Biology Notes Essay

Submitted By hdheidiquan
Words: 808
Pages: 4

Organic Compounds
Organic Compounds
All life is made from different combinations of a small set of molecules.
Almost all molecules in an organism are built around carbon.
Organic compound-a molecule consisting primarily of carbon and is made by cells.
Carbohydrates
Carbohydrates (sugars) are used for energy and can be used to create cell parts.
Monosaccharides- consist of single sugar molecules.
The main fuel source for cellular work.
Can be turned into polysaccharides.
Polysaccharides-two or more monosaccharides bonded together to form a polymer.
Polymer-a chain of repeating subunits.
Used for storing energy or building cell parts.
Lipids
Lipids-made mostly of carbon and hydrogen.
Fats and steroids.
Fat-a lipid made of glycerol and fatty acids.
Fatty acids are long chains of hydrogen and carbon.
Primarily for energy storage.
Insulation in animals.
Major component of cell membranes.
Saturated fats-the fatty acids are straight.
The C in the fatty acid are single bonded to the next.
Are solids at room temperature.
Unsaturated fats-the fatty acids are bent.
There are one or more C=C double bonds in the fatty acid.
Are liquids at room temperature.
Cholesterol-a lipid made of four rings bonded together.
Part of cell membranes.
Building blocks of hormones (chemical signals, steroids).
Waxes-are a fatty acid linked to an alcohol.
Used as waterproofing.

Nucleic Acids
Nucleic acids-polymers that allow organisms to reproduce.
Make up the genes of an organism.
DNA and RNA

Proteins
Proteins
Proteins are polymers of amino acids.
Amino acid-organic molecule made of three parts.
Amino group, carboxyl group, R-group
There are 20 different R-groups.
There are 20 different amino acids.
Used for movement, growth, structure, transport, defense, and some are hormones.
Protein Structure
Primary structure-the sequence of the amino acids.
Determines the shape and function of the protein.
Held together by peptide bonds between amino acids.
Secondary structure-segments of the chain fold into helices and pleated sheets.
Held together by H-bonds, disulfide bridges between R groups.
Tertiary structure-the overall 3-D shape of the protein.
The protein folds into its final shape.
Held together by H-bonds, disulfide bridges and attractions between R groups.
Quaternary structure-two or more proteins bond together to become functional.
Not present in all proteins.
Enzymes
Enzymes are proteins used to speed up reactions.
Holds the reactants in the proper position for the reaction to occur.
Active site-where the reactants are held.
Each enzyme catalyzes (speeds up) one reaction.
Are not changed by the reaction and can be reused.
Work best under certain conditions (optimal conditions).
Changes in temperature, pH or ionic concentration denature all proteins/enzymes.
Denature-the protein unravels.
H bonds and disulfide bridges break.
Protein can no longer do its job.
Alters the shape of the enzyme, damaging the active site.
Cannot hold the reactants.
The rate of reaction is decreased.

Cell Structure

Harvesting Energy
ATP
All living organisms use the energy stored in ATP for all of its activities.
ATP-adenosine triphosphate.
Energy stored in ATP is released when the third (terminal) phosphate group is broken off.
The breakdown of ATP is coupled to reactions that need energy to occur.
Harvesting Energy
The energy to make ATP comes from the breakdown of the food we eat.
Fermentation-the breakdown of sugar to make ATP without oxygen.
Cellular respiration-the breakdown of