NCERT Exemplar Solution Class 9 Science Chapter 5
NCERT Exemplar Solution Class 9 Science Chapter 5 The Fundamental Unit Of Life all Questions Answer Solution. NCERT Exemplar Class 9 Science Chapter 5 Solution PDF.
NCERT Exemplar Solution Class 9 Science Chapter 5: Overview
NCERT Exemplar Solution Class 9 Science Chapter 5 |
|
Board |
NCERT |
Topic |
Exemplar Problem Solution |
Class |
9 |
Subject |
Science |
Chapter |
5 |
Chapter Name |
The Fundamental Unit Of Life |
Multiple Choice Questions
1) Which of the following can be made into crystal?
a) A bacterium
b) An amoeba
c) A virus
d) A sperm
Answer:- c) A virus
Explanation: Virus are not completely living. These cannot reproduce with itself. These needs support of a host cell to reproduce. These viruses can be stored for longer time in the form crystals.
2) A Cell wall swell up if
a) The concentration of water in the cell is higher than the concentration of water molecules in surrounding medium.
b) The concentration of water in surrounding medium is higher than water molecules concentration in the cell.
c) The concentration of water molecules is same in the cell and in the surrounding medium.
d) Concentration of water molecules does not matter.
Answer:- b) The concentration of water in surrounding medium is higher than water molecules concentration in the cell.
Explanation: These process is known as Osmosis. Where the water transfer from higher concentration to the lower concentrations. Osmosis leads to the swelling of cell wall.
3) Chromosomes are made up of
a) DNA
b) Protein
c) DNA and protein
d) RNA
Answer:- c) DNA and protein
Explanation: Chromosomes containsDNA and protein both. These are also known as carrier of hereditary characters. Which is in the DNA.
4) Which of these options are not a function of ribosomes ?
I)It helps in manufacturer of protein molecules
II)It helps in manufacturer of enzymes
III)It helps in manufacturer of hormones
IV)It helps in manufacturer of starch molecules
a) I and II
b) II and III
c) III and IV
d) IV and I
Answer:- c) III and IV
Explanation: Manufacturing of hormones and manufacturing of starch Molecules are not the function of Ribosomes.Because ribosome are protein factories. It helps in the formation of protein. And hormones are also one type of protein. Thus the Ribosomes are manufacturer of protein and also hormones.
5) Which of these is not related to endoplasmic reticulum?
a) It behaves as Transport channel for proteins between nucleus and cytoplasm.
b) It transports materials between various regions in cytoplasm
c) It can be the site of energy generation
d) It can be the site for some biochemical activities of the cell
Answer:- c) it can be the site of energy generation
Explanation: Energy generation is not the function of Endoplasmic reticulum. Mitochondria is responsible for the generation of energy. And thus it is called as power house of the cell.
6) Following are a few definitions of osmosis.
Read carefully and select the correct definition.
a) Movement of water molecules from a region of higher concentration to a region of lower concentration through a semipermeable membrane.
b) Movement of solvent molecules from its higher concentration to lower concentration.
c) Movement of solvent molecules from higher concentration to lower concentration of solution through a permeable membrane.
d) Movement of solute molecules from lower concentration to higher concentration of solution thorough a semipermeable membrane.
Answer:-
b) movement of solvent molecules from its higher concentration to lower concentration .
Explanation: The correct definition of the osmosis is the movement of solvent molecules from Higher concentration to lower concentration. It is also one type of diffusion and the movement can be done through an semipermeable membrane.
7) Plasmolysis in a plant cell is defined as
a) Break down (lysis) of plasma membrane in hypotonic medium
b) Shrinkage of cytoplasm in hypertonic medium.
c) Shrinkage of nucleoplasm
d) None of them
Answer:- b) shrinkage of cytoplasm in hypertonic medium.
Explanation: Plasmolysis is the process in which the cells loses their water from inside to outside by osmosis and thus it gets shrink. In hypertonic medium outer part of cell has low water concentration than the cell. Thus there is shrinkage of cytoplasm .
