BELL WORK Energy Thermodynamics Metabolism Photosynthesis DEFINE the following Terms Energy Thermodynamics Metabolism Photosynthesis Cellular respiration Adenosine tri-phosphate (ATP)

How Organisms Obtain Energy Chapter 8 Section 1

All living organisms use energy to carry out all biological processes Main Idea All living organisms use energy to carry out all biological processes

Transformation of Energy Chemical reactions & processes in your cells are ongoing; constantly using energy Macromolecules are assembled and broken down substances are transported across cell membranes genetic instructions are transmitted

All of these cellular activities require ENERGY—the ability to do work. Thermodynamics is the study of the flow and transformation of energy in the universe

Laws of Thermodynamics Energy can be converted from one form to another, but it cannot be created nor destroyed Energy cannot be converted without the loss of useable energy Lost energy is usually converted to thermal energy Entropy is the measure of disorder, or unusable energy, in a system

Autotrophs Organisms that make their own food Can you give an example of an Autotroph?

Autotrophs convert light energy for the sun into chemical energy These are organisms that perform Photosynthesis Directly or indirectly nearly all the energy for life comes from the sun

Heterotrophs Organisms that need to ingest food to obtain energy Can you give an example of a Heterotroph?

Metabolism All the chemical reactions that take place in a cell is referred to as the cell’s metabolism

A series of chemical reactions in which the product of one reaction is the substrate for the next reaction is called a metabolic pathway Catabolic release energy by breaking down large molecules into smaller ones Anabolic uses energy that is released by the catabolic pathway to build larger molecules from smaller ones

Photosynthesis Photosynthesis is the anabolic pathway in which light energy from the sun is converted to chemical energy for use by the cell 6CO2 + 6H2O  C6H12O6 + 6O2

Cellular Respiration Cellular Respiration is the catabolic pathway in which organic molecules are broken down to release energy for use by the cell C6H12O6 + 6O2 6CO2 + 6H2O + Energy

ATP: The Unit of Cellular Energy In living organisms, chemical energy is stored in biological molecules and can be converted into other forms of energy when needed Adenosine Tri-phosphate (ATP) is the most important biological molecule that provides chemical energy

ATP Structure ATP is the most abundant energy-carrier molecule in cells ATP is a nucleotide made of an adenine base, a ribose sugar, and 3 phosphate groups

ATP Function ATP releases energy when the bond between the 2nd and 3rd phosphate group is broken This breakage forms adenosine Di-phosphate (ADP)

ATP ADP

HOMEWORK QUESTIONS: Due 9-27-10 Identify the major source of energy for living organism. Describe an example of the first law of thermodynamics. Compare and contrast anabolic and catabolic pathways. Explain how ATP stores and releases energy

Explain/Describe how ATP works within a cell. Ticket Out the Door Explain/Describe how ATP works within a cell.