WBBSE Class 9 Life Science And Environment Chapter 2 Organic And Inorganic Molecules Multiple Choice Questions

Chapter 2 Levels Of Organization Of Life Organic And Inorganic Molecules Summary Multiple Choice Questions

Question 1. The most abundant element within a living body is

  1. Carbon, water, and oxygen
  2. Carbon and nitrogen
  3. Water.
  4. Oxygen, hydrogen, carbon, and nitrogen

Answer: 4. Oxygen, hydrogen, carbon, and nitrogen

Question 2. In plants, the medium of transport is

  1. Water
  2. Phloem
  3. Xylem
  4. Both A and B

Answer: 1. Water

Question 3. HCI in the stomach helps in the digestion of

  1. Protein
  2. Lactose
  3. Maltose
  4. Fructose

Answer: 1. Lactose

Question 4. Acidic chyme in the stomach is neutralized by

  1. Bile salt
  2. Sodium bicarbonate
  3. NaOH
  4. KOH

Answer: 2. Sodium bicarbonate

WBBSE Class 9 Life Science And Environment Chapter 2 Organic And Inorganic Molecules mcqs

WBBSE Class 9 Organic and Inorganic Molecules MCQs

Question 5. Which of the following is not a strong acid?

  1. HNO3
  2. HCI
  3. H2CO3
  4. H2SO4

Answer: 3. H2CO3

WBBSE Class 9 Life Science Question And Answer

Question 6. An example of weak alkali is

  1. NH4OH
  2. NaOH
  3. KOH
  4. None of these

Answer: 1. NH4OH

Question 7. The percentage of mineral salts present in cellular components is

  1. 10-30%
  2. 1-3%
  3. 0.1-0.3%
  4. 0.01-0.03%

Answer: 2. 1-3%

Question 8. A biomacromolecule is

  1. Glucose
  2. Peptide
  3. Lipid
  4. Protein

Answer: 1. Glucose

Important MCQs on Organic Molecules for Class 9

Question 9. Which one is an organic acid?

  1. h2so4
  2. hno3
  3. HCI
  4. Maleic acid

Answer: 4. Maleic acid

Question 10. Which of the following is not an organic macromolecule?

  1. DNA
  2. RNA
  3. Nucleotide
  4. Protein

Answer: 3. Nucleotide

WBBSE Class 9 Life Science Question And Answer

Question 11. The main energy-generating biomolecule is

  1. Protein
  2. Carbohydrate
  3. Fat
  4. Vitamin

Answer: 2. Carbohydrate

Question 12. In which of the following biomolecules do carbon, hydrogen, and oxygen maintain a ratio of 1:2:1?

  1. Nucleotide
  2. Protein
  3. Fatty acid
  4. Carbohydrate

Answer: 4. Carbohydrate

Question 13. The simple structural formula of carbohydrates is

  1. cn(H2O)n-1
  2. (C6H10O5)n
  3. (CH20)n
  4. R-COOH

Answer: 3. (C6H10O5)n

Inorganic Molecules MCQs for Class 9 Life Science

Question 14. The simplest form of sugar is

  1. Glucose
  2. Sucrose
  3. Cellulose
  4. Lactose

Answer: 1. Glucose

Question 15. Which of the following is not a hexose sugar?

  1. Glucose
  2. Galactose
  3. Ribose
  4. Fructose

Answer: 3. Ribose

Question 16. Which of the following carbohydrates is not a keto sugar?

