biology unit 4

Biomolecules - Biology Unit 3
What is a Biomolecule?
Organic molecule made by living organisms
Organic Molecules: contain carbon considered the “chemicals of life”
Inorganic Molecules:
Do not contain carbon
Consist mostly of: carbon (c), hydrogen (h), oxygen (o)

Monomers vs. Polymers
Monomers:
single-molecule that may react with similar molecules to form a chain

Polymers: a chain of many monomers that are chemically bonded together.
How are polymers formed?
Dehydration Synthesis (Condensation): two hydrogen atoms and one oxygen atom are removed from the monomers to form water, and the two monomers are joined together.
How are polymers broken down?
Hydrolysis—the reverse of dehydration synthesis (condensation) the reverse of dehydration synthesis.
Water added to the polymer, unlinking the chain and breaking it back down to its original monomer units.
Carbohydrates
Group of organic molecules that includes: group of organic molecules that includes sugars, starches, and cellulose.
Structure:
carbon, hydrogen, and oxygen in a 1:2:1
(CH2O)n – n is an integer such as 5 (C5H10O5)
Subunits: Monosaccharides
Most often in a: Ring shape
Subunits are connected with: covalent bonds
Function:
Energy
Stucture Support
Cell Wall
Cell Membrane Marker

Lipids organic molecule group including fats and phospholipids
Structure:
Subunits:
Glycerol of fatty acids
Glycerol and fatty acids plus:
Insoluble in water
Do not form large polymers (2 or 3 fatty acids with glycerol)
Examples: diglyceride and triglyceride
Function:
energy storage insulation Part of cell membrane (phospholipids) hormones Proteins group of organic molecules that provides structure and facilitates chemical reactions

Structure:
Subunits: monomers: amino acids
Amino acids connect via:
Very large molecules
Globular or structural least likely to be affected by order of single-molecule units
Function:
Lots of functions!
Enzymes (speed rate of chemical reactions)
Structural components in cells mechanical funtions in muscles and cytoskeleton (internal cell framework)
Cell signaling immune response

Nucleic Acids Group of organic molecules including DNA and RNA
Structure:
Subunits are nucleotides— 5-carbon sugar, nitrogen base and one or more phosphate groups
Most likely to be affected by order of single-molecule units
Function:
Storage and retrieval of information: encode genes gene expression