Please refer to Cell The Unit of Life Class 11 Biology Important Questions with answers below. These solved questions for Chapter 8 Cell The Unit of Life in NCERT Book for Class 11 Biology have been prepared based on the latest syllabus and examination guidelines issued by CBSE, NCERT, and KVS. Students should learn these solved problems properly as these will help them to get better marks in your class tests and examinations. You will also be able to understand how to write answers properly. Revise these questions and answers regularly. We have provided Notes for Class 11 Biology for all chapters in your textbooks.

Important Questions Class 11 Biology Chapter 8 Cell The Unit of Life

Objective Questions

Question. An organalle devoid of membrane covering is
(a) vacuole
(b) ribosome
(c) peroxisome
(d) lysosome

Question. Membranous extensions in blue green algae are known as
(a) phytochrome
(b) chromatophore
(c) mesosome
(d) pneumatophore

Question. Polysome is a chain of
(a) oxysomes
(b) sphaerosomes
(c) ribosomes
(d) dictyosomes

Question. Active transport across biomembrane involves
(a) production of ATP
(b) requirement of energy
(c) production of toxin
(d) release of energy

Question. The lipid component of the membrane mainly consists of __________.
(a) polysaccharides
(b) phosphoglyceride
(c) monosaccharaides
(d) both (a) and (c)

Question. In which of the following the cells are held together by a Ca-pectate layer?
(a) Primary cell wall
(b) Secondary cell wall
(c) Middle lamella
(d) Tertiary cell wall

Question. Which of the following will determines the shape of the cells and provides a strong structural support to prevent the bacterium from bursting or collapsing?
(a) Plasmids
(b) Cell wall
(c) Mesosome
(d) Cell membrane

Statement Type Questions

Question. Which of the following statement of a bacterial cell is/ are correct?
(i) Mesosome is formed by the extensions of plasma membrane into the cell.
(ii) The pili are elongated tubular structures made up of a protein.
(iii) Flagellum is composed of filament, hook and basal body.
(iv) Ribosomes are about 30 nm by 50 nm in size.
(a) (i), (ii) and (iii)
(b) All of the above
(c) (ii) and (iv)
(d) None of the above

Question. According to widely accepted “fluid mosaic model” cell membranes are semi-fluid, where lipids and integral proteins can diffuse randomly. In recent years, this model has been modified in several respects. In this regard, which of the following statements is incorrect?
(a) Proteins in cell membranes can travel within the lipid bilayer.
(b) Proteins can also undergo flip-flop movements in the lipid bilayer.
(c) Proteins can remain confined within certain domains of the membrane.
(d) Many proteins remain completely embedded within the lipid bilayer.

Question. Which of the following statement is false?
(a) The ribosomes of a polysome translate the mRNA into protein.
(b) Mitochondria divide by fragmentation.
(c) All cell arise from pre-existing cells.
(d) The lipid component of the membrane mainly consists of phosphoglycerides.

Matching Type Questions

Question. Match column-I with column-II and choose the correct option.

Column-I (Chromosome)	Column-II (Position of Centromere)
A. Metacentric	I. At the tip
B. Submetacentric	II. Almost near the tip
C. Acrocentric	III. At the middle
D. Telocentric	IV. Slightly away from the middle

(a) A – III; B – IV; C – II; D – I
(b) A – IV; B – III; C – II; D – I
(c) A – I; B – II; C – III; D – IV
(d) A – IV; B – III; C – I ; D – II

Question. Match column-I (scientists) with column-II (discovery) and select the correct option.

Column-I	Column-II
A. Leeuwenhoek	I. First saw and described a living cell
B. Robert Brown	II. Presence of cell wall is unique to plant cells
C. Schleiden	III. Discovered the nucleus
D. Schwann	IV. All plants are composed of different kind of cells

(a) A – I; B – III; C – IV; D – II
(b) A – I; B – III; C – II; D – IV
(c) A – III; B – I; C – IV; D – II
(d) A – I; B – IV; C – II; D – III

Question. Match column-I (cell organelle) with column-II membrane and select the correct option from the codes given below.

Column-I	Column-II
A. Mitochondria	I. Without membrane
B. Lysosomes	II. Single membrane
C. Ribosomes	III. Double membrane

(a) A – I; B – II; C – III
(b) A – III; B – I; C – II
(c) A – III; B – II; C – I
(d) A – II; B – III; C – I

Question. Match column-I with column-II and select the correct option.

Column – I	Column – II
A. RER	I. Intracellular and extracellular digestion
B. Cell wall	II. Provide structural support to the cell
C. Flagella	III. Protein synthesis and secretion
D. Lysosomes	IV. Responsible for cell movement

(a) A – III; B – II; C – IV; D – I
(b) A – II; B – III; C – IV; D – I
(c) A – I; B – III; C – II; D – IV
(d) A – IV; B – II; C – III; D – I

Critical Thinking Type Questions

Question. Golgi apparatus is absent in
(a) higher plants
(b) yeast
(c) bacteria and blue-green algae
(d) None of the above

Question. Which of the following lacks cell wall?
(a) Gametes
(b) Amoeba
(c) Mycoplasma
(d) All of these

Question. Cell sap is a
(a) living content of cytoplasm.
(b) nonliving content of cytoplasm.
(c) nonliving content of vacuole.
(d) living content of vacuole.

Question. Which of the following is absent in prokaryotes?
(a) DNA
(b) RNA
(c) Plasma membrane
(d) Mitochondria

Directions for below Questions: A student was given cell samples (A and B) to identify parts which are highlighted. He observed the samples under the microscope and list down the function of the part of cell sample. The information collected by the student is listed in the table below, on the basis of which
the student infers that the samples contain the organelles.

Question. Explain why the samples were belonged to eukaryotic cell and not prokaryotic cell? Because,
(a) eukaryotic cell have membrane bound organelles.
(b) eukaryotic cell have non – membrane bound organelles.
(c) eukaryotic cell are smaller and multiply more rapidly than prokaryotic cells.
(d) eukaryotic cell are larger and multiply more rapidly than prokaryotic cells.

Question. The cell theory was given in year 1839 by Schleiden and Schwann. According to this theory all organisms are composed of cell and cells are the basic unit of life.
How did this theory help in the field of science?
(a) It helped to study the working of cells.
(b) It helped in curing diseases caused by cell.
(c) It helped in restating the earlier theories on cell.
(d) It helped in introducing the use of microscopes to study cell.

Diagram Type Questions

Question. Identify the cell organelle given below. Which is an important site of formation of glycoproteins & glycolipids?

(a) Rough endoplasmic reticulum
(b) Smooth endoplasmic reticulum
(c) Golgi body
(d) Mitochondria

Question. The figure below shows the structure of a mitochondrion with its four parts labelled (A), (B), (C) and (D).

Select the part correctly matched with its function.
(a) Part (D): Outer membrane – Gives rise to inner membrane by splitting.
(b) Part (B): Inner membrane – Forms infoldings called cristae.
(c) Part (C): Cristae – Possess single circular DNA molecule and ribosomes.
(d) Part (A): Matrix – Major site for respiratory chain enzymes.

Question. In the given figure of animal cell, one organelle is marked as A. Select the correct identification and function of the organelle ‘A’ from the given option.

(a) Endoplasmic reticulum– Synthesis of lipids.
(b) Mitochondria– Produce cellular energy in the form of ATP.
(c) Golgi body– Provides packaging material.
(d) Lysosomes– Secrete hydrolytic enzymes.