8) Which of the following are covered by a single membrane?
a) Mitochondria
b) Vacuole
c) Lysosome
d) Plastid
Answer:-c) Lysosome
Explanation: All othergiven options have double layered covering while the lysosome has only single layered covering.
9) Find out the false sentences.
a) Golgi apparatus is involved with the formation of lysosomes.
b) Nucleus, mitochondria and plastid have DNA ; hence they are able to make their own structural proteins
c) Mitochondria is said to be the power house of the cell as ATP is generated in them.
d) Cytoplasm is called as protoplasm.
Answer:- a) Golgi apparatus is involved with the formation of lysosomes.
Explanation: Golgi apparatus does bot involved in the formation of lysosomes. They perform the function of storage and synthesis of some chemical biomolecules. Therefore it is the wrong statement.
10) Find out the correct sentence.
a) Enzymes packed in lysosomes are made through RER(Rough Endoplasmic Reticulum)
b) Rough Endoplasmic Reticulum and smooth endoplasmic reticulum produce lipid and protein respectively.
c) Endoplasmic Reticulum is related with the destruction of plasma membrane.
d) Nucleoid is present inside the nucleoplasm of eukaryotic nucleus.
Answer:- a) Enzymes packed in lysosomes are made through RER (Rough endoplasmic Reticulum)
Explanation: Endoplasmic reticulum perform the function of Synthesis of proteins. As they are called as protein factories. Ribosomes has endoplasmic reticulum over it thus it is known as Rough endoplasmic reticulum. Therefore enzymes which are protein are packed in Ribosome which are formed by RER.
11) Which cell organelle plays a crucial role in detoxifying many poisons and drugs in a cell?
a) Golgi apparatus
b) Lysosomes
c) Smooth endoplasmic reticulum
d) Vacuoles
Answer:- c) smooth endoplasmic Reticulum
Explanation: Smooth endoplasmic Reticulum play an important role in detoxifying many poisons and drugs in the cells.
12) The proteins and lipids, essential for building the cell membrane, are manufactured by
a) Rough endoplasmic reticulum
b) Golgi apparatus
c) Plasma membrane
d) Mitochondria
Answer:- a) Rough endoplasmic reticulum
Explanation: Rough endoplasmic reticulum are known as protein factories. These does the work of making protein and lipids.
13) The undefined nuclear region of Prokaryotes are also known as
a) Nucleus
b) Nucleolus
c) Nucleic acid
d) Nucleoid
Answer:- d) Nucleoid
Explanation: Prokaryotes does not have well organised Nucleus and thus it does not have well nucleoid.
14) The cell organelle involved in forming complex sugars from simple sugars are
a) Endoplasmic Reticulum
b) Ribosomes
c) Plastids
d) Golgi apparatus
Answer:-d) Golgi apparatus
Explanation: Golgi apparatus is involved in the forming of complex augers from simple sugars. These are also perform the function of packaging of protein and lipids and other Molecules.
15) Which of the following is not a function of vacuole?
a) Storage
b) Providing turgidity and rigidity to the cell
c) Waste excretion
d) Locomotion
Answer:- d) Locomotion
Explanation: Locomotion is the movement from place to another place. Vacuoles perform the function of storage, provides turgidity and rigidity to the cell, and excretion of waste.
16) Amoeba acquires its food through a process, termed
a) Exocytosis
b) Endocytosis
c) Plasmolysis
d) Exocytosis and endocytosis both
Answer:- b) Endocytosis
Explanation: Endocytosis is the process in which the substances present out of the cell are taken in through the Vacuoles, amoeba takes in the food by the Endocytosis.
17) Cell wall of which one of these is not made up of cellulose?
a) Bacteria
b) Hydrilla
c) Mango
d) Cactus
Answer:- a) Bacteria
Explanation: Bacteria’s cell wall is not made up of cellulose it is made up of peptidoglycan. other all have cell wall of cellulose.
