September 11, 2013 What are some things that living things depend on that are not living?

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Today’s Objective Identify macromolecules essential to life Identify the properties of what that make it so important to life

Macromolecules Large molecules made up of smaller subunits called monomers There are four major bio-molecules Carbohydrates Proteins Lipids Nucleic acids

Carbohydrates Supplies energy to cells Monomers = sugar (glucose) Polymers = starch

Plant Starch Cellulose Tough fibers that give plants structure Wood/paper

Chitin: form of cellulose Hard exoskeleton of insects and crustaceans

Animal Starch Glycogen Stored sugar released from your liver when the glucose in your blood runs low Supplies your muscles with energy for contraction/movement

Unsaturated fat and fatty acid Saturated fat and fatty acid Lipids Unsaturated fat and fatty acid double bond causes bending Less Hydrogen Store energy Insulate/protect Saturated fat and fatty acid Filled with Hydrogen

Phospholipids Make up the cell membrane Allows molecules in and out of cell Hydrophilic head WATER Hydrophobic tail Figure 5.14

Nucleic Acids DNA and RNA Store vital information in each cell for making proteins Made of nucleotides

Proteins Wide variety: combo of amino acids (20) Carry out chemical reactions Transport molecules Fight diseases

Protein Structure… Determines Function

Enzymes

What monomers are bonded together to form proteins? Nucleotides Amino acids Fatty acids Glucose

This macromolecule is the main source of energy for living things. Lipids Protein Carbohydrate Nucleic Acid

What macromolecule is DNA an example of?

This macromolecule controls the rate of reactions and regulate cell processes

What macromolecule would you typically find in this food?

How about this food?

And this?

2-2 Properties of Water Polarity– unequal sharing of electrons between. creates a slight charge Hydrogen end = positive Oxygen end = negative

Cohesion Attraction between molecules of the same substance Water molecules produce Surface Tension May support light objects

Watery Examples

Adhesion Attraction between molecules of different substances Capillary Action Causes water to rise in a narrow tube against gravity

Water conducting cells Capillary Example Helps pull water up through the microscopic vessels of plants Water conducting cells 100 µm Figure 3.3

Mixtures Involving Water Solutions: all components are evenly distributed Solute—substance dissolved Solvent—substance which dissolves solutes

Suspensions Mixtures of water and nondissolved material Small pieces that do not settle out

Acids, Bases, and pH Acids: compounds that contain higher concentrations of H+ ions than pure water pH values below 7 Bases: compounds that contain low concentrations of H+ and high amounts of OH- ions pH values above 7

pH Scale (potential of Hydrogen)