Biology 8 - Unit 02: Biomolecules

Study Notes

The unit focuses on biomolecules, including carbohydrates, lipids, nucleic acids, and proteins.
Living things need biomolecules for various processes such as energy storage, providing structure, and controlling chemical reactions.
Biomolecules are organic compounds, largely composed of carbon, hydrogen, oxygen, nitrogen, and phosphorus.

Carbohydrates are the most common organic molecules, providing the main energy source to the body.
The chemical structure is C, H, O (1:2:1 ratio)
Monosaccharides are the basic building block (glucose, fructose)
Disaccharides are two monosaccharides combined (maltose, sucrose).
Polysaccharides such as starch (plant energy storage), glycogen (animal energy storage), cellulose (structural support in plants, found in cell walls), and chitin (found in exoskeletons of insects and some fungi).

Lipids store energy, insulate the body, and are a major component of cell membranes.
Lipids are hydrophobic (do not dissolve in water)
The chemical structure is largely composed of C, H, O. The proportion of hydrogen to carbon atoms is greater than in carbohydrates.
The basic building block is glycerol and 3 fatty acids.
The main types are phospholipids, triglycerides (fats and oils), steroids (e.g., cholesterol), and waxes.
Saturated fats have single bonds between carbon atoms, are solid at room temperature (largely animal fats).
Unsaturated fats have double or triple bonds between carbon atoms, are liquid at room temperature (largely plant-based fats).

Proteins are essential for transporting molecules into and out of cells, controlling chemical reactions, providing for structure and growth.
Proteins are made up of amino acids (20 different ones).
Examples of proteins include hemoglobin (in red blood cells), albumin (in eggs), enzymes, and antibodies.

Nucleic acids, such as DNA and RNA, provide genetic information, and instruct the body on how to make proteins.
A nucleotide is the most basic building block of Nucleic Acids. A nucleotide consists of a sugar, phosphate, and nitrogenous base.
Elements include: C, H, O, N, and P
Found in DNA, RNA, ATP