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 for health fats fats and their test different nutrients in food

Which of the following has the highest calories per gram?

  1. Proteins

  2. Fats

  3. Sugar

  4. Glucose
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Calories are needed to provide energy so the body functions properly. The number of calories in a food depends on the amount of energy the food provides. The number of calories a person needs depends on age, height, weight, gender, and activity level. People who consume more calories than they burn off in normal daily activity or during exercise are more likely to be overweight.

The amount of energy one will get from carbohydrate, protein and fat is measured in calories per gram. Fats have the most energy and proteins have the same amount as carbohydrates, but their value as a source of energy is determined by more than the calories gained from one gram.
Fat: 1 gram = 9 calories 
Protein: 1 gram = 4 calories 
Carbohydrates: 1 gram = 4 calories

Therefore, the correct answer is option B.

Multiple choice biology food for health fats fats and their test different nutrients in food

Long term energy storage occurs in the form of

  1. Glucose

  2. Amino acids

  3. Glycogen

  4. Fat
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

While glycogen is used for short term energy storage in the liver and muscles, fat is the primary form for long term energy storage in the body due to its high energy density.

Multiple choice biology food for health fats fats and their test different nutrients in food

A gram of butter provides more energy that a gram of sugar because

  1. Butter is an animal product

  2. Butter has more carbon-hydrogen bonds

  3. Butter is more completely absorbed

  4. Butter contains more ATP
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Carbohydrates which includes  sugars and starches, contain 4 calories per gram, and are considered one of the main sources of energy for the human body. Fats on the other hand give 9 calories per gram,which is approximately 2.5 times more energy than carbohydrates. Moreover, fats contain more carbon-carbon and carbon-hydrogen bonds than carbohydrates or proteins and are therefore richer in energy. 

Therefore, the correct answer is option B.

Multiple choice biology food for health fats fats and their test different nutrients in food

A gram of butter provides more energy than a gram of sugar because

  1. Butter is digested slowly

  2. Butter has more carbon-hydrogen bonds

  3. Butter is more completely absorbed

  4. Butter contains more ATP
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A gram of butter provides more energy than a gram of sugar because butter has more carbon-hydrogen bonds.

The carbohydrates are the compounds which provide energy to living cells. They are compounds of carbon, hydrogen and oxygen with a ratio of two hydrogens for every oxygen atom. The carbohydrates we use as foods have their origin in the photosynthesis of plants. They take the form of sugars, starches, and cellulose.

Multiple choice biology food for health fats fats and their test different nutrients in food

A gram of butter provides more energy than a gram of sugar because

  1. Butter is an animal product.

  2. Butter has more carbon-hydrogen bonds.

  3. Butter is more completely absorbed.

  4. Butter contains more ATP.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fat contains 9 kcal per gram, whereas carbohydrates and protein only contain 4 kcal per gram. 

Triglycerides or fats are composed of one molecule of glycerol and joined via ester bonds with three molecules of fatty acids. Fatty acids are long chains of carbon and hydrogen usually between 14-24 carbons long. Due to the abundance of C and H, fatty acids are very hydrophobic and are not very soluble in water. 
Fatty acids come in two major types, saturated and unsaturated. Saturated means that they have no double bonds. Unsaturated means that it contains double bonds. Generally, saturated fats (butter) have a high melting point so that they are a solid at room temperature. Unsaturated fats have a lower melting point and are a liquid at room temperature. Margarine is made by hydrogenating (adding H) to unsaturated vegetable oils increasing the amount of saturation and thus, the melting point (so it will be a solid). 

Multiple choice properties of enzyme enzyme properties enzymes biomolecules: chemical constituents of living cells biology
Which of the following is an example of isozyme?
  1. $\alpha$-amylase

  2. Glucokinase

  3. Lactate dehydrogenase

  4. All of the above

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The multiple molecular forms of an enzyme occurring in the same organism and having a similar substrate activity are called isoenzymes or isozymes. They have similar properties but different molecular weights and locations. Over 100 enzymes are known to have isoenzymes. $\alpha$-amylase of wheat endosperm, has 16 isozymes, lactate dehydrogenase has 5 isozymes. Glucokinase is an isozyme of hexokinase.
So, the correct answer is 'All of the above'.
Multiple choice chemistry chemical kinetics kinetic study of some first order reactions rate of chemical reaction endothermic and exothermic reactions

Inversion of cane sugar in dilute acid is:

  1. bimolecular reaction

  2. pseudo-unimolecular reaction

  3. unimolecular reaction

  4. trimolecular reaction
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

${ C } _{ 12 }{ H } _{ 22 }{ O } _{ 11 }+{ H } _{ 2 }O\xrightarrow [  ]{ \quad { H }^{ + }\quad  } { C } _{ 6 }{ H } _{ 12 }{ O } _{ 6 }+{ C } _{ 6 }{ H } _{ 12 }{ O } _{ 6 }$
Rate $=k\left[ { C } _{ 12 }{ H } _{ 22 }{ O } _{ 11 } \right] \left[ { H } _{ 2 }O \right] $
When water is in excess, its concentration will be constant.
$\therefore $ Rate $={ k }^{ ' }\left[ { C } _{ 12 }{ H } _{ 22 }{ O } _{ 11 } \right] $
The reaction is, therefore, pseudo first order or pseudo unimolecular reaction.

