The Fundamental Unit Of Life Class 9 Science Important Questions

Students can read the important questions given below for The Fundamental Unit Of Life Class 9 Science. All The Fundamental Unit Of Life Class 9 Notes and questions with solutions have been prepared based on the latest syllabus and examination guidelines issued by CBSE, NCERT and KVS. You should read all notes provided by us and Class 9 Science Important Questions provided for all chapters to get better marks in examinations. Science Question Bank Class 9 is available on our website for free download in PDF.

Important Questions of The Fundamental Unit Of Life Class 9

Question. Chromosomes are made up of
(a) DNA
(b) protein
(c) DNA and protein
(d) RNA

Question. Which of these options are not a function of Ribosomes?
(i) It helps in manufacture of protein molecules
(ii) It helps in manufacture of enzymes
(iii) It helps in manufacture of hormones
(iv) It helps in manufacture of starch molecules
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (iii) and (iv)
(d) (iv) and (i)

Question. 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

Question. Which of the following can be made into crystal?
(a) A Bacterium
(b) An Amoeba
(c) A Virus
(d) A Sperm

Question. 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

Question. 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

Question. A cell will swell up if
(a) The concentration of water molecules in the cell is higher than the concentration of water molecules in surrounding medium
(b) The concentration of water molecules 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

Question. Which of the following are covered by a single membrane?
(a) Mitochondria
(b) Vacuole
(c) Lysosome
(d) Plastid

Question. 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 through a semipermeable membrane

Question. 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

Question. Cell wall of which one of these is not made up of cellulose?
(a) Bacteria
(b) Hydrilla
(c) Mango tree
(d) Cactus

Question. 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

Question. 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

Question. The undefined nuclear region of prokaryotes are also known as
(a) nucleus
(b) nucleolus
(c) nucleic acid
(d) nucleoid

Question. Which out of the following is not a function of vacuole?
(a) Storage
(b) Providing turgidity and rigidity to the cell
(c) Waste excretion
(d) Locomotion

Question. Cell arises from pre-existing cell was stated by
(a) Haeckel
(b) Virchow
(c) Hooke
(d) Schleiden

Question. Living cells were discovered by
(a) Robert Hooke
(b) Purkinje
(c) Leeuwenhoek
(d) Robert Brown

Question. Silver nitrate solution is used to study
(a) endoplasmic reticulum
(b) golgi apparatus
(c) nucleus
(d) mitochondria

Question. The cell organelle involved in forming complex sugars from simple sugars are
(a) endoplasmic reticulum
(b) ribosomes
(c) plastids
(d) golgi apparatus

Question. Organelle other than nucleus, containing DNA is
(a) endoplasmic reticulum
(b) golgi apparatus
(c) mitochondria
(d) lysosome

Question. Amoeba acquires its food through a process, termed
(a) exocytosis
(b) endocytosis
(c) plasmolysis
(d) exocytosis and endocytosis both

Question. Lipid molecules in the cell are sythesized by
(a) smooth endoplasmic reticulum
(b) rough endoplasmic reticulum
(c) golgi apparatus
(d) plastids

Question. Select the odd one out
(a) The movement of water across a semipermeable membrane is affected by the amount of substances dissolved in it.
(b) Membranes are made 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

Question. The only cell organelle seen in prokaryotic cell is
(a) mitochondria
(b) ribosomes
(c) plastids
(d) lysosomes

Question. Organelle without a cell membrane is
(a) ribosome
(b) golgi apparatus
(c) chloroplast
(d) nucleus

Question. Kitchen of the cell is
(a) mitochondria
(b) endoplasmic reticulum
(c) chloroplast
(d) golgi apparatus

Question. 1 μm is
(a) 10^–6 m
(b) 10^–9 m
(c) 10^–10 m
(d) 10^–3 m

Question. Cell theory was given by
(a) Schleiden and Schwann
(b) Virchow
(c) Hooke
(d) Haeckel

Question. Lysosome arises from
(a) endoplasmic reticulum
(b) golgi apparatus
(c) nucleus
(d) mitochondria

Name the organelles which show the analogy written as under

Question. Transporting channels of the cell __________

Question. Power house of the cell __________

Question. Packaging and dispatching unit of the cell __________

Question. Digestive bag of the cell __________

Question. Storage sacs of the cell __________

Question. Kitchen of the cell __________

Question. Control room of the cell __________

In brief state what happens when

Question. dry apricots are left for sometime in pure water and later transferred to sugar solution?

Question. a Red Blood Cell is kept in concentrated saline solution?

Question. the Plasma-membrane of a cell breaks down?

Question. rheo leaves are boiled in water first and then a drop of sugar syrup is put on it?

Question. golgi apparatus is removed from the cell?

Question. Name any cell organelle which is non membranous.

Question. Why does the skin of your finger shrink when you wash clothes for a long time?
Answer. Soap solution is very concentrated – Hypertonic solution, so water moves out of your finger cells by osmosis.

