3.1 Synthesis of Biological Macromolecules
Biological macromolecules are large molecules necessary for life and include carbohydrates, lipids, nucleic acids, and proteins.
In dehydration synthesis, monomers combine with each other via covalent bonds to form polymers.
Hydrolysis reactions result in the breakdown of polymers into monomers by using a water molecule and an enzymatic catalyst.
Carbohydrates are essential macromolecules that are classified into three subtypes: monosaccharides, disaccharides, and polysaccharides.
Benefits of Carbohydrates
Carbohydrates are a major class of biological macromolecules that are an essential part of our diet and provide energy to the body.
Fats and Oils
Fats and oils, which may be saturated or unsaturated, can be unhealthy but also serve important functions for plants and animals.
Waxes are nonpolar lipids that plants and animals use for protection and have many functions in society.
Phospholipids are amphipathic molecules that make up the bilayer of the plasma membrane and keep the membrane fluid.
Steroids, like cholesterol, play roles in reproduction, absorption, metabolism regulation, and brain activity.
Types and Functions of Proteins
Proteins perform many essential physiological functions, including catalyzing biochemical reactions.
An amino acid contains an amino group, a carboxyl group, and an R group and combines with other amino acids to form polypeptide chains.
Each successive level of protein folding ultimately contributes to its shape and therefore its function.
Denaturation and Protein Folding
Denaturation is a process in which proteins lose their shape and, therefore, their function because of changes in pH or temperature.
3.5 Nucleic Acids
DNA and RNA
DNA is a nucleic acid that controls all cellular activities, while RNA creates the proteins that makes these events occur.
DNA Double-Helix Structure
The DNA double helix looks like a twisted staircase, with the sugar and phosphate backbone surrounding complementary nitrogen bases.
RNA is the nucleic acid that makes proteins from the code provided by DNA through the processes of transcription and translation.