Biology · Chemistry

Carbohydrates and Biomolecules

1,073 Questions

Carbohydrates and biomolecules questions test your understanding of sugars, monosaccharides, and metabolic substrates. The topic covers food transportation in plants and the biochemical properties of sweeteners. Practicing these questions builds a strong foundation for exam preparation.

Disaccharides and monosaccharidesArtificial sweetenersGlycogen storagePlant food transportGlycoprotein hormones

Carbohydrates and Biomolecules Questions

Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

Which one of the following is a non - reducing carbohydrate?

  1. $\displaystyle Maltose$
  2. $\displaystyle Sucrose$
  3. $\displaystyle Lactose$
  4. $\displaystyle Ribose$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A non-reducing sugar is a carbohydrate that is not oxidized by a weak oxidizing agent (an oxidizing agent that oxidizes aldehydes but not alcohols, such as the Tollen's reagent) in basic aqueous solution. The characteristic property of non-reducing sugars is that, in basic aqueous medium, they do not generate any compounds containing an aldehyde group. Example : sucrose, which contains neither a hemiacetal group nor a hemiketal group and, therefore, is stable in water.

Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

Three important polysaccharides made up of glucose monomers are-

  1. Sucrose, Lactose, Maltose

  2. Chitin, Glycogen, Starch

  3. Starch, Glycogen, Cellulose

  4. RNA, DNA, Starch
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

  • Polysaccharides are carbohydrates whose molecules are made up of sugar molecules bonded together. They are composed of long-chain of monosaccharides. They range in structure from linear to highly branched form. They are made up of sugar mainly including glucose, fructose, etc.
So, the correct option is 'Sucrose, Lactose, Maltose'.

Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

A polysaccharide is made up of which kind of monomers?

  1. Simple sugars

  2. Amino acids

  3. Nucleotides

  4. Fatty acids and glycerol
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Simple sugars are the monomers for the polysaccharides or carbohydrates. Simple sugars include glucose, fructose, ribose, xylose, etc.

Amino acids are the monomers for the polypeptide chains or proteins.
Nucleotides are the monomers of the nucleic acids i.e. DNA and RNA. Each nucleotide contains mainly three parts, namely sugar molecule, a nitrogenous base and a phosphate molecule.
Three molecules of fatty acids and one molecule of glycerol together form the fats and oils.
So, the correct option is 'Simple sugars'.

Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

Select the correct option:

How many carbon atoms are generally used in composition of monosaccharides?

  1. 3 to 7

  2. 1 to 5

  3. 5 to 10

  4. 5 to 15
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Carbohydrates are also called saccharides because their basic components are sugars. Monosaccharides are those sugars or simple carbohydrate monomers which cannot be hydrolysed further into smaller components. They have a general formula of $C _nH _{2n}O _n$. Depending upon the number of carbon atoms, monosaccharides are of five types : trioses (having 3 carbon atoms, glyceraldehyde), tetroses (having four carbon atoms, e.g., erythrose), pentoses (having five carbon atoms, e.g, ribose), hexoses (having six carbon atoms, e.g.; glucose), heptoses (having seven carbon atoms, e.g., sedoheptulose).

So, the correct answer is '3 to 7'.

Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

Carbohydrates, the most abundant biomolecules on earth, are produced by

  1. Some bacteria, algae and green plant cells

  2. All bacteria, fungi and algae

  3. Fungi, algae and green plants cells

  4. Viruses, fungi and bacteria
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Photosynthesis is a process of generating the food for green plants and other organisms. It involves the conversion of light energy, normally from the Sun, into chemical energy in form of ATP. This chemical energy is stored in carbohydrate molecules, such as sugars, which are synthesized from carbon dioxide and water. In most cases, oxygen is also released as a waste product. Most plants, most algae and cyanobacteria perform photosynthesis. Such organisms are called photoautotrophs. Thus, option A is correct. Carbohydrates are not produced by fungi and viruses. Thus, other options are wrong.

Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

Which of the following statements is not correct regarding chitin?

  1. It is a storage polysaccharide

  2. It is a homopolysaccharide

  3. It is constituent of arthropod exoskeleton and fungal cell wall
  4. It contain $\beta 1-4$ glycosidic bond
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chhtitn is the main ingredient in the exoskeletons of arthropods and crustaceans and is also in the cell walls of fungi. That means everything from beetles, spiders, and butterflies to lobsters, crabs, and shrimps have some chitin in their protective armors.

So, the correct option is 'It is storage polysaccharide'.

Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

Which of these is not an aldose sugar?

  1. Glucose

  2. Mannose

  3. Fructose

  4. Ribose
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Aldose and ketose are two different types of sugars, which are named on the basis of presence of functional group, aldehyde or ketone. The sugars which contain aldehyde(-CHO) as a functional group are named as aldoses, while sugars which contain Ketone(-CO-) as a functional group are called as ketoses. In the given question glucose, ribose, and mannose, contains aldehyde as a function group and therefore are examples of aldoses. However, fructose contains a Ketone group and therefore it is a ketose and not aldose.
So, the correct answer is 'Fructose'.
Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

Raw banana has bitter taste, while ripe banana has sweet taste. It happens because of the conversion of

  1. Starch to sugar

  2. Sucrose to fructose

  3. Amino acids to sugar

  4. Amino acids to protein
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Raw banana has a bitter taste due to the presence of starch. When the banana ripens, the starch is converted to sugar in the form of glucose. The sugar is responsible for providing a sweet taste. So, the conversion is starch to sugar. 

Thus, the correct answer is 'starch to sugar'.

Multiple choice biology food and it's constituents energy giving food carbohydrate and its test biological molecules

The relationship between glucose and sucrose is

  1. Glucose is sucrose, with an extra -OH group at the $3'$ position.

  2. Sucrose is compared of two glucose molecules joined by a glycoside bond.

  3. A glucose molecule, joined to a fructose molecule makes a molecule of sucrose.

  4. Glucose is compared of two sucrose molecules, joined by a glycoside bond.

  5. Glucose is compared of a fructose and a sucrose molecule, joined by a glycoside bond.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Glucose and fructose are simple sugars known as monosaccharides. Sucrose is a disaccharide. Sucrose is made up of 2 simple sugars - glucose + fructose. 

Multiple choice biology economic importance of bacteria and fungi common diseases in humans epidemics transmission of diseases

Consider the following substances.
a. Cellulose
b. Glucan
c. Lignin
Which of the statements is/are found as a component/components of fungal cell wall?

  1. $1$ and $2$ only
  2. $2$ and $3$ only
  3. $3$ only
  4. $1, 2$ and $3$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Fungal cell walls are primarily composed of chitin and glucans. Cellulose is typically found in plant cell walls, and lignin is a structural polymer in vascular plants.