Cell Biomolecules Functions & Detection

Chemicals in living organisms that are essential for life processes like growth, reproduction, and sustenance.

Major components of cells, often more than 50% of the dry mass, performing tasks like accelerating reactions and cell communication.

Enzymes accelerate chemical reactions, transport substances, and support cell communication.

Sequence of amino acids linked in a protein determined by genes.

Coils and folds in polypeptide chains due to hydrogen bonds.

Proteins on cell surfaces that receive signals from outside the cell.

Proteins located within the cell which receives signaling molecules.

Adding a phosphate group to a molecule (often a protein), changing its activity.

The 3D shape of a single polypeptide chain, formed by interactions between its side chains (R groups).

The arrangement of multiple polypeptide chains (subunits) in a protein, forming a complex structure.

Strong covalent bonds that can stabilize the tertiary and quaternary structures of proteins.

A test that detects the presence of proteins by reacting with peptide bonds.

Used to detect α-amino acids in proteins and peptides.

Detects the presence of aromatic amino acids, like phenylalanine, tyrosine, and tryptophan, in proteins.

A fibrous protein with a unique structure of three polypeptide chains intertwined like a rope.

A globular protein responsible for transporting oxygen in red blood cells.

A general test for the presence of carbohydrates. It involves reacting the sample with Molisch reagent (alpha-naphthol in acidic medium) and concentrated sulfuric acid, which forms a purple ring at the interface if carbohydrates are present.

A test specifically for reducing sugars (like glucose, fructose, and lactose). It uses Benedict's reagent, which contains copper(II) sulfate. Reducing sugars react with the copper ions, resulting in a color change from blue to green, yellow, orange, or red depending on the concentration of the sugar.

The color change in Benedict's test is due to the reduction of copper(II) ions to copper(I) oxide, which forms the colored precipitate.

Detects the presence of ketoses (sugars with a ketone group). The sample is reacted with resorcinol and concentrated hydrochloric acid, which hydrolyzes polysaccharides and oligosaccharides to simpler sugars and then forms furfural from ketoses, resulting in a red color.

A test for monosaccharides (simple sugars like glucose and fructose). It uses Barfoed's reagent, which contains copper(II) acetate in acetic acid. Monosaccharides reduce the copper ions, resulting in a red precipitate.

A specific test for starch. When iodine solution is added to a solution containing starch, a distinctive blue-black complex forms due to the interaction of iodine molecules with the helical structure of starch.

The iodine solution acts as an indicator. It interacts with the helical structure of starch molecules, forming a blue-black complex that indicates the presence of starch.

Reducing sugars are carbohydrates that can donate electrons to other molecules, such as copper ions in Benedict's reagent. They have a free aldehyde or ketone group that can react with another molecule.