Tag: biomolecules

Questions Related to biomolecules

Select the correct option:

Read the given statements.
i. Fructose is the sweetest sugar.
ii. Glycine is the simplest amino acid.
iii. Lactose is a disaccharide composed of one molecule each of glucose and galactose.
iv. Cellulose is an unbranched chain of glucose molecules linked by $\beta$1, 4-glycosidic bond.
Which of the given statements are correct?

  1. (i) and (ii)

  2. (iii) and (iv)

  3. (i), (ii) and (iii)

  4. (i), (ii), (iii) and (iv)


Correct Option: D
Explanation:

Carbohydrate, on the basis of the number of molecules present, is divided into monosaccharides, disaccharide and polysaccharides. Fructose is also known as the fruit sugar and is a monosaccharide. It is a 6 carbon molecule. Glycine is the simplest amino acid as it contains hydrogen in the side chain. Lactose is a disaccharide which means it has two molecules of same or different monosaccharide units. Lactose is also known as the milk sugar. 

On hydrolysis, lactose produces glucose and galactose.
Cellulose is a polysaccharide and an important constituent of cell wall it is made up of Beta D glucose units linked by 1-4 glycosidic linkage.

So, the correct option is '(i), (ii), (iii) and (iv)'

Which of these is not a macromolecule?

  1. Cellulose

  2. DNA

  3. Glycogen

  4. None of the above


Correct Option: D
Explanation:

Macromolecules are the molecules made by the attachment of micro molecule. These are complex molecules. Cellulose, DNA, and glycogen are macromolecules as they are formed by linkage of simple monomers.

Cellulose is a polysaccharide. It is formed by the linkage of beta 1,4 linkage of a glucose unit. It is an important component of the cell wall of the plant.
DNA and RNA are the chain of polynucleotide which are joined by the phosphodiester bonds.
Glycogen is a polymer of glucose. It's the structure similar to amylopectin where two polymeric chains of glucose of alpha 1,4 glucose unit are linked by alpha 1,6 linkage.
So, the correct answer is option D.

Joining of repeating units to form a macromolecule is called

  1. Polymerisation

  2. Aggregation

  3. Polymorphism

  4. Condensation


Correct Option: A
Explanation:

Polymerization is the process by which the simpler unit known as monomers attaches with the help of chemical bond to form a long chain or branched structure. It helps to produce new chemicals. It is a process of joining repeating units to form a macromolecule is known as polymerization. For example, proteins are building blocks of the body. The proteins are made up of amino acids. The amino acids are linked together by peptide bonds to form a protein. 

Polysaccharides are formed by the repeating unit of monosaccharides. 
So, the correct answer is option A. 

Pick out the wrong statement.

  1. Amino acids are substituted methanes.

  2. Is a trihydroxy propane.

  3. Lysine is a neutral amino acid.

  4. Lecithin is a phospholipid.

  5. Adenosine is a nucleoside.


Correct Option: C
Explanation:

Amino acids are amphoteric compounds having a carboxylic group, amino group, hydrogen and a substituent group bonded to same carbon atom called the $\alpha$-carbon atom. The substituent group may be having one or more carboxylic groups or amino groups. In case the substituent group is having an extra amino group, the amino acid will be having more than one amino groups and will be positively charged at neutral pH and will be a basic amino acid like lysine and arginine.

Similarly if substituent group carries extra carboxylic group, the amino acid will carry negative charge at neutral pH and will be an acidic amino acid like aspartic acid and glutamic acid.
In case the substituent group does not carry extra carboxylic or amino groups the amino acid is neutral amino acid example glycine, alanine, valine.

Which of the following statement is incorrect? Choose answer: 

  1. The acid insoluble fraction, has only four types of organic compounds, proteins, polysaccharides nucleic acids and lipids

  2. Chemical compounds found in living organisms are of two types, acid soluble and acid insoluble

  3. The compounds which are found in the acid insoluble fraction are called micromolecules

  4. The acid soluble pool represents roughly the cytoplasmic composition


Correct Option: C
Explanation:
Biomolecules with molecular weights more than one thousand Dalton are called biomacromolecules. These are found in the acid-insoluble fraction. Lipids are not strictly macromolecules as their molecular weights do not exceed 800 Da but form a part of the acid insoluble pool. The molecules in the insoluble fraction with the exception of lipids are polymeric substances. Lipids are indeed small molecular weight compounds and are present not only as such but also arranged into structures like cell membrane and other membranes. So the acid insoluble fraction has only four types of organic compounds, proteins, polysaccharides nucleic acids and lipids but except for lipids none of them are micromolecules.

So the correct option is 'The compounds which are found in the acid insoluble fraction are called micromolecules'.