  1. Erythrose
  2. Fructose
  3. Xylulose
  4. Ribulose

Answer: 1. Erythrose

Question 17. The main sugar present in honey is

  1. Glucose
  2. Fructose
  3. Sucrose
  4. Maltose

Answer: 2. Fructose

Question 18. The sugar present in sugarcane juice is

  1. Fructose
  2. Glucose
  3. Maltose
  4. Sucrose

Answer: 2. Sucrose

Question 19. Commonly used table sugar is

  1. Maltose
  2. Lactose
  3. Sucrose
  4. Glucose

Answer: 3. Sucrose

Question 20. The sugar present in the ONA molecule is composed of

  1. 6-Carbon
  2. 5-Carbon
  3. 4-Carbon
  4. 1-Carbon

Answer: 2. 5-Carbon

Practice MCQs for Class 9 Life Science Chapter 2

Question 21. Besides the amino group, the other functional group present in an amino acid is

  1. Hydroxyl group
  2. Carboxyl group
  3. Aldehyde group
  4. Ketone group

Answer: 2. Carboxyl group

Question 22. The number of amino acids taking part in protein synthesis is

  1. 10
  2. 20
  3. 30
  4. 40

Answer: 2. 20

Question 23. An essential amino acid is

  1. Valine
  2. Glutamic acid
  3. Argentine
  4. Glycine

Answer: 1. Valine.

Question 24. The simple structural formula of an amino acid is

  1. R-CHNH2COOH
  2. NH2-R = CO
  3. R-COOK
  4. R-NH2

Answer: 1. R-CHNH2COOH

Question 25. A sulfur-containing amino acid is

  1. Serine
  2. Valine
  3. Methionine
  4. Isoleucine

Answer: 2. Methionine

Question 26. A hydrophobic amino acid is

  1. Leucine
  2. Tyrosine
  3. Histidine
  4. Serine

Answer: 1. Leucine

Question 27. The two functional groups present in amino acids are

  1. Amin and Ketone
  2. Amino and Carboxyl
  3. Amino and Aldehyde
  4. Amino and Hydroxyl

Answer: 2. Amino and Carboxyl

West Bengal Board Class 9 Life Science Book Solution

Question 28. The important structural element of amino acids is

  1. N
  2. O
  3. H
  4. Na

Answer: 1. N

Question 29. Each fatty acid has a hydrocarbon chain ending with

  1. Hydroxyl group
  2. Aldehyde group
  3. Ketone group
  4. Carboxyl group

Answer: 4. Carboxyl group

Question 30. Carboxyl group An essential fatty acid is

  1. Stearic acid
  2. Oleic acid
  3. Linolenic acid
  4. All of these

Answer: 3. Linolenic acid

Key Concepts for MCQs on Organic and Inorganic Molecules

Question 31. A chromosome is a

  1. Combination of many nucleotides
  2. Nucleoprotein substance
  3. Combination of many proteins
  4. Combination of proteins and lipids

Answer: 1. Combination of many nucleotides

Question 32. Which of the following share the same class with glucose, sucrose, and maltose?

  1. Myoglobin
  2. Amino acid
  3. Starch
  4. Haemoglobin

Answer: 3. Starch

Question 33. Glycogen and starch are

  1. Monosaccharides
  2. Disaccharides
  3. Oligosaccharides
  4. Polysaccharides

Answer: 4. Polysaccharides

Question 34. A starch molecule is formed by combining

  1. Glucose
  2. Maltose
  3. Galactose
  4. Lactose

Answer: 1. Glucose

West Bengal Board Class 9 Life Science Book Solution

Question 35. The monosaccharide present in glycogen is

  1. Fructose
  2. Cellulose
  3. Glucose
  4. Galactose

Answer: 3. Glucose

Question 36. In which organ is glucose stored as glycogen?

  1. Pancreas
  2. Liver
  3. Spleen
  4. Kidney

Answer: 2. Liver

Question 37. Which of the following carbohydrates can be not digested in the human intestine?