Question. 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, aminoacids, fatty acids, glycerol etc. What mechanisms are involved in absorption of digested food and water?
Answer. Diffusion and osmosis respectively

Question. Why are lysosomes known as ‘suicide-bags’ of a cell?
Answer. Lysosomes are known as ‘suicide-bags’ because when cell gets damaged during the disturbance in cellular metabolism, lysosomes may burst and the digestive enzymes thus released digest their own cell.

Question. A person takes concentrated solution of salt, after sometime, he starts vomiting. What is the phenomenon responsible for such situation? Explain.
Answer. Swallowing a concentration solution of salt results in exosmosis from cells of the alimentary canal. Due to this, dehydration occurs in the person. As a result, the person starts vomiting.

Question. 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. Exosmosis

Question. Why is endocytosis found in animals only?
Answer. Cell wall is absent in animals. Due to this, movement of substances inside the cells is easier in animals than in plants. Due to this, endocytosis is found in animals only.

Question. Do you agree that “A cell is a building unit of an organism”. If yes, explain why?
Answer. I agree with the statement that “A cell is a building block of an organism”. This is true because all living beings are made up of cells and cell is the smallest independent unit of living beings.

Question. Bacteria do not have chloroplast but some bacteria are photoautorophic in nature and perform photosynthesis. Which part of bacterial cell performs this?
Answer. Small vesicles which are associated with plasma membrane are present in such bacteria. These vesicles contain pigments which can trap solar energy to produce food.

Question. 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. (c) a and b both are correct. When surrounding medium is hypotonic, water moves into the cells. This will result in swelling of cells. RBCs do not have cell wall and hence they will easily burst. Presence of cell wall in the cells of onion peel will prevent their bursting.

Question. Match the following A and B
Answer. a—(iv); b—(v); c—(iii); d—(i); e—(ii).

Question. How is a bacterial cell different from an onion peel cell?
Answer.

Question. How do substances like carbon dioxide (CO₂) and water (H₂O) move in and out of the cell?
Answer. Carbon dioxide moves through diffusion, while water moves through osmosis.

Question. Draw a plant cell and label the parts which
(a) determines the function and development of the cell
(b) packages materials coming from the endoplasmic reticulum
(c) provides resistance to microbes to withstand hypotonic external media without bursting
(d) is site for many biochemical reactions necessary to sustain life.
(e) is a fluid contained inside the nucleus
Answer. (a) Nucleus
(b) Golgi apparatus
(c) Cell wall
(d) Cytoplasm
(e) Nucleoplasm.

Question. Name the two organelles in a plant cell that contain their own genetic material and ribosomes.
Answer. Mitochondria and plastids

Question. Write the name of different plant parts in which chromoplast, chloroplast and leucoplast are present.
Answer. Flower and Fruit— Chromoplast
Leaves of the plant— Chloroplast
Root of the plant— Leucoplast

Question. How does amoeba obtain its food?
Answer. Amoeba makes pseudopodia to surround a food particle. It then ingest the food particles; along with a drop of water and then forms food vacuole. This process of obtaining food by Amoeba is called endocytosis.

Question. Why are lysosomes also known as “scavengers of the cells”?
Answer. Lysosomes contain enzymes which are used for destroying worn out parts of the cell. Lysosomes also destroys waste materials. Due to this, lysosomes are also known as ‘scavengers of the cells’.

Question. Why do plant cells possess large sized vacuole?
Answer. Vacuoles not only store many important substances, they also contain cell sap that give turgidity to cell.

Question. How are chromatin, chromatid and chromosomes related to each other?
Answer. Chromosomes are made up of chromatids and chromatids are made up of chromatin.

Question. Which cell organelle controls most of the activities of the cell?
Answer. Nucleus

Question. What are the consequences of the following conditions?
(a) A cell containing higher water concentration than the surrounding medium
(b) A cell having low water concentration than the surrounding medium.
(c) A cell having equal water concentration to its surrounding medium.
Answer. (A) Exosmosis
(B) (Endosmosis
(C) No effect

Question. Draw a neat diagram of plant cell and label any three parts which differentiate it from animal cell.
Answer.

Question. Illustrate only a plant cell as seen under electron microscope. How is it different from animal cell?
Answer.

Question. Which kind of plastid is more common in
(a) roots of the plant
(b) leaves of the plant
(c) flowers and fruits
Answer. (A) Leucoplast
(B) Chloroplast
(C) Chromoplast

Question. Draw a well labelled diagram of an eukaryotic nucleus. How is it different from nucleoid?
Answer.

Question. Differentiate between rough and smooth endoplasmic reticulum. How is endoplasmic reticulum important for membrane biogenesis?
Answer. The ribosomes, which are present in all active cells, are the sites of protein synthesis. Endoplasmic reticulum helps in transporting these proteins to various places. The smooth endoplasmic reticulum help in manufacture of fat and lipids which along with proteins help in building the cell membrane.

Question. Draw a neat labelled diagram of an animal cell.
Answer.