18) Silver nitrate solution is used to study
a) Endoplasmic Reticulum
b) Golgi apparatus
c) Nucleus
d) Mitochondria
Answer:- b) Golgi apparatus
Explanation: Silver nitrate ( AgNo3 ) Solution is used for the study the Golgi apparatus.
19) Organelle other than nucleus, containing DNA is
a) Endoplasmic Reticulum
b) Golgi apparatus
c) Mitochondria
d) Lysosome
Answer:- c) Mitochondria
Explanation: Mitochondria and also Chloroplast contain DNA other than Nucleus.
20) Kitchen of the cell is
a) Mitochondria
b) Endoplasmic Reticulum
c) Chloroplast
d) Golgi apparatus
Answer:- c) Chloroplast
Explanation: All the food making process is carried out in the chloroplast cell of the plant which is present in the leaves of the plants.
21) Lipid molecules in the cell are synthesized by
a) Smooth endoplasmic Reticulum
b) Rough endoplasmic Reticulum
c) Golgi apparatus
d) Plastids
Answer:- a) smooth endoplasmic reticulum
Explanation: Smooth endoplasmic Reticulum synthesis the lipid and rough endoplasmic reticulum synthesis the protein molecules.
22) Cell arises from pre- existing cell was stated by
a) Haeckel
b) Virchow
c) Hooke
d) Schleiden
Answer:- b) Virchow
Explanation: Virchow discovered that cell arises from pre- existing cell.
23) Cell theory was given by
a) Schleiden and Schwann
b) Virchow
c) Hooke
d) Haeckel
Answer:- a) Schleiden and Schwann
Explanation: Schleiden and Schwann propose the cell theory in plants first time. Later Robert Hooke discovered cell.
24) The only cell organelle seen in prokaryotic cell is
a) Mitochondria
b) Ribosomes
c) Plastids
d) Lysosomes
Answer:- b) Ribosomes
Explanation: Prokaryotes does not contain all the cell organelle, it is primitive cell, it is present in single celled organisms. Which contains ribosomes but not the Mitochondria, plastids and lysosomes
25) Organelle without a cell membrane is
a) Ribosome
b) Golgi apparatus
c) Chloroplast
d) Nucleus
Answer:- a) Ribosome
Explanation: Ribosomes does not contain cell membrane while the other Golgi apparatus, chloroplast and nucleus have double layered cell membrane.
26) 1 um is
a) 10 -6 m
b) 10 -9 m
c) 10 -10 m
d) 10 -3 m
Answer:-
a) 10-6 m
10-6 m = 1um
10-9 m= 1nm
10-10 m = 1dm
10-3 m = 1 mm
27) Lysosome arises from
a) Endoplasmic Reticulum
b) Golgi apparatus
c) Nucleus
d) Mitochondria
Answer:- b) Golgi apparatus
Explanation: Lysosomes formed from the Golgi bodies, these are small sac like Vacuoles containing hormones which kills the dead and worn out cells. These are also known as suicidal bags.
28) Living cells were discovered by
a) Robert Hooke
b) Purkinje
c) Leeuwenhoek
d) Robert Brown
Answer:- c) Leeuwenhoek
Explanation: Schleiden and Schwann propose the cell theory, Robert Hooke discovered cell and Leeuwenhoekdiscovered the living cells for the first time.
29) Select the odd one out
a) The movement of water across a semi permeable membrane is affected by the amount of substances dissolved in it.
b) Membranes are made up of organic molecules like Proteins and lipids.
c) Molecules soluble in organic solvents can easily pass through the membrane.
d) Plasma membranes contain chitin sugar in plants.
Answer:- d) plasma membrane contain chitin sugar in plants.
Explanation: Option d) is odd one because all the other sentences are correct but the d is wrong statement. Plasma membrane does not contain chitin sugar it contains cellulose.
Short Answer Questions
30) Why are lysosomes known as ‘suicide – bags’ of a cell?
