Tag: food and it's constituents

Questions Related to food and it's constituents

Which of the following statements is not correct regarding chitin?

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

  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

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Correct Option: A
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'.

The primary function of carbohydrates in cells are

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

  1. Signal transduction

  2. Storage of information and catalysis of substances

  3. Energy storage and cell identity

  4. Catalysis and transport of various substances

Show answer
Correct Option: C
Explanation:

Primary functions of carbohydrates in the cells are as follows as:

  • Provide energy to all cells of the body of an organism.
  • Store energy in the form carbohydrates.
  • Also, help in building the macromolecule, proteins and fats.
  • Also, help in the formation of receptor ( e.g. lecithin) present on the cell surface and help in cell identity.
  • So, the correct answer is 'Energy storage and cell identity'.

How much energy is utilised in the synthesis of one gram mole of glucose?

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

  1. $673$ kcal

  2. $686$ kcal

  3. $666$ kcal

  4. $696$ kcal.

Show answer
Correct Option: B
Explanation:

$686$ kcal energy is utilised in the synthesis of one gram mole of glucose. 

When $1$ mol of glucose means $180$ g of glucose reacts with oxygen under standard conditions, so $686$ kcal is released in the reaction.
Hence, the correct option is B.

Which of these is not an aldose sugar?

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

  1. Glucose

  2. Mannose

  3. Fructose

  4. Ribose

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Correct Option: C
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'.

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

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

  1. Starch to sugar

  2. Sucrose to fructose

  3. Amino acids to sugar

  4. Amino acids to protein

Show answer
Correct Option: A
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'.

The relationship between glucose and sucrose is

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

  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.

Show answer
Correct Option: C
Explanation:

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

A reagent added to a sample shows change of colour from green to yellow. It is due to presence of reducing sugar. The test is

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

  1. Elisa test for detecting AIDS

  2. Benedict's test for detecting glucosuria

  3. Fehling's test for detecting hyperglycemia

  4. Ninhydrin test for detecting glucosidic linkage

Show answer
Correct Option: B
Explanation:
Benedict's test can be used to test reducing sugar that is glucose in urine. Glucose in urine is called glucosuria and it turns yellow in colour when benedict's test applied it shows that glucose is present in urine.
So the correct answer is B.

Iodine test used to detect

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

  1. Protein

  2. Fat

  3. Carbohydrate

  4. Chitin

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Correct Option: C

Starch changes colour and turns blue-black in ............ solution.

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

  1. Salt

  2. Eosin

  3. Iodine

  4. Dilute HCl

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Correct Option: C
Explanation:

Iodine present in the aqueous Potassium iodide solution gets entangled in the starch and forms starch Iodide complex. Hence starch turns blue-black or purple-black in colour.

So, the correct answer is option C.

A leaf is boiled in alcohol before using iodine for a starch test in order to

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

  1. dissolve starch

  2. dissolve chlorophyll

  3. soften the leaf

  4. make it react with iodine

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Correct Option: A