  1. Glycogen
  2. Cellulose
  3. Maltose
  4. Inulin

Answer: 2. Cellulose

Question 38. The walls of the xylem become rigid due to the presence of

  1. Glycogen
  2. Chitin
  3. Cellulose
  4. Lignin

Answer: 4. Lignin

Sample MCQs from WBBSE Class 9 Life Science

Question 39. The main component of plant cell wall is—

  1. Cellulose
  2. Glycogen
  3. Glucose
  4. Lipid and protein

Answer: 1. Cellulose

Question 40. The main component of fungal cell wall is—

  1. Inulin
  2. Chitin
  3. Cellulose
  4. Pectin

Answer: 2. Chitin

Question 41. Which of the following is known as animal starch?

  1. Glucose
  2. Cellulose
  3. Inulin
  4. Glycogen

Answer: 4. Glycogen

Question 42. The structural component of a simple protein molecule is—

  1. Peptide
  2. Peptone
  3. Amino acid
  4. Nucleic acid

Answer: 1. Peptide

Question 43. Which of the following compounds is essentially a protein structure?

  1. Hormone
  2. Enzyme
  3. Co-enzyme
  4. Prostaglandin

Answer: 2. Enzyme

Question 44. The two radicals present in protein molecules are—

  1. Amino and ketone
  2. Amino and carboxyl
  3. Carboxyl and aldehyde
  4. Aldehyde and ketone

Answer: 2. Amino and carboxyl

West Bengal Board Class 9 Life Science Book Solution

Question 45. Which of the following is a simple protein?

  1. Haemoglobin
  2. Nucleoprotein
  3. Glycoprotein
  4. Globulin

Answer: 4. Globulin

Question 46. The bond present in protein molecules is—

  1. Covalent bond
  2. Peptide bond
  3. Electrovalent bond
  4. Glycosidic bond

Answer: 2. Peptide bond

Question 47. Which of the following is produced after the hydrolysis of a polypeptide?

  1. Fatty acid
  2. Amino acid
  3. Lactic acid
  4. Nucleic acid

Answer: 2. Amino acid

Question 48. Which is not a conjugated protein?

  1. Proteose
  2. Nucleoprotein
  3. Metalloprotein
  4. Glycoprotein

Answer: 1. Proteose

Question 49. Haemoglobin is a—

  1. Simple protein
  2. Conjugated protein
  3. Derived protein
  4. Colloidal protein

Answer: 2. Conjugated protein

Question 50. The protein component of a hemoglobin molecule is

  1. Haem
  2. Globin
  3. Both
  4. None of these

Answer: 2. Globin

Question 51. The non-protein component of a hemoglobin molecule is

  1. Magnesium
  2. Calcium
  3. Copper
  4. Iron

Answer: 4. Iron

Question 52. Which of the following is not a fibrous protein?

  1. Haemoglobin
  2. Elastin
  3. Keratin
  4. Elastin

Answer: 2. Elastin

Question 53. Which has a close association with fibrous protein?

  1. Centrosome
  2. Golgi body
  3. Endoplasmic reticulum
  4. Mitochondria

Answer: 1. Centrosome

West Bengal Board Class 9 Life Science Book Solution

Question 54. Which is a chromoprotein?

  1. Gleadin
  2. Keratin
  3. Haemoglobin
  4. Elastin

Answer: 3. Haemoglobin

Question 55 An example of contractile protein is

  1. Keratin
  2. Collagen
  3. Haemoglobin
  4. Myosin

Answer: 4. Myosin

Question 56. One useful lipoprotein for humans is

  1. LDL
  2. HDL
  3. VLDL
  4. DL

Answer: 2. HDL

Question 57. Which of the following is a derived protein?

