Carbohydrates and Lipids

Transcription

1 Carbohydrates Carbohydrates and Lipids Carbohydrates are organic compounds made of carbon, hydrogen and oxygen CHO Basic carbohydrates are created by photosynthesis, but can be rearranged and altered later Carbohydrates are the primary food source for cells Types of Carbohydrates Sugars, starches and fibers are common examples of carbs; Carbohydrates can be lumped into two major groups: - Simple Carbohydrates - Complex Carbohydrates Simple Carbohydrates Simple carbohydrates are smaller molecules made of one or two sugar molecules Monosaccharide single sugars (saccharide means sugar) Disaccharide molecules made of two sugar molecules bonded together Examples of Simple Carbohydrates Monosaccharides: Most common sugars have the formula C6H12O6 - Glucose: most abundant, easiest for the cell to process - Fructose: fruit sugar, sweetest - Galactose: found in milk sugar Disaccharides: - Sucrose: normal table sugar (gluc + fruc) - Lactose: milk sugar (gluc + galac) - Maltose: malt sugar (gluc + gluc) Examples of Simple Carbohydrates Note that simple carbohydrates end with -ose 1

2 Complex Carbohydrates Complex carbohydrates are long chains of 20 to thousands of sugars called polysaccharides - Starches: used by plants to store glucose - Glycogen: used by animals to store glucose (found in liver and muscle) - Fiber: used in plant structure, not digestible Examples of Complex Carbohydrates Plant starches Non-Energy Uses Lipids Carbohydrates aren t only used for energy In plants carbs can be used for structure (cellulose...big part of cell wall and wood) Short glucose chains can signal a cell s type or provide information to other cells Lipids are hydrocarbon molecules that are insoluble in water, like fats, oils and waxes Lipids are created by concentrating the energy found in other energy containing compounds Lipids are primarily for storing energy for use later Types of Lipids Most lipids can be lumped into the following major groups: - Triglyercides: used for energy - Phospholipids: used in cell membranes - Sterols: used for body messaging Triglycerides Made of a glycerol (simple sugar) with 3 fatty acids linked to it Fatty acids are hydrocarbon chains - Saturated: more hydrogen, solid at room temperature, animal fat - Unsaturated: less hydrogen, liquid at room temperature, plant oil 2

3 Phospholipids Sterols Phospholipids are the main component of cell membranes They are like triglycerides except one fatty acid tail is replaced with a phosphate group (PO4) Sterols are primarily used for body signaling such as hormones - Steroids: not just about muscles - Cholesterol: helps build cell membrane and is a starting point for making other sterols Proteins Proteins and Nucleic Acids Controlling the cell s activities Proteins are organic compounds made of carbon, hydrogen, oxygen and nitrogen (CHON) You might think of proteins from a dietary prospective, but they are some of the most important compounds in a cell Proteins can have roles in structure, action, regulating cell reactions and more Protein Jobs Structure: proteins can build cell parts or even body parts (like fingernails) Action: Cell movement is based on proteins. Organisms move with muscles, which are mostly protein Chemical Reactions: reactions in the cell are started and stopped by proteins called enzymes Everything the cell does is based on what proteins are working at that time Amino Acids Amino acids are the building blocks of proteins The order of amino acid in a protein chain determine the protein s shape and function You body can make some amino acids, but others, called essential amino acids, must come from you diet 3

4 Amino Acid Structure Protein Structure Amino = nitrogen group Acid = carboxylic acid R-Group = determine which amino acid it is Primary Structure: order of amino acids Secondary Structure: folding of the chain into zig-zags and coils Tertiary Structure: additional folding of the zig-zags and coils Quaternary Structure: chains linking to make the completed protein Nucleic Acids Nucleic acids are organic compounds made of carbon, hydrogen, oxygen, nitrogen and phosphorous (CHONP) Nucleic acids have more defined and specific roles than the other macromolecules Nucleic acids: primary carry genetic information for making proteins Nucleotide Structure Phosphate backbone of strand Sugar Ribose (RNA) or Deoxyribose (DNA Base gives the letter of the nucleotide; the code part Nucleotide Chains DNA and RNA chains are formed by linking nucleotides into long threads. DNA is doubled stranded the two strands match up with each other 4

5 Types of Nucleic Acids DNA: instructions for how to make the proteins RNA: helps DNA make proteins Small nucleic acids: one or two modified nucleotides used fro energy and delivery or signaling (ex. ATP, GTP) Comparing DNA and RNA Nucleic Acid DNA RNA Sugar Deoxyribose Ribose Structure Double strand Single strand Bases A, T, C, G A, U, C, G 5