Biomolecules Test - 15

B. Both the assertion and reason are true but the reason is not a correct explanation of the assertion.

The function of enzymes in the living system is to catalysed biochemical reactions without involving in the reaction. 

Linear chains of amino acids fold into stable geometries giving rise to secondary structures of proteins. $$\alpha$$-helix and $$\beta$$-sheets the most important secondary structures in proteins. Pauling and Corey discovered these two common elements of secondary structure (present in over 60% of known proteins), before the first crystal structure of a protein was determined. For this and other work in chemical bonding, Linus Pauling received the Nobel Prize in Chemistry in 1954.

• Proteins are biological macromolecules made up of amino acids. Amino acids are made up of carbon, hydrogen, oxygen, and nitrogen. 
• Nitrogen is present as an amino group attached to $$\alpha$$-carbon atom in amino acids.
• There is sulphur in the side chains of few amino acids like methionine and cysteine.

Proteins are macromolecules, i.e., bio-polymers made up of multiple units of amino acids. All biological proteins are synthesized from the different sequence of the same 20 amino acids. Because in proteins 20 different amino acids are used up hence, at each position of proteins there are 20 different possibilities. This gives rise to a combinatorial selection responsible for so many different types of proteins.

Enzymes are large biological molecules responsible for the thousands of metabolic processes that sustain life. They are highly selective catalysts, greatly accelerating both the rate and specificity of metabolic reactions, from the digestion of food to the synthesis of DNA. Most enzymes are proteins.

• The cytoplasm has two main components, such as cytosol, cell organelles, and cytoplasmic inclusions. 
• The cytosol is a fluid or jelly-like substance and is present within the cell membrane.
• Cell organelles are the small structures that help the cell in performing basic functions. 
• Cytoplasmic inclusions are tiny particles that are suspended in the cytoplasm.
• Since the cytoplasm has cytosol, a fluid-like and clear substance, it consists of 80 percent of water and because of this, cytoplasm acts as a medium for several cellular metabolic activities. 
• There are remaining components such as proteins, fats, and minerals, which constitute up to 25  percent together.

Enzymes are proteins. Enzymes are in general globular proteins.

Proteins are body building molecules and provide the structural framework for cells. They are biopolymers of amino acids. They are the largest physical and  chemical components of a cell. No other biomolecule possesses such immense structural and physiological diversity as proteins.