Enzyme, vitamins and hormones can be classified into a single category of biological chemicals, because all of these

  1. Decrease metabolism.

  2. Are conjugated proteins.

  3. Are exclusively synthesized in the body of a living organism as at present.

  4. Help in regulating metabolism.


Correct Option: D
Explanation:

Enzymes, vitamins and hormones are critical to the central role of these elements in the metabolism. Some enzymes in addition to the proteinaceous part require an additional organic molecule coenzyme. Most of the coenzymes are derived from vitamins. Hormones are chemically a diverse group. They may be amines or steroids or peptides. The hormones regulate body metabolism over a longer duration and slowly effect the developmental changes during the development of an organism. The main difference between the enzyme (coenzyme) and hormones is the time scale of their operation. Both are similar in their role in regulating body metabolism.

Match column I with column II and select the correct option from the given codes.

 Sr.No List I  Sr.No  List II 
A.   GLUT-4  1.  Intercellular ground substance
B.   Antibody  2.  Enzyme
C.  Collagen  3.  Hormone
D.  Trypsin  4.  Flights infectious agents
E.  Insulin  5.  Enables glucose transport in cells
  1. A-(i),B-(ii),C-(iii),D-(iv),E-(v)

  2. A-(v),B-(iv),C-(i),D-(ii),E-(iii)

  3. A-(v),B-(iv),C-(iii),D-(ii),E-(i)

  4. A-(ii),B-(i),C-(iv),D-(v),E-(iii)


Correct Option: B
Explanation:

Antibodies are the structures that help in maintaining the immunity of the body towards the antigens that are infectious agent whether be it bacteria or viruses.

GLUT 4 is a component which helps and enables the glucose transport. Collagen is a type of secondary protein structure that is the component of the muscles and various tissue which has high tensile strength. Insulin is a hormone which is peptide in nature and the controls the sugar levels in the blood. Trypsin is an enzyme of digestive system secreted in the pancreatic juices.

So, the correct option is 'A-(v),B-(iv),C-(i),D-(ii),E-(iii)'

Which of the following are isomers?
  1. 3PGA and 2PGA

  2. PGAL and DHAP

  3. Glucose and Fructose

  4. All of these


Correct Option: D
Explanation:

Isomers are molecules that have the same molecular formula but have a different arrangement of the atoms in space. That excludes any different arrangements which are simply due to the molecule rotating as a whole or rotating about particular bonds. For example, in respiration, 3PGA and 2PGA, PGAL and DHAP, Glucose and Fructose. 

Thus, the correct answers is 'All of these.'

Which biomolecule is correctly characteristed? 

  1. Lecithin phosphorylated glyceride found in cell membrane

  2. Palmitic acid unsaturated fatty acid with 18 carbon atoms

  3. Adenylic acid adenosine with glucose phosphate molecule

  4. Alanine amino acid contains an amino acid and an acidic group anywhere in the molecule.


Correct Option: A
Explanation:

Lecithin is a phosphorylated glyceride. It is a phospholipid with glycerol, fatty acids ,a phosphate group and choline. It is found in the cell membrane. Palmitic acid is a saturated fatty acid with 16 carbon atoms. Adenylic acid is also called as Adenosine monophosphate (AMP). It is an adenosine with a phosphate group and the ribose sugar. It is an ester of phosphoric acid and the adenosine. Alanine is a neutral amino acid. It contains one amino group and one carboxylic group.

Thus, the correct answer is option A.

Chemical composition of a cell's components approx. % dry weight

  1. Carbohydrate, protein, fat, and nucleic acid

  2. Protein, fats, nucleic acid and carbohydrate

  3. Protein, fats, carbohydrates and nucleic acid.

  4. Carbohydrate, fats, proteins and nucleic acid


Correct Option: B
Explanation:

The composition of the different organic compounds in the animal body in terms of dry weight is as protein-71%, lipid-12%, nucleic acid-7%,  carbohydrate-5% and inorganic and other materials-5%. These four classes of organic material are important and form the basis of organic constituents in the cell. All these macromolecules except lipids are formed by the process of polymerisation. Due to their large size and complex 3-dimensional shape, these organic biomolecules function as structural components, enzymes, energy sources,molecular messengers, nutrient stores and sources of genetic information. Carbohydrates are polyhyroxyaldehydes or polyhyroxyketones or substances that gives this on hydrolysis. They are classified as monosaccharides, oligosaccharides and polysaccharides. Pentoses and hexoses are the most important sugars. Complex polysaccharides are important components of inter-cellular ground substances. Lipids are major and essential components of biological membranes. They are important dietery components and forms major forms of energy, because of their high calorific value. Protein is a polymer of different amino acids linked together by peptide bonds. Proteins can be fibrous or globular. Structural proteins serve as building materials for cells and tissues. Functional proteins regulate metabolism. Nucleotides, the monomer units of nucleic acids serve many important functions in cells. They store the genetic information in them. They are also primary carriers of chemical energy in cells, structural components of many enzyme cofactors and cellular second messengers. Thus, the four macromolecules play a significant role in performing various cellular functions.