MCQs Class 9th Biology Ch-5 The Fundamental Unit of Life Question 1 Which of the following can be made into crystal? (a) A Bacterium (b) An Amoeba (c) A Virus (d) A Sperm Answer 1 (c) Question 2 A cell will swell up if (a) The concentration of water molecules in the cell is higher than the concentration of water molecules in the surrounding medium (b) The concentration of water molecules in the surrounding medium is higher than water molecules concentration in the cell (c) The concentration of water molecules is the same in the cell and the surrounding medium (d) Concentration of water molecules does not matter Answer 2 (c) Question 3 Chromosomes are made up of (a) DNA (b) protein (c) DNA and protein (d) RNA Answer 3 (c) Question 4 Which of these options are not a function of Ribosomes? (i) It helps in the manufacture of protein molecules (ii) It helps in the manufacture of enzymes (iii) It helps in the manufacture of hormones (iv) It helps in the manufacture of starch molecules (a) (i) and (ii) (b) (ii) and (iii) (c) (iii) and (iv) (d) (iv) and (i) Answer 4 (c) Question 5 Which of these is not related to the endoplasmic reticulum? (a) It behaves as a transport channel for proteins between the nucleus and cytoplasm (b) It transports materials between various regions in the cytoplasm (c) It can be the site of energy generation (d) It can be the site for some biochemical activities of the cell Answer 5 (c) Question 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 a higher concentration of solution through a semipermeable membrane Answer 6 (a) Question 7 Plasmolysis is a plant cell is defined as (a) break down (lysis ) of the plasma membrane in hypotonic medium (b) shrinkage of cytoplasm in hypertonic medium (c) shrinkage of nucleoplasm (d) none of them Answer 7 (b) Question 8 Which of the following are covered by a single membrane? (a) Mitochondria (b) Vacuole (c) Lysosome (d) Plastid Answer 8 (b) Question 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 can make their own structural proteins (c) Mitochondria are said to be the powerhouse of the cell as ATP is generated in them. (d) Cytoplasm is called protoplasm Answer 9 (a) Question 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 to the destruction of the plasma membrane (d) Nucleoid is present inside the nucleoplasm of the eukaryotic nucleus Answer 10 (a) Question 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 11 (c) Question 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 12 (a) Question 13 The undefined nuclear region of prokaryotes is also known as (a) nucleus (b) nucleolus (c) nucleic acid (d) nucleoid Answer 13 (d) Question 14 The cell organelle involved in forming complex sugars from simple sugars are (a) endoplasmic reticulum (b) ribosomes (c) plastids (d) Golgi apparatus Answer 14 (d) Question 15 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 Answer 15 (d) Question 16 Amoeba acquires its food through a process, termed (a) exocytosis (b) endocytosis (c) plasmolysis (d) exocytosis and endocytosis both Answer 16 (b) Question 17 The cell wall of which one of these is not made up of cellulose? (a) Bacteria (b) Hydrilla (c) Mango tree (d) Cactus Answer 17 (a) Question 18 Silver nitrate solution is used to study (a) endoplasmic reticulum (b) Golgi apparatus (c) nucleus (d) mitochondria Answer 18 (b) Question 19 Organelle other than nucleus, containing DNA is (a) endoplasmic reticulum (b) Golgi apparatus (c) mitochondria (d) lysosome Answer 19 (c) Question 20 The kitchen of the cell is (a) mitochondria (b) endoplasmic reticulum (c) chloroplast (d) Golgi apparatus Answer 20 (c) Question 21 Lipid molecules in the cell are synthesized by (a) smooth endoplasmic reticulum (b) rough endoplasmic reticulum (c) Golgi apparatus (d) plastids Answer 21 (a) Question 22 Cell arises from pre-existing cell was stated by (a) Haeckel (b) Virchow (c) Hooke (d) Schleiden Answer 22 (b) Question 23 Cell theory was given by (a) Schleiden and Schwann (b) Virchow (c) Hooke (d) Haeckel Answer 23 (a) Question 24 The only cell organelle seen in a prokaryotic cell is (a) mitochondria (b) ribosomes (c) plastids (d) lysosomes Answer 24 (b) Question 25 Organelle without a cell membrane is (a) ribosome (b) Golgi apparatus (c) chloroplast (d) nucleus Answer 25 (a) Question 26 1 μm is (a) 10–6 m (b) 10–9 m (c) 10–10 m (d) 10–3 m Answer 26 (a) Question 27 Lysosome arises from (a) endoplasmic reticulum (b) Golgi apparatus (c) nucleus (d) mitochondria Answer 27 (b) Question 28 Living cells were discovered by (a) Robert Hooke (b) Purkinje (c) Leeuwenhoek (d) Robert Brown Answer 28 (c) Question 29 Select the odd one out (a) The movement of water across a semi-permeable membrane is affected by the number 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 Answer 29 (d)Short Answer Questions Question 1 Do you agree that "A cell is a building unit of an organism"? If yes, explain why? Answer 1 Hint— cell→ tissue → organ → system → organism Question 2 Why does the skin of your finger shrink when you wash clothes for a long time? Answer 2 This is because the soap solution is very concentrated - Hypertonic solution, so water moves out of the cells of the finger by osmosis. Question 3 Why is endocytosis found in animals only? Answer 3 Hint— Cell wall is absent in animals Question 4 A person takes the concentrated solution of salt, after some time, he starts vomiting. What is the phenomenon responsible for such a situation? Explain. Answer 4 Exosmosis in the intestine causes dehydration Question 5 Name any cell organelle which is non-membranous. Answer 5 Ribosomes Question 6 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. What mechanisms are involved in the absorption of digested food and water? Answer 6 Diffusion and osmosis respectively Question 7 If you are provided with some vegetables to cook. You generally add salt to the vegetables during the cooking process. After adding salt, vegetables release water. What mechanism is responsible for this? Answer 7 Exosmosis Question 8 If cells of onion peel and RBC are separately kept in a 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 8 Hint— (b) Onion peel has a cell wall and RBC does not have a cell wall Question 9 Bacteria do not have chloroplast but some bacteria are photoautotrophic in nature and perform photosynthesis. Which part of the bacterial cell performs this? Answer 9 Hint— Small vesicles associated with the plasma membrane Question 10 Match the following A and B (A) (B) (a) Smooth endoplasmic reticulum (i) Amoeba (b) Lysosome (ii) Nucleus (c) Nucleoid (iii) Bacteria (d) Food vacuoles (iv) Detoxification (e) Chromatin material (v) Suicidal bag and nucleolus Answer 10 a—iv; b—v; c—iii; d—i; e—ii Q