  1. Haemoglobin
  2. Albumin
  3. Globulin
  4. Peptone

Answer: 1. Haemoglobin

Question 58. The cell membrane is composed of

  1. Proteins and lipids
  2. Proteins and polysaccharides
  3. Proteins, lipids, and carbohydrates
  4. All of these

Answer: 1. Proteins and lipids

Question 59. Lipid is an

  1. Acidic compound
  2. Alcoholic compound
  3. Ester
  4. Aldehyde

Answer: 3. Ester

Question 60. The simple structural formula of lipids is

  1. C-ROOH
  2. R-CHO
  3. R-COOH
  4. R=CO

Answer: 3. R-COOH

Question 61. An essential component of lipids is—

  1. Nucleic acid
  2. Malic acid
  3. Fatty acid
  4. Amino acid

Answer: 3. Fatty acid

Question 62. The functional bond that helps to form a lipid molecule is—

  1. Ester bond
  2. Hydrogen bond
  3. Peptide bond
  4. Sulfide bond

Answer: 1. Ester bond

Question 63. The highest calorific value is seen in which of the following four nutrients?

  1. Protein
  2. Carbohydrate
  3. Fat
  4. Vitamin

Answer: 3. Fat

Chapter 2 Life Science Quiz Questions

Question 64. Wax is a type of—

  1. Carbohydrates
  2. Glycoproteins
  3. Lipids
  4. Lipoproteins

Answer: 2. Glycoproteins

Question 65. During hibernation, energy is supplied to the organism by—

  1. Carbohydrate
  2. Protein
  3. Vitamin
  4. Fat

Answer: 4. Fat

Question 66. DNA is a

  1. Single-stranded chain of nucleotides
  2. Double-stranded chain of polypeptides
  3. Double-stranded chain of nucleotides
  4. Double-stranded chain of amino acids

Answer: 3. Double-stranded chain of nucleotides

Question 67. In a DNA molecule, hydrogen bonding occurs between—

  1. Adenine and guanine
  2. Thymine and cytosine
  3. Adenine and cytosine
  4. Guanine and cytosine

Answer: 4. Guanine and cytosine

West Bengal Board Class 9 Life Science Book Solution

Question 68. The sugar present in DNA is—

  1. Triose
  2. Pentose
  3. Hexose
  4. Heptose

Answer: 2. Pentose

Question 69. Nitrogenous bases, present in both DNA and RNA, are—

  1. Adenine, guanine, cytosine
  2. Adenine, guanine, thymine
  3. Adenine, thymine, uracil
  4. Adenine, guanine, uracil

Answer: 1. Adenine, guanine, cytosine

Question 70. Which of the following carbohydrates is present in RNA?

  1. Ribulose
  2. Deoxyribose
  3. Ribose
  4. None of these

Answer: 3. Ribose

Chapter 2 Levels Of Organization Of Life Organic And Inorganic Molecules

Multiple Choice Questions

Question 1. Which of the following combinations of vitamins are fat soluble?

  1. Vit. A Vit. B and Vit. K
  2. D Vit. A Vit. B and Vit. C
  3. Vit. A Vit. D and Vit. E
  4. Vit. B, Vit. C and Vit. P

Answer: 3. Vit. A Vit. D and Vit. E

Question 2. Which combination includes all macroelements?

  1. Calcium, magnesium, and boron
  2. Sodium, potassium, and iodine
  3. Sodium, molybdenum, and iron
  4. Potassium, calcium, and phosphorus

Answer: 4. Potassium, calcium, and phosphorus

Question 3. A vitamin related to blood coagulation is

  1. Vit. A
  2. Vit. E
  3. Vit. D
  4. Vit. K

Answer: 4. Vit. K

Question 4.  Which combination of vitamins and minerals is related to the formation of bones and teeth?

  1. Vit. A and phosphorus
  2. Vit. D and calcium
  3. Vit. C and calcium
  4. Vit. D and sodium

Answer: 2. Vit. D and calcium

Question 5. To get vitamin K, you will have to eat

  1. Guava
  2. Lettuce
  3. Butter
  4. Tomato

Answer: 2. Lettuce

Question 6. Pellagra is caused due to the deficiency of

  1. Vit. B6
  2. Vit. B5
  3. Vit. B3
  4. Vit. B12

Answer: 2. Vit. B5

Question 7. Pernicious anemia occurs due to a deficiency of

  1. Vit. B6
  2. Vit. B5
  3. Vit. B3
  4. Vit. B12

Answer: 4. Vit. B12

Question 8. Chlorosis in plants can be seen in the deficiency of

  1. Calcium
  2. Magnesium
  3. Oxygen
  4. Sodium

Answer: 2. Magnesium

Question 9. Name the vitamin that helps in developing immunity against common cough and cold.

