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Lipids. Lipids include fats and oils. Fats are solid at room temperature. Oils are liquids at room temperature. In living organisms, lipids form part of the structure of cell membranes. Extra food that is not immediately needed as a source of energy is changed to fat and stored.
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Lipids • Lipids include fats and oils. • Fats are solid at room temperature. • Oils are liquids at room temperature. • In living organisms, lipids form part of the structure of cell membranes. • Extra food that is not immediately needed as a source of energy is changed to fat and stored. • Lipids are a source of stored energy in living organisms.
Lipids • Lipids contain 9 kcal of energy per gram. • Lipids, like carbohydrates, contain the elements carbon, hydrogen, and oxygen. • The building blocks of lipids are fatty acidsand glycerol.
Lipid FunctionsPlease add this information in your notes. • Triglycerides are used for long-term energy storage and insulation (this is fat in the body) • Phospholipids make up the cell membrane in all living cells. • Sphingolipids and cholesterol are part of the cell membrane, holding it together. • Hormones and steroids are used in cell signaling (like testosterone and estrogen, among others).
Proteins • Proteins form important cell products such as enzymes, hormones, antibodies, and hemoglobin. • Proteins also play an important role in cell repair and growth. • Proteins are made up of carbon, hydrogen, oxygen, and nitrogen. • Some proteins also contain sulfur. • Proteins contain 4 kcal of energy per gram.
Proteins • Proteins are composed of simpler units (building blocks) called amino acids. • There are twenty amino acids found in living organisms. • Amino acids can be joined together in any sequence and combination. • In a human being, there are approximately 50,000 different proteins
Proteins • Two amino acids bonded together form a dipeptide. • Many amino acids bonded together form polypeptides. • Proteins are made up of long polypeptide chains.
Proteins http://www.learner.org/channel/courses/biology/archive/animations.html http://www.stolaf.edu/people/giannini/flashanimat/proteins/protein%20structure.swf
Protein Structure Four Structures: • Primary • Secondary • Alpha helix • Beta Sheet • Tertiary • Quaternary
Nucleic Acids • Nucleic acids are very large molecules made up of carbon, oxygen, nitrogen and phosphorus. • The simplest unit or building block of nucleic acids is the nucleotide. • Nucleotides are composed of a sugar molecule, a nitrogen base, and a phosphate group.
Nucleic Acids • DNA and RNA are two kinds of nucleic acids. • DNA makes up genes and is involved in heredity. • RNA is involved in the making of proteins.