Biochemistry

Protein Structure and Components

• Primary structure of proteins refers to the unique sequence of amino acids.
• Alpha helix structure features hydrogen bonding that stabilizes its shape.
• Disulfide bonds form between cysteine residues, contributing to protein stability.
• Hemoglobin functions as an oxygen carrier, comprising four polypeptide chains and heme groups.

Amino Acids and Their Properties

• Imidazole group and aromatic ring are found in histidine.
• Glycine is the only amino acid that is not optically active due to having two identical hydrogen atoms.
• Secondary structure of proteins is stabilized by hydrogen bonds between backbones of amino acids.
• Proline reacts with ninhydrin to yield a characteristic yellow color, as it has a unique cyclic structure.

Vitamin Synthesis and Function

• Sunlight is required to synthesize vitamin D, which is crucial for calcium metabolism.
• Vitamin K is essential for blood clotting.
• Sources of vitamin C include citrus fruits, strawberries, and green vegetables.
• Vitamin A is scientifically known as retinol and is found in foods like carrots and liver.

Hormones and Proteins

• Steroid hormones are lipid-soluble and regulate various physiological processes by binding to specific receptors.
• Cholesterol serves as the building block for steroid hormones.
• Non-essential amino acids can be synthesized by the body, while essential amino acids must be obtained through the diet.

Protein Classification

• Ketogenic amino acids, such as leucine and lysine, can be converted into ketone bodies.
• Simple proteins lack complex structures and are made up of only amino acids.
• Partially incomplete proteins do not provide all essential amino acids in sufficient amounts.

Chemistry of Amino Acids

• Zwitter ions are dipolar ions that have both positive and negative charges but are overall electrically neutral.
• Isoelectric pH is the point at which an amino acid has no net charge, influencing solubility and migration in electric fields.

Carbohydrates and Fatty Acids

• Examples of homopolysaccharides include starch and cellulose, made up of repeating units of the same monosaccharide.
• Glucose is a keto sugar, while fructose serves as an example of a hexose sugar.
• Fatty acids are long hydrocarbon chains with a carboxylic acid group, vital for lipid formation.
• Monosaccharides are the simplest form of carbohydrates, consisting of single sugar units.