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Biomolecules

Q: Match the following.A. Homeostasis 1) InsulinB. Emergency hormone 2) Structure of insulinC. Metabolism 3) AdrenalineD. Peptide hormones 4) ThyroxineE. Pancreatic islets 5) Maintenance of constant internal environmentF. Sanger 6) Affect the properties of Plasma membrane

Homeostasis is the maintenance of constant internal environment.Adrenaline is an emergency hormone. It increases pulse rate, blood pressure during emergency and stimulates the breaking of liver glycogen into blood glucose.Thyroxine is useful in metabolism. Insulin is secreted from thyroid gland. It regulates general growth and development and controls carbohydrate, lipid and protein metabolism.Peptide hormones such as insulin, affect the properties of plasma membrane.Insulin is secreted in pancreatic islets. It controls carbohydrate metabolism and maintains glucose level in the blood.Sanger represents the structure of insulin.

Q: Match the following:Name of the sugar Hydrolysis productsA) Sucrose i) Glucose \$+\$ Fructose \$+\$ GalactoseB) Lactoseii) Glucose \$+\$ FructoseC) Maltoseiii) Glucose \$+\$ GalactoseD) Raffinoseiv) Glucose \$+\$ Glucose

(A) Sucrose is made up of glucose and fructose molecules. When sucrose is consumed, the enzyme separates sucrose into its individual sugar units of glucose and fructose.(B) Lactose is a disaccharide, a type of sugar composed of two simple sugars, glucose and galactose. (C) Maltose is made up of two molecules of glucose.(D) Raffinose is a trisaccharide composed of galactose, glucose, and fructose.\$\therefore\$ Option (C) is correct.

Q: The ratio of the number of ketonic groups in cytosine, thymine and uracil is:

As evident from the image, the ratio of the number of ketonic groups in cytosine, thymine and uracil is \$1:2:2\$Hence, option A is correct.

Q: Which of the following carbohydrates is not a monosaccharide?

Sugars are categorized into monosaccharides or disaccharides.Monosaccharides are made up of one single unit of sugar and thus cannot be hydrolyzed further into simpler compounds. Examples:- galactose, glucose, and fructose.These are the building blocks of other carbohydrates like disaccharides and polysaccharides.Disaccharides are made up of two monosaccharides linked by glycosidic linkage and will be again broken back down into the latter during digestion Sucrose is the scientific name for table sugar and is a disaccharide.So the correct answer is option D.

Q: Which of the following statement(s) is/are correct?I. Starch is almost insoluble in cold water but relatively more soluble in boiling water.II. Starch solution gives blue colour with \$I_2\$ solution in cold.III. Starch is a reducing sugar.IV. Starch forms osazone.

I. Starch is a polysaccharide. It is almost insoluble in cold water but relatively more soluble in boiling water.Thus, statement I is correct.II. Starch solution gives blue colour with \$I_2\$ solution in cold. Amylose, a component of starch, gives this blue colour with iodine.Thus statement II is correct.III. Starch is non-reducing sugar as the aldehyde group is not free.Hence, statement III is incorrect.IV. Starch cannot form osazone as the aldehyde group is not free.Hence, statement IV is incorrect.

Q: A tetrapeptide has \$-COOH\$ group on alanine. This produces glycine (Gly), valine (Val), phenyl alanine (Phe) and alanine (Ala), on complete hydrolysis. For this tetrapeptide, the number of possible sequences (primary structures) with \$NH_{2}\$ group attached to a chiral centre is:

Since \$-COOH\$ group is attached to alanine, one terminal of the tetrapeptide contains alanine. Thus, its position is fixed.Glycine is achiral whereas valine and phenylalanine are chiral. Thus, \$-NH_2\$ group is attached to either valine or phenylalanine.Thus following are the four possible combinations of the tetrapeptide.\$H_2N-Val-Gly-Phe-Ala-COOH\$\$H_2N-Val-Phe-Gly-Ala-COOH\$\$H_2N-Phe-Gly-Val-Ala-COOH\$\$H_2N-Phe-Val-Gly-Ala-COOH\$Therefore, the correct option is A.

Q: Reducing sugar can reduce:

A reducing sugar is any sugar that either has an aldehyde group or is capable of forming one in the solution, through isomerism.The aldehyde functional group allows the sugar to act as a reducing agent, or example, in the Tollens' test or Benedict's reagent. Fehling's solution is used to test for the presence of a reducing sugar. The reducing sugar reduces copper(II) ions in these test solutions to copper(I), which then forms a brick red copper(I) oxide precipitate. An example is given in the attached image.Option D is correct.