Answer:-
Lysosomes are the cell organelle which is also known as suicidal bags .because these are Vacuoles which are filled with a enzymes. These is digestive enzymes. These lysosomes mainly perform the function of waste disposal of the cells. i.e. digesting the dead cells or killing the damaged cells. During killing the other damaged cells these lysosomes burst and all the digestive enzymes inside it kill the cell. But due to these the lysosome also killed itself thus it is known as suicidal bags.
31) Do you agree that “ A cell is a building unit of an organism”, if yes, explain why?
Answer:-
Yes, cells are also called as building element of an organism. Cells are basic functional unit of Life and living organisms. Cells gathered together to form tissues, tissues form organs, organs form organ system, and finally organ system leads to the formation of living organisms.
32) Why does the skin of your finger shrink when you wash clothes for a long time?
Answer:-
Cells of Skin of our finger goes through the osmosis process when we wash clothes for long time, due to the concentrated soap solution which is hypertonic in nature the water from cells of the fingers move out and the skin shrinks.
33) Why is endocytosis found in animals only?
Answer:-
Endocytosis is the process of movement of substances from outside to inside the cellswhich is carried out only in animals. Because there is a difference between plant cell and animal cell is that animal cell does not have cell wall. Cell wall is only present in plant cell, and not in animals. Thus it is smoothly carried out in animals.
34) A person takes concentrated solution of salt, after sometime, he starts vomiting. What is the phenomenon responsible for such situation? Explain.
Answer:- Salt solution is concentrated solution which on consuming occurs Exosmosis. The process of Exosmosis carried out in the stomach and intestine ,Due to these the person started vomiting.
35) Name any cell organelle which is non Membranous.
Answer:- Ribosomes is the cell organelle which is non Membranous.
36) We eat food composed of all the nutrients like carbohydrates, proteins, fats, vitamins, minerals, and water. After digestion, these are absorbed in the form of glucose, amino acids, fatty acids, glycerol etc.
Answer:- The absorption process of nutrients is done with the help of process of diffusion which us carried out in stomach. After the absorption, digestion is carried out by the process of Osmosis process. These digestion or osmosis is carried out in intestine.
37) If you are provided with some vegetables to cook. You generally add salt into the vegetables during cooking process. After adding salt, vegetables release water. What mechanism is responsible for this?
Answer:- AddingSalt becomes hypertonic in nature. Due to these when salt is added to vegetablesthe surrounding of vegetables becomes hypertonic, and to maintain the equilibrium vegetables release water. And these process is known as Exosmosis.
38) If cells of onion peel and RBC are separately kept in hypotonic solution, what among the following will take place? Explain the reason for your Answer.
a) Both the cells will swell.
b) RBC will burst easily while cells of onion peel will resist the bursting to some extent.
c) A and B both are correct.
d) RBC and Onion peel cells will behave similarly.
Answer:-
Answer is c) A and B both are correct.
Here, both the cells will swell. But RBC will burst easily while the onion peel will resist to some extent. Because onion peel which is a plant cell have an cell wall which resist the bursting of cell to some extent. But RBC which is animal cell it does not have cell wall therefore it burst easily.
39) Bacteria do not have chloroplast but some bacteria are photoautotrophic in nature and perform photosynthesis. Which part of bacteria cell performs this?
Answer:- Bacteria do not have Chloroplast but bacteria have small vesicles. These vesicles are associated with plasma membrane. The pigments present in vesicles traps the sunlight. And the photosynthesis is carried out in the bacteria. Thus how some bacteria are photoautotrophic in nature.
40) Match the following A and B
(A) |
Answers |
a) Smooth endoplasmic Reticulum | iv) detoxification |
b) Lysosomes | v) suicidal bags |
c) Nucleoid | iii) Bacteria |
d) Food vacuoles | ii) Nucleus |
e) Chromatin material and Nucleolus | i) Amoeba |
41) Write the name of different plant parts in which chromoplast, chloroplast, and leucoplast are present.
