucleus.
(c)Chromosomes are located in the nucleolus.
(d)Cell membrane surrounds the nucleus.

10.Green colour of leaves is due to presence of the pigment_____
(a)chlorophyll   (b)ribosomes (c)mitochondira (d)chloroplast
11.The unit of measurement used for expressing dimension (size) of cells is:
(a)centimeter       (b)millimeter (c)micrometer   (d)metre
12.The most important function of cell membrane is that it:
(a)controls the entry and exit of materials from cells.
(b)controls only the entry of materials into cells.
(c)controls only the exit of materials from cells.
(d)allows entry and exit of materials without any control.
13.Paheli accidentally placed her hand over a flame and immediately pulled it back. She felt the sensation of heat and reacted due to the action of
(a)blood cells  
(b)skin surface (c)nerve cells  (d)nucleus of cells
14.Of the following parts of a cell listed below, name the part that is common to plant cell, animal cell and a bacterial cell.
(a)chloroplast      
(b)cell wall  (c)cell membrane     (d)nucleus

15.The thread-like structures present in the nucleus are
(a)nucleolus         
(b)chromosomes  (c)genes     (d)ribosomes
16.Identify the statement which is true for cells.
(a)Cells can be easily seen with naked eyes.
(b)Insect’s egg is not a cell.
(c)A single cell can perform all the functions in a unicellular organism.
(d)The size and shape of cells is uniform in multicellular organisms
17.Which of the following is not a cell?
(a)Red Blood Corpuscle (RBC)
(b)bacterium
(c)spermatozoa
(d)virus
18.Which of the following feature will help you in distinguishing a plant cell from an animal cell?
(a)cell wall    (b)cell membrane (c)mitochondria (d)nucleus

19.Under a microscope Paheli observes a cell that has a cell wall but no distinct nucleus. The cell that she observes is
(a)a plant cell           
(b)an animal cell   (c)a nerve cell        (d)a bacterial cell
20.Cheek cells do not have _______
(a)cell membrane        (b)nucleus   (c)golgi apparatus  (d)plastids
21.Identify the correct statement.
(a)Tissue is a group of dissimilar cells.
(b)An organ consists of similar cells.
(c)Vacuoles are not found in plant cells.
(d)Prokaryotes do not have nucleus.
22.Which of the following statements are true for eukaryotic cells?
(i)They do not have a nuclear membrane.
(ii)They have a well organised nucleus.
(iii)They have a nuclear membrane.
(iv)Blue green algae are eukaryotic cells.

(a)ii and iv              (b)ii and iii
(c)i and ii                (d) i and iv
23.Identify the correct statement about cells.
(a)All the cells have nucleus.
(b)Cells of an organ have similar structure.
(c)Cells of a tissue have similar structure.
(d)Shape of all types of cells is round.

   VERY SHORT ANSWER QUESTIONS
25. In leaves, name the cell organelle and pigment that is responsible for green colour.
26. The instrument used to observe cells is ________
27. We do not sense any pain when we clip our nails or cut our hair. Why?
28. In a cell, where are the genes located?
29. Amoeba and Paramecium belong to which category of organisms?

30. What are the functions of cell wall in plant cells?
S HORT ANSWER QUESTIONS
31. Is the following statement correct? If it is wrong, correct the statement
Statement : “Unicellular organisms do not respire, only multicellular organisms respire”
32. Match the terms given in column I with their functions given in column II and fill the blanks given below the table:

Column I                Column II
A. Chloroplast           (i) carries hereditary characters
B. Cell membrane      (ii) controls the activities of cells
C. Nucleus                  (iii) site of photosynthesis
D. Chromosome          (iv) controls the movement of materials into and out of cells.
A-_____; B-______; C-______; D-______ .

5. Classify the following terms into cells, tissues and organs and write in the tabular column given below.
RBC, WBC, Nerve cell, blood, muscle, blood vessels, brain, heart, hand

Cell                 Tissue                Organ
..............    ..............         ..............
..............     ..............          ..............
..............     ..............            ..............

37.Fill in the blanks with the terms given in the box below:
Nucleus, chromosomes, cell wall, cell membrane, protoplasm, cytoplasm, ribosome, cell organelles
The outermost layer of plant cells is the…..(a)……… beneath which is the……(b)……. . The term ……(c)…….. refers to the jelly-like substance containing all the ……… (d)……… . The……… (e)……….. contains thread-like structures called ……….(f)……….. .

LONG ANSWER QUESTIONS
38. Cells consist of many organelles, yet we do not call any of these organelles as structural and functional unit of living organisms. Explain.
39. Why do plant cells have an additional layer surrounding the cell membrane? What is this layer known as?
40. The size of the cells of an organism has no relation with the size of its body. Do you agree? Give reason for your answer.

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Posted 3 months ago