Do Now!!  What is energy?  What is the ultimate source of energy on the earth?  Where do we get our energy from?  What is energy?  What is the ultimate source of energy on the earth?  Where do we get our energy from?

Objectives  To define energy.  To list the different types of energy.  To explain the laws of thermodynamics.  To begin discussing photosynthesis and cellular respiration  To define energy.  To list the different types of energy.  To explain the laws of thermodynamics.  To begin discussing photosynthesis and cellular respiration

Section 8.1: How organisms obtain energy!!

So what is energy??  Energy-  The ability to do work!!  Thermodynamics-  is the study of the flow and transformation of energy in the universe.  Energy-  The ability to do work!!  Thermodynamics-  is the study of the flow and transformation of energy in the universe.

3 Types of Energy Potential Kinetic Chemical

3 Types of Energy 1. Potential - stored energy, or energy of position  Ex: top of the rollercoaster! 2. Kinetic - motion  Ex: moving down from top of rollercoaster! 3. Chemical - energy found in bonds (released when bonds are broken, stored when bonds are formed)  Ex: lighting a match (released or stored?) 1. Potential - stored energy, or energy of position  Ex: top of the rollercoaster! 2. Kinetic - motion  Ex: moving down from top of rollercoaster! 3. Chemical - energy found in bonds (released when bonds are broken, stored when bonds are formed)  Ex: lighting a match (released or stored?)

Laws of Thermodynamics  First law —energy can be converted from one form to another, but it cannot be created or destroyed.  Ex. Stored energy to chemical energy to mechanical energy  First law —energy can be converted from one form to another, but it cannot be created or destroyed.  Ex. Stored energy to chemical energy to mechanical energy

Laws of Thermodynamics  Second law —energy cannot be converted without the loss of usable energy.  Ex. Energy lost as heat  Second law —energy cannot be converted without the loss of usable energy.  Ex. Energy lost as heat

Review of Reactions…  Endothermic - uses energy to make bonds  H + H H 2 Energy put in  Exothermic - breaks bonds and releases energy  H 2 H + H Energy Released  Endothermic - uses energy to make bonds  H + H H 2 Energy put in  Exothermic - breaks bonds and releases energy  H 2 H + H Energy Released

Autotrophs and Heterotrophs o Autotrophs: make their own energy Ex: o Heterotrophs: have to eat to obtain energy Ex: o Autotrophs: make their own energy Ex: o Heterotrophs: have to eat to obtain energy Ex:

Metabolism  Metabolism:  All chemical reactions in a cell  Two types of Metabolic Pathways:  Catabolic : Release energy by breaking down larger molecules  Anabolic : Use energy to build larger molecules from smaller ones  Metabolism:  All chemical reactions in a cell  Two types of Metabolic Pathways:  Catabolic : Release energy by breaking down larger molecules  Anabolic : Use energy to build larger molecules from smaller ones

Think- Pair - Share  Of the following examples, list which ones are catabolic and anabolic  1. Amino acids becoming polypeptide chain  2. Glucose becoming glycogen  3. Your body breaking down food  4. Lifting weights and building up muscle mass  Of the following examples, list which ones are catabolic and anabolic  1. Amino acids becoming polypeptide chain  2. Glucose becoming glycogen  3. Your body breaking down food  4. Lifting weights and building up muscle mass

Adenosine Tri Phosphate (ATP)  ATP : most important biological molecule that provides chemical energy  Structure:  Adenine base, ribose sugar, and 3 phosphate groups  Function: Releases energy when bonds are broken  ATP : most important biological molecule that provides chemical energy  Structure:  Adenine base, ribose sugar, and 3 phosphate groups  Function: Releases energy when bonds are broken

Processes involving Energy…  Cellular respiration —organic molecules are broken down to release energy for use by the cell -type of process:  Photosynthesis —light energy from the Sun is converted to chemical energy for use by the cell -type of process:  Cellular respiration —organic molecules are broken down to release energy for use by the cell -type of process:  Photosynthesis —light energy from the Sun is converted to chemical energy for use by the cell -type of process:

Next up… Photosynthesis!!