Answer:-
The parts of plant in which chromoplast, chloroplast and leucoplast are present are as follows-
1) Chromoplast- Fruits and flowers
2) Chloroplast – leaves
3) Leucoplast – Roots
42) Name the organelles which show the analogy written as under
a) Transportingchannels of the cell ____________.
Answer:- Transporting channels of the cell Endoplasmic Reticulum.
b) Power house of the cell________
Answer:- Power House of the cell mitochondria.
c) Packaging and dispatching unit of the cell _________.
Answer:- packaging and dispatching unit of the cell Golgi body.
d) Digestive bag of the cell _________
Answer:- digestive bag of the cell Lysosomes.
e) Storage sacs of the cell_________
Answer:- storage sacs of the cell Vacuoles
f) Kitchen of the cell _________
Answer:- kitchen of the cell Chloroplast
g) Control room of the cell ________
Answer:- Control room of the cell Nucleus.
43) How is a bacterial cell different from an onion peel cell ?
Answer:- Bacterial cell is different from an onion peel cell in the form of following reasons.
1) Bacterial cell is prokaryotic cell while the onion peel cells are Eukaryotic cell.
2) Bacterial cell does not have well organised Nucleus in it while the onion peel cell have well organised Nucleus.
3) Bacterial cell lack in membranes bound organelles on the other hand onion peel cell have membrane bound organelles.
4) Nucleolus is absent in bacteria and it is present in onion peel cells.
44) How do substances like carbon dioxide (CO2) and water (H2O) move in and out of the cell?
Answer:- The process of Osmosis and diffusion plays an important role in the Moving in and out of the substances like Carbon dioxide and water from the cell.
45) How does amoeba obtain it’s food?
Answer:- Endocytosisis the process of by which amoeba takes in the food. It is carried out through pseudopodia. Pseudopodia of amoeba is also responsible for locomotion.
46) Name the two organelles in a plant cell that contain their own genetic material and ribosomes..
Answer:- mitochondria and Chloroplast Are the two cell organelles in plant cell which contains their own genetic material and Ribosomes. It is known as MitochondriaDNA and Chloroplast DNA.
47) Why are lysosomes also known as “ Scavengers of the cells?”
Answer:- Lysosomes are the waste disposal of the cell these perform the function of Removing waste of debris from the cell. The damaged cells are killed and removed out of cell by lysosomes . Therefore it is known as scavengers of the cells.
48) Which cell organelle control most of the activities of the cell?
Answer:- Nucleus Is the main part of the cell. Nucleus is the heart of the cell. Which controls all the activities of the cell.
49) Which kind of plastid is more common in
a) Roots of the plant
Answer:- leucoplast plastid is most common in Roots of plant.
b) Leaves of the plant
Answer:- chloroplast plastid is most common in leaves of the plant.
c) Flowers and fruits
Answer:- chromoplast is the plastid which is more common in flowers and fruits.
50) Why do plant cells posses large sized vacuole ?
Answer:- Plant cells posses large sized Vacuoles for the storage of food and nutrients necessary for cells. It also contains cell sap in vacuole. Which helps in the maintaining the turgidity of the cell.
51) How are chromatin, chromatid and Chromosomes related to each other ?
Answer:- Yes. All of these are related to the each other. Chromatin are small thread like structures which comes together to form chromatids. Chromatids have two parts which are jointed by centromere. These are similar to chromosome. Chromatids further form the Chromosomes. These chromosomes are Rod like bodies which contains DNA in it.
52) What are the consequences of the following conditions?
a) A cell containing higher water concentration than the surrounding medium.
Answer:- Exosmosisprocess will carried out when cell has higher water concentration than the surrounding the cell will loose water and shrink.
b) A cell having low water concentration than the surrounding medium.
Answer:- Endosmosisprocess will be performed when cell has low water concentration than surrounding medium. And the cell will swollen up.
c) A cell having equal water concentration to its surrounding medium.
