biomolecules ncert

What is the primary function of biomolecules in living systems?

Biomolecules grow, sustain, and reproduce living systems.

What are carbohydrates primarily produced by?

Plants.

What are the three main groups of carbohydrates based on hydrolysis behavior?

Monosaccharides, Oligosaccharides, Polysaccharides.

What is a monosaccharide?

A carbohydrate that cannot be hydrolysed further to yield simpler sugars.

What are disaccharides?

Carbohydrates that yield two to ten monosaccharide units on hydrolysis.

What is the chemical formula that defines carbohydrates?

Cx(H2O)y.

What are reducing sugars?

Carbohydrates which can reduce Fehling's or Tollens' reagents.

What defines the primary structure of a protein?

The specific sequence of amino acids linked together.

What occurs during denaturation of proteins?

Loss of biological activity due to disruption of secondary and tertiary structures.

What are the two types of nucleic acids?

Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).

What is the role of enzymes in biochemical reactions?

To act as biocatalysts that speed up reactions by lowering activation energy.

What are vitamins?

Organic compounds required in small amounts for specific biological functions.

What are the two classifications of vitamins based on solubility?

Fat soluble (A, D, E, K) and Water soluble (B group and C).

What is the unit formed by the attachment of a base to the sugar molecule in nucleic acids called?

Nucleoside.

How are nucleotides linked together in nucleic acids?

By phosphodiester linkage.

What is the main structural difference between DNA and RNA?

DNA is double-stranded while RNA is single-stranded.

What are the three major types of RNA?

Messenger RNA (mRNA), Ribosomal RNA (rRNA), Transfer RNA (tRNA).

What is glycosidic linkage?

A bond between two monosaccharides formed through the loss of a water molecule.

What are essential amino acids?

Amino acids that cannot be synthesized by the body and must be obtained through diet.

What does the presence of a primary alcoholic group in glucose indicate?

It confirms the presence of an aldehydic group.

What type of protein structure involves multiple polypeptide chains?

Quaternary structure.

What is the cyclic form of glucose known as?

Pyranose structure.

Which vitamin is essential for blood clotting?

Vitamin K.

What is an anomer?

Isomers of a monosaccharide that differ in configuration at the anomeric carbon.

What is the result of hydrolyzing sucrose?

Glucose and fructose.

What is the major storage polysaccharide in animals?

Glycogen.

What is the primary function of lipids in living organisms?

Energy storage, structural components of cell membranes, and signaling molecules.

What are the main types of lipids?

Triglycerides, phospholipids, and sterols.

What is the structure of a triglyceride?

Glycerol molecule attached to three fatty acid chains.

What is a saturated fatty acid?

Fatty acids that have no double bonds between carbon atoms.

What is an unsaturated fatty acid?

Fatty acids that contain one or more double bonds between carbon atoms.

What is the role of phospholipids in cells?

They form the bilayer of cell membranes.

What are essential fatty acids?

Fatty acids that must be obtained through diet because the body cannot synthesize them.

What is the function of cholesterol in the body?

Cholesterol serves as a precursor for steroid hormones and is a component of cell membranes.

What are the sources of omega-3 fatty acids?

Fish oils, flaxseeds, and walnuts.

What is a peptide bond?

The bond that connects two amino acids together in a protein.

What are cofactors in enzymatic reactions?

Non-protein molecules that assist enzymes in catalyzing reactions.

What is the primary function of proteins in living organisms?

Proteins serve as structural components, enzymes, hormones, and play roles in transport and immune response.

What is a key characteristic of enzymes?

Enzymes are specific to their substrates and often work optimally at certain temperatures and pH levels.

What is the basic unit of a lipid?

The basic unit of a lipid is a fatty acid.

What defines the tertiary structure of a protein?

The overall three-dimensional shape formed by the folding of a polypeptide chain.

What are the building blocks of nucleic acids?

Nucleotides.

What role do antioxidants play in the body?

Antioxidants protect cells from damage caused by free radicals.

What is the importance of water in biological systems?

Water is essential for life, acting as a solvent, temperature buffer, and participant in biochemical reactions.

What is the process of transcription?

Transcription is the process of copying a segment of DNA into RNA.

What is the function of ribosomal RNA (rRNA)?

rRNA is a key component of ribosomes, aiding in protein synthesis.

What is the significance of the hydrophobic interaction in proteins?

Hydrophobic interactions help stabilize the protein structure by causing nonpolar side chains to be buried inside the molecule.