Multiple choice chemistry chemical kinetics kinetic study of some first order reactions rate of chemical reaction endothermic and exothermic reactions

The inversion of cane sugar into glucose and fructose is:

  1. $I$ order
  2. $II$ order
  3. $III$ order

  4. zero order
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Inversion of cane sugar follow Ist order reaction while its molecularity is 2 and reaction is given by
$ \implies C _{12}H _{22}O _{11} +H _2O \rightarrow C _6 H _{12}O _6 + C _6H _{12}O _6$

Here the rate of reaction is dependent on only $C _{12}H _{22}O _{11}$.

Multiple choice biology endocrine glands different type of gland glands in humans coordination in human beings- chemical control

Diosgenin is

  1. Saccharide

  2. Steroid

  3. Amino acids

  4. Peptide
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Diosgenin, a plant steroid sapogenin. Diosgenin is the product of hydrolysis by acids, strong bases, or enzymes of saponins which are extracted from the tubers of Dioscorea wild yam. Diosgenin is used for the commercial synthesis of cortisone, pregnenolone, progesterone, and other steroid products. 

So, the correct answer is 'Steroid'.

Multiple choice evs farming brings prosperity agriculture and types of crops crop management management of crops in india

On storage, the sweetness of corn is lost due to conversion of soluble sugars into polysaccharide. If corn is immersed after harvest in boiling water and cooled, the sweetness remains because the.

  1. Polysaccharide is re-converted into soluble sugars

  2. Concentration of sugar increases due to heating

  3. Conversion of sugars to polysaccharide stops

  4. Enzymes responsible for the conversion are destroyed
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice chemistry properties of natural resources conservation of water and recycling properties of water structure and properties of water

Which of the following is soluble in water ?

  1. salt

  2. sugar

  3. oxygen

  4. all of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Salt and sugar are soluble in water and form solution with water. Oxygen is also water soluble because the aquatic animals are able to breathe because oxygen is present in the dissolved form. As temperature increases solubility decreases, that's why in Eutrophication there is high BOD.(Biological Oxygen Demand)

Multiple choice expression of gene inherited changes biology

Lac-operon is related with _______

  1. Lactose metabolism

  2. Starch metabolism

  3. Lipid metabolism

  4. Protein metabolism
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Lac-operon refers to the group of genes present in bacteria that are responsible for the metabolism of lactose. There are three genes called LacZ, LacY and LacA that code of beta-galactosidase, permease and transacetylase respectively. They have a common promoter, operator and a regulator gene.

Hence, the correct answer is 'Lactose metabolism'

Multiple choice botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

One of the most resistant biological material is

  1. Lignin

  2. Hemicellulose

  3. Lignocellulose

  4. Sporopollenin
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The exine of the pollen grains consist most resistant biological material known as sporopollenin. It is resistant to both microbial and chemical decomposition by which it preserves pollen grains during fossilaization.

So, the correct option is 'Sporopollenin'.

Multiple choice biology windows of knowledge human tongue organ of taste tongue : the organ of taste

Milk contains a sugar called

  1. Galactose

  2. Lactose

  3. Maltose

  4. Sucrose
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A. Galactose is a monosaccharide sugar as sweet as glucose. It is found in butter, butter milk, buttermilk, cheese, cream and gums.
B. Lactose is a disaccharide sugar composed of galactose and glucose. Lac in Latin means milk. It comprises about 2-8 % of milk by weight so, it is important constituent of milk. It is also called as milk sugar. Other sources are buttermilk, cheese and cream.
C. Maltose is a disaccharide sugar composed of two units of glucose. It is found in germinating seeds, also called as malt sugar. It is found in cereals, pizza, and bread products.
D. Sucrose is a disaccharide sugar composed of glucose and fructose. It is also called as table sugar. It is found in sugarcane.
So, the correct answer is 'Lactose'.
Multiple choice biology windows of knowledge human tongue organ of taste tongue : the organ of taste

Identify the taste receptor of sweet taste.

  1. ENaC

  2. T2Rs

  3. PCKD channel

  4. T1R2 + T1R3
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
  • The upper surface of the tongue has small projections called papillae, some of which bear taste buds.
  • About 50 -150 taste cells are found in a taste bud. These cells detect all 4 tastes i.e sweet, sour, salty and bitter
  • The taste buds for "sweet" are on the tip of the tongue and have sweet receptors such as T1R2 + T1R3. These receptors have the ability to sense sweet taste and send signals to the brain.
  • So, the correct answer is 'T1R2 + T1R3.'.