Bio Study Guide PDF

Study Guide: Lipids, Proteins, and Nucleic Acids Proteins: Structure and Function Structure Determines Function: The function of a protein depends on its specific shape or structure. Peptide Bonds: Proteins are made up of amino acids, which are linked by peptide bonds....

Study Guide: Lipids, Proteins, and Nucleic Acids Proteins: Structure and Function Structure Determines Function: The function of a protein depends on its specific shape or structure. Peptide Bonds: Proteins are made up of amino acids, which are linked by peptide bonds. Types of Amino Acids: 1. Non-essential amino acids: These are produced by the body. 2. Essential amino acids: These must be obtained from food since the body cannot produce them. Enzymes: Special proteins that act as biological catalysts to speed up chemical reactions. Functions of Proteins: 1. Movement: Proteins like actin and myosin in muscles help in movement. 2. Storage: Albumen (egg white) stores proteins and nutrients for the developing embryo. 3. Transport: Hemoglobin transports oxygen in the blood. 4. Regulatory: Proteins like insulin regulate processes like blood sugar levels. 5. Structural: Keratin and collagen provide support to hair, nails, and cell membranes. Lipids: Structure and Functions Structure of Lipids: Lipids are made of 3 fatty acid molecules and 1 glycerol molecule. Fatty Acids: Lipids can have fatty acids with single bonds (saturated) or double bonds (unsaturated). Functions of Lipids: ○ Energy Storage: Long-term storage of energy. ○ Insulation: Helps maintain body temperature. ○ Protection: Shields organs from physical shock. ○ Waterproofing: Prevents water loss (e.g., in plants and animals). ○ Chemical Messengers: Includes steroid hormones like testosterone and estrogen. ○ Cell Membrane Structure: Phospholipids form the bilayer of cell membranes. Examples of Lipids: ○ Fats, oils, waxes, phospholipids, steroid hormones, and triglycerides. Nucleic Acids: DNA and RNA Types of Nucleic Acids: ○ DNA (Deoxyribonucleic Acid): Stores genetic information.  ○ RNA (Ribonucleic Acid): Involved in translating the genetic information from DNA to make proteins. Structure of DNA: ○ Double Helix: DNA has a double-helix structure made of two strands twisted together. ○ Base Pairing: In DNA: Adenine (A) pairs with Thymine (T), and Cytosine (C) pairs with Guanine (G). In RNA: Adenine (A) pairs with Uracil (U) instead of thymine. Where is DNA found?: DNA is found in the nucleus of eukaryotic cells. DNA to RNA: ○ The flow of genetic information is: DNA → RNA → Protein. ○ Central Dogma: This explains how genetic information is transferred from DNA to RNA to produce proteins. Key Concepts Lipids: Lipids are hydrophobic (do not dissolve in water) and store more energy per gram than carbohydrates or proteins. ○ Saturated fats: No double bonds; solid at room temperature. ○ Unsaturated fats: Contain double bonds; liquid at room temperature. ○ Phospholipids form the cell membrane with a hydrophobic tail and a hydrophilic head, creating the bilayer that controls what enters and exits the cell. Proteins: ○ Proteins are polymers of amino acids linked by peptide bonds. ○ Enzymes: Proteins that speed up chemical reactions. ○ Proteins have diverse roles in movement, transport, regulation, and structure. ○ Essential amino acids must be obtained from food, while non-essential amino acids are made by the body. Nucleic Acids: ○ DNA stores genetic information and is in the nucleus. ○ RNA helps execute the genetic instructions by translating DNA into proteins. ○ Nucleotides: The monomers of nucleic acids (DNA/RNA) consist of a sugar, phosphate group, and a nitrogenous base. Important Terms to Remember: Peptide Bond: The bond that links amino acids in a protein. Amino Acids: The building blocks of proteins. Enzymes: Proteins that catalyze chemical reactions. Phospholipids: Lipids that form cell membranes. Double Helix: The shape of DNA. Hydrophobic: Nonpolar, not dissolving in water (applies to lipids).  Nucleotides: The monomers of DNA and RNA. Summary of Key Concepts: Proteins: Made of amino acids; their function depends on their shape; enzymes speed up reactions. Lipids: Include fats, oils, and phospholipids; store energy, protect organs, and form cell membranes. Nucleic Acids: DNA stores genetic info, RNA helps create proteins, and both are essential for heredity and protein synthesis.