  1. Retinol
  2. Pantothenic acid
  3. Ascorbic acid
  4. Calciferol

Answer: 3. Ascorbic acid

Question 10. Which of the following food items should one take to prevent xerophthalmia?

  1. Papaya
  2. Pulses
  3. Carrot
  4. Beans

Answer: 3. Carrot

Question 11. Which vitamin can reduce the chance of fetal death?

  1. Vit. B12
  2. Vit. E
  3. Vit. K
  4. Vit. B6

Answer: 2. Vit. E

Question 12. Which combination of elements is widely used in making fertilizers?

  1. N, C, H
  2. N, P, K
  3. N, Fe, Mg
  4. Mn, K, C

Answer: 2. N, P, K

Question 13. A microelement helping in the fixation and assimilation of nitrogen

  1. Molybdenum
  2. Magnesium
  3. Manganese
  4. Potassium

Answer: 1. Molybdenum

Question 14. The disease caused by a deficiency of iodine is

  1. Night blindness
  2. Beriberi
  3. Goitre
  4. Anaemia

Answer: 3. Goitre

Question 15. The provitamin of vitamin A is

  1. Beta carotene
  2. Retinol
  3. Calciferol
  4. Pyrithiamine

Answer: 1. Beta carotene

Study Tips for Class 9 Organic and Inorganic Molecules MCQs

Question 16. The contraction of muscles is controlled by

  1. Magnesium
  2. Calcium
  3. Phosphorus
  4. Iron

Answer: 2. Calcium

Question 17. Which of the following vitamins is insoluble in fat?

  1. Vitamin A
  2. Vitamin C
  3. Vitamin D
  4. Vitamin K

Answer: 2. Vitamin C

Question 18. Which of the following vitamins is insoluble in water?

  1. Vitamin C
  2. Vitamin P
  3. Vitamin M
  4. Vitamin E

Answer: 4. Vitamin E

Question 19. A water-soluble vitamin is

  1. Vitamin A
  2. Vitamin C
  3. Vitamin D
  4. Vitamin E

Answer: 2. Vitamin C

Question 20. The biomolecule that prevents the action of vitamins is called

  1. Pseudo vitamin
  2. Antivitamin
  3. Provitamin
  4. All of these

Answer: 2. Antivitamin

Question 21. Which of the following is an antivitamin?

  1. Galactoflavin
  2. Riboflavin
  3. Thiamin
  4. Cyanocobalamin

Answer: 1. Galactoflavin

Question 22. Vitamin A is produced in the liver from

  1. Ergosterol
  2. Avidin
  3. Carotene
  4. Citral

Answer: 3. Carotene

Question 23. 95% of vitamin A, absorbed in the human body is stored in

  1. Kidney
  2. Lungs
  3. Liver
  4. Stomach

Answer: 3. Liver

Question 24. The disease caused due to deficiency of vitamin A is

  1. Sterility
  2. Osteomalacia
  3. Rickets
  4. Night blindness

Answer: 4. Night blindness

Question 25.  Xerophthalmia occurs due to a deficiency of vitamin

  1. C
  2. A
  3. E
  4. K

Answer: 2. A

Question 26. Osteomalacia is caused due to deficiency of

  1. Vitamin C
  2. Vitamin A
  3. Vitamin D
  4. Vitamin K

Answer: 3. Vitamin D

Question 27. Deficiency of which vitamin in children does result in rickets?