Answer:- there will not be any effect over the cell because equilibrium of water is maintained inside and outside of the cell.
Long Answer Questions
53) Draw a plant cell and label the parts which
a) Determines the function and development of the cell
Answer:- Nucleus Determines the function and development of the cell.
b) Package materials coming from the Endoplasmic Reticulum
Answer:- Golgi apparatus is the cell organelle which comes out from endoplasmic Reticulum.
c) Provides resistance to microbes to withstand hypotonic external media without bursting.
Answer:- Cell wall provides resistance to the pathogens and Microbes.
d) Is site for many biochemical reactions necessary to sustain life.
Answer:-.Cytoplasm is the site of many biochemical reactions which are necessary.
e) Is a fluid contained inside the nucleus.
Answer:-Nucleoplasm is the fluid inside the nucleus.
54) Illustrate only a plant cell as seen under electron microscope. How is it different from animal cell?
Answer:-
A. Cell wall is absent in animal cell and it is present in plant cell.
B. Chloroplast is present in plant cell but absent in animal cell.
C. Large vacuoles are present in plant cell but it is absent in animal cell.
55) Draw a neat labelled diagram of an animal cell.
Answer:-
Diagrammatic representation of Animal cell
56) Draw a well labelled diagram of an eukaryotic nucleus. How is it different from nucleoid?
Answer:-
Eukaryotic nucleus is well organised Nucleus. It contains all the cell organelles properly arranged and functionally well. Nucleus of the Eukaryotic cellis large in size. While the nucleoid are the small spots like granules which are embedded over the cytoplasm. Nucleoid are small in size and contains single DNA. While the nucleus is large and contains many DNA.
The figure of The nucleus of Eukaryotic cell is as shown below-
57) Differentiate between rough and smooth endoplasmic reticulum. How is Endoplasmic Reticulum important for membrane biogenesis?
Answer:-
Smooth endoplasmic Reticulum | Rough endoplasmic Reticulum |
· It is known As smooth endoplasmic Reticulum | It is known as Rough endoplasmic reticulum |
· These are Smooth because they don’t have Ribosomes over the body. | They are rough because they have Ribosomes over the body. |
· Therefore it appears smooth under the microscope | Therefore it appears rough under the microscope. |
· Smooth endoplasmic Reticulum helps in the synthesis of fat molecules or lipids. | Rough endoplasmic reticulum helps in the synthesis of proteins. |
· These helps in the detoxification of the drugs in the liver cells of the vertebrae. | These are transporters of the proteins to another cell organelles. |
58) In brief state what happens when
a) Dry apricots are left for sometime in pure water and later transferred to sugar solution?
Answer:- when the dried apricots are kept in the water it will swell after some time, as it goes through the osmosis process, As water moves from higher concentration to the lower concentration. But when these are transferred to the concentrated sugar solution it will loose water and shrink in size and goes through reverse osmosis. The water moves from lower concentration to the higher concentrations.
b) A Red Blood Cell is kept in concentrated saline solution?
Answer:- if the Red blood cell kept in concentrated saline solution then the cell will loose all the water and shrink in size due to reverse osmosis. As the water moves from cell to the outsideinto saline. I.e from lower concentration to the higher concentration.
c) The plasma – membrane of a cell breaks down?
Answer:-
Plasma membrane is the protective covering of the cell. It protects from the outer harmful particles to move inside the cell. If the plasma membrane will removed from the cell the cell will die.
d) Rheo leaves are boiled in water first and then a drop of sugar syrup is put on it?
Answer:-
On the boiling cells of the leaves will die, then putting a drop of sugar syrup on it will not work because cell will not perform the osmosis process well.
e) Golgi apparatus is removed from the cell?
Answer:- if the Golgi apparatus is removed from the cell then cell will not perform the function of the packaging of protein, lipids, carbohydrates and other biomolecules also cell will not be able to transport it.
59) Draw a neat diagram of plant cell and label any three parts which differentiate it from animal cell.
Answer:-