biology MCQs - 9th class Chapter 06 Mcqs

1

Which of the following are also known as 'Saccharides'?

A

Proteins

B

Lipids

C

Carbohydrates

D

Nucleic Acids

2

What percentage of the dry mass of protoplasm is made up of biomolecules?

A

7%

B

15%

C

50%

D

93%

3

Which of the following is the most abundant biomolecule in the dry mass of protoplasm?

A

Carbohydrates

B

Lipids

C

Proteins

D

Nucleic acids

4

The type of metabolism where complex molecules are broken down into simple ones is called?

A

Anabolism

B

Catabolism

C

Photosynthesis

D

Respiration

5

Which process uses energy to combine simpler substances into complex ones?

A

Catabolism

B

Anabolism

C

Digestion

D

Excretion

6

Monosaccharides are made of how many sugar molecules?

A

One

B

Two

C

Three

D

Many

7

Which of the following is a property of monosaccharides?

A

Insoluble in water

B

Tasteless

C

Sweet taste

D

Less soluble in water

8

Ribose and deoxyribose are examples of which type of monosaccharide?

A

Trioses

B

Tetroses

C

Pentoses

D

Hexoses

9

Glucose, fructose, and galactose are examples of which type of sugar?

A

Pentoses

B

Hexoses

C

Disaccharides

D

Polysaccharides

10

Sucrose is a disaccharide made of which two monosaccharides?

A

Glucose and Galactose

B

Glucose and Fructose

C

Two Glucose units

D

Glucose and Ribose

11

Which disaccharide is made of two glucose molecules?

A

Sucrose

B

Lactose

C

Maltose

D

Fructose

12

Which of the following is a property of polysaccharides?

A

Soluble in water

B

Sweet taste

C

Tasteless

D

Made of two sugar units

13

Which polysaccharide is known as animal starch and is stored in the liver and muscles?

A

Starch

B

Cellulose

C

Chitin

D

Glycogen

14

The cell wall of fungi is made of which modified form of cellulose?

A

Starch

B

Glycogen

C

Chitin

D

Keratin

15

Lactose, a disaccharide, is commonly found in which source?

A

Fruits

B

Cereals

C

Sugar cane

D

Milk and dairy products

16

Which carbohydrates are essential parts of nucleic acids like RNA and DNA?

A

Hexoses

B

Pentoses

C

Disaccharides

D

Polysaccharides

17

The most abundant biomolecules in a cell are?

A

Carbohydrates

B

Lipids

C

Proteins

D

Nucleic Acids

18

How many different types of amino acids participate in the formation of proteins?

A

11

B

20

C

170

D

574

19

The protein insulin is made up of how many amino acids?

A

20

B

51

C

170

D

574

20

Which part of an amino acid makes it different from other amino acids?

A

Amino group

B

Carboxyl group

C

Hydrogen group

D

Side group (R)

21

In the amino acid alanine, what is the side group (R)?

A

H

B

CH3

C

COOH

D

NH2

22

Which of these proteins is responsible for making cartilage, hair, and nails?

A

Haemoglobin

B

Actin

C

Collagen and Keratin

D

Antibodies

23

Which protein transports oxygen in the blood?

A

Actin

B

Myosin

C

Haemoglobin

D

Fibrin

24

The proteins responsible for muscular contractions are?

A

Collagen and Keratin

B

Actin and myosin

C

Antibodies

D

Hormones

25

Which protein is involved in blood clotting?

A

Haemoglobin

B

Fibrin

C

Insulin

D

Keratin

26

Lipids are insoluble in water but soluble in?

A

Acids

B

Bases

C

Organic solvents

D

Salts

27

Lipids are composed of which two types of molecules?

A

Amino acids and glucose

B

Glycerol and fatty acids

C

Nucleotides and sugar

D

Monosaccharides and water

28

How many carbon atoms does a glycerol molecule have?

A

1

B

2

C

3

D

4

29

Fatty acids that have the maximum number of hydrogen atoms and no double bonds are called?

A

Unsaturated

B

Saturated

C

Polysaturated

D

Monosaturated

30

At room temperature, saturated fatty acids are typically?

A

Liquid

B

Gas

C

Solid

D

Plasma

31

Oils, which contain unsaturated fatty acids, are typically what at room temperature?

A

Solid

B

Liquid

C

Gas

D

Semi-solid

32

A phospholipid molecule consists of one glycerol, a phosphate group, and how many fatty acids?

A

One

B

Two

C

Three

D

Four

33

Which biomolecule is the most energy-rich?

A

Carbohydrates

B

Proteins

C

Lipids

D

Nucleic Acids

34

Steroid hormones are derived from which lipid?

A

Glycerol

B

Fatty acid

C

Cholesterol

D

Phospholipid

35

Nucleic acids are composed of units called?

A

Amino acids

B

Monosaccharides

C

Nucleotides

D

Fatty acids

36

What are the three components of a nucleotide?

A

Sugar, phosphate, amino group

B

Sugar, phosphate, nitrogenous base

C

Glycerol, fatty acid, phosphate

D

Sugar, carboxyl group, base

37

Which sugar is found in the nucleotides of DNA?

A

Ribose

B

Deoxyribose

C

Glucose

D

Fructose

38

Who proposed the double helix model of DNA in 1953?

A

Darwin and Lamarck

B

Watson and Crick

C

Schleiden and Schwann

D

Hooke and Leeuwenhoek

39

In the DNA double helix, adenine always pairs with which base?

A

Guanine

B

Cytosine

C

Thymine

D

Uracil

40

How many hydrogen bonds are formed between cytosine and guanine in a DNA molecule?

A

One

B

Two

C

Three

D

Four

41

A segment of DNA that determines the synthesis of a protein is called a?

A

Gene

B

Chromosome

C

Nucleotide

D

Codon

42

RNA is typically a single-stranded molecule composed of what?

A

Deoxyribonucleotides

B

Ribonucleotides

C

Amino acids

D

Fatty acids

43

Which nitrogenous base is found in RNA but not in DNA?

A

Adenine

B

Thymine

C

Guanine

D

Uracil

44

Which type of RNA carries genetic information from DNA to the ribosomes?

A

Messenger RNA (mRNA)

B

Transfer RNA (tRNA)

C

Ribosomal RNA (rRNA)

D

Small nuclear RNA (snRNA)

45

Which type of RNA transfers specific amino acids to the ribosomes?

A

Messenger RNA (mRNA)

B

Transfer RNA (tRNA)

C

Ribosomal RNA (rRNA)

D

Micro RNA (miRNA)

46

The process of making an mRNA copy from a DNA sequence is called?

A

Translation

B

Replication

C

Transcription

D

Duplication

47

The process where a ribosome reads the mRNA sequence to build a protein is called?

A

Transcription

B

Translation

C

Replication

D

Synthesis

48

What is the ratio of hydrogen to oxygen atoms in carbohydrates?

A

1:1

B

2:1

C

1:2

D

3:1

49

Which of the following is NOT a location where DNA is found in a eukaryotic cell?

A

Nucleus

B

Mitochondria

C

Ribosomes

D

Chloroplasts