  1. Vit. D
  2. Vit. A
  3. Vit. C
  4. Vit. K

Answer: 1. Vit. D

Question 28. Tetany occurs due to a deficiency of

  1. Vitamin C
  2. Vitamin D
  3. Vitamin E
  4. Vitamin K

Answer: 2. Vitamin D

Question 29. The vitamin that is known as anti sterility factor is

  1. Calciferol
  2. Phylloquinone
  3. Tocopherol
  4. Retinol

Answer: 2. Tocopherol

Question 30. Which of the following vitamins is known as the ‘Antihaemorrhagic factor’?

  1. Vit. K
  2. Vit B5
  3. Vit. D
  4. Vit. C

Answer: 1. Vit B5

Question 31. Which vitamin does help in blood clotting?

  1. Vit. A
  2. Vit. D
  3. Vit. E
  4. Vit. K

Answer: 4. Vit. K

Question 32. Which vitamin does help in maintaining normal prothrombin levels in blood?

  1. Vit. K
  2. Vit. B
  3. Vit. B5
  4. Vit. C

Answer: 1. Vit. K

Question 33. Deficiency of which vitamin does result in pernicious anemia?

  1. Vit. B2
  2. Vit. B5
  3. Vit. B12
  4. Vit. B6

Answer: 3. Vit. B12

Question 34. PP factor is

  1. Vit. A
  2. Vit. B12
  3. Vit. D
  4. Vit. B3

Answer: 4. Vit. B3

Question 35. Megaloblastic anemia occurs deficiency of

  1. Pyridoxine
  2. Folic acid
  3. Niacin
  4. Biotin

Answer: 2. Folic acid

Question 36. Deficiency of which vitamin does cause beriberi?

  1. Vit. B1
  2. Vit B2
  3. Vit B5
  4. Vit. B12

Answer: 1. Vit. B1

Question 37. The chemical name of vitamin B1 is

  1. Niacin
  2. Thiamin
  3. Pyridoxine
  4. Riboflavin

Answer: 2. Thiamin

Question 38. The chemical name of vitamin C is

  1. Tocopherol
  2. Ascorbic acid
  3. Retinol
  4. Thiamine

Answer: 2. Ascorbic acid

Question 39. The disease that is caused due to deficiency of vitamin C is

  1. Rickets.
  2. Osteomalacia
  3. Scurvy
  4. Beriberi

Answer: 3. Scurvy

Question 40. Biotin was previously known as

  1. Vitamin G
  2. Vitamin H
  3. Vitamin M
  4. Vitamin K

Answer: 2. Vitamin H

Question 41. Which of the following sets of vitamins are antioxidants?

  1. B1,B6, B12
  2. A, E, C
  3. D, K, B2 
  4. B1, B5, B6

Answer: 2. A, E, C

Question 42. One macro-element for the human body is

  1. Zn
  2. Cu
  3. Ca
  4. Cr

Answer: 3. Ca

Question 43. Which one of the following is a microelement?

  1. N
  2. P
  3. K
  4. Mo

Answer:

4. Mo

Question 44. Which one is required for blood coagulation?

  1. P
  2. K
  3. Na
  4. Ca

Answer: 4. Ca

Question 45. The disease caused in animals due to deficiency of iodine is

  1. Night blindness
  2. Beriberi
  3. Goiter
  4. Anaemia.

Answer: 3. Goiter

Question 46. Helps in the synthesis of thyroxine

  1. Ca
  2. K
  3. P
  4. I

Answer: 4. 1

Question 47. Which mineral helps in hemoglobin?

  1. Calcium
  2. Potassium
  3. Magnesium
  4. Iron

Answer: 4. Iron

Question 48. Deficiency of which mineral element does result in anemia?

  1. Magnesium
  2. Iron
  3. Calcium
  4. Phosphorus

Answer: 2. Iron

Question 49. Which mineral does help in the transmission of nerve impulses and contraction of heart muscles?

  1. Sodium
  2. Iron
  3. Copper
  4. Iodine

Answer: 1. Sodium

 

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