Q: The sugar and purine rings are connected at which carbons?

The sugar and purine rings are connected at 1,6 position of carbon.

Q: The reagent which may be used to distinguish between cane sugar and glucose solutions is:

STATEMENT-1 is False, STATEMENT-2 is True

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A tetrapeptide has $- C O O H$ group on alanine. This produces glycine (Gly), valine (Val), phenyl alanine (Phe) and alanine (Ala), on complete hydrolysis. For this tetrapeptide, the number of possible sequences (primary structures) with $N H_{2}$ group attached to a chiral centre is:

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Reducing sugar can reduce:

Aldehydes to alcohols

Ferric salts to ferrous salts

Chlorates to chlorides

Fehling solution to cuprous oxide

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The sugar and purine rings are connected at which carbons?

1, 3

1, 6

1, 9

5, 9

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The reagent which may be used to distinguish between cane sugar and glucose solutions is:

I_{2}

solution

Baeyer's reagent

Both

A

and

B

Fehling's solution

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A) Sucrose	i) Glucose $+$ Fructose $+$ Galactose
B) Lactose	ii) Glucose $+$ Fructose
C) Maltose	iii) Glucose $+$ Galactose
D) Raffinose	iv) Glucose $+$ Glucose

Biomolecules

Chemistry 3953 Views

Match the following. A. Homeostasis 1) Insulin B. Emergency hormone 2) Structure of insulin C. Metabolism 3) Adrenaline D. Peptide hormones 4) Thyroxine E. Pancreatic islets 5) Maintenance of constant internal environment F. Sanger 6) Affect the properties of Plasma membrane

Match the following: Name of the sugar Hydrolysis products A) Sucrose i) Glucose + Fructose + GalactoseB) Lactoseii) Glucose + FructoseC) Maltoseiii) Glucose + GalactoseD) Raffinoseiv) Glucose + Glucose

The ratio of the number of ketonic groups in cytosine, thymine and uracil is:

Which of the following carbohydrates is not a monosaccharide?

Which of the following statement(s) is/are correct? I. Starch is almost insoluble in cold water but relatively more soluble in boiling water. II. Starch solution gives blue colour with I2​ solution in cold. III. Starch is a reducing sugar. IV. Starch forms osazone.

STATEMENT-1 : Sucrose is reducing sugar where as maltose is non reducing sugar.STATEMENT-2 : In disaccharides, the reducing property depends upon the position of linkages between the two monosaccharide units.

A tetrapeptide has −COOH group on alanine. This produces glycine (Gly), valine (Val), phenyl alanine (Phe) and alanine (Ala), on complete hydrolysis. For this tetrapeptide, the number of possible sequences (primary structures) with NH2​ group attached to a chiral centre is:

Reducing sugar can reduce:

The sugar and purine rings are connected at which carbons?

The reagent which may be used to distinguish between cane sugar and glucose solutions is:

Chemistry
3953 Views

Match the following.
A. Homeostasis 1) Insulin
B. Emergency hormone 2) Structure of insulin
C. Metabolism 3) Adrenaline
D. Peptide hormones 4) Thyroxine
E. Pancreatic islets 5) Maintenance of constant internal environment
F. Sanger 6) Affect the properties of Plasma membrane

Match the following:

Name of the sugar Hydrolysis products

A) Sucrose i) Glucose $+$ Fructose $+$ Galactose
B) Lactose ii) Glucose $+$ Fructose
C) Maltose iii) Glucose $+$ Galactose
D) Raffinose iv) Glucose $+$ Glucose

Which of the following statement(s) is/are correct?
I. Starch is almost insoluble in cold water but relatively more soluble in boiling water.
II. Starch solution gives blue colour with $I_{2}$ solution in cold.
III. Starch is a reducing sugar.
IV. Starch forms osazone.

STATEMENT-1 : Sucrose is reducing sugar where as maltose is non reducing sugar.
STATEMENT-2 : In disaccharides, the reducing property depends upon the position of linkages between the two monosaccharide units.

A tetrapeptide has $- C O O H$ group on alanine. This produces glycine (Gly), valine (Val), phenyl alanine (Phe) and alanine (Ala), on complete hydrolysis. For this tetrapeptide, the number of possible sequences (primary structures) with $N H_{2}$ group attached to a chiral centre is: