chapter+8+notes


 * __*Chapter 8- Section 1 Notes*__

//Section 1- How Organisms Obtain Energy//** -__Energy__ is the ablility to do work. -Chemical Potential Energy (think of it as a loaded spring)
 * **Transformation of Energy**
 * -**__Thermodynamics__ is the study of the flow and transformation of energy in the universe.

-__First law__ - energy can be converted from one form to another, but it //cannot// be created nor destroyed. -__Second Law__ - energy cannot be converted without the loss of usable energy (heat, friction, sound, light, etc.)
 * **Law of Thermodynamics**

-__Autotrophs__ are organisms that make their own food. Examples: plants, some protists (algae), and some bacteria. -__Heterotrophs__ are organisms that need to ingest food to obtain energy. Examples: animals, fungi, some protists (amoeba, paramecia), and some bacteria.
 * **Autotrophs and Heterotrophs**

-All of the chemical reactions in a cell. -__Photosynthesis__ - light energy from the Sun is converted to chemical energy (glucose) for use by the cell -__Cellular respiration__ - are broken down to release energy for use by the cell. -Glucose - C6H12O6 CH20
 * Metabolism

-__ATP__ - the "energy currency" of the cell. -ATP stands for Adenosine Triphosphate -ATP stores and releases a small amount ($1) of energy for movement, transport and other active processes in the cell. -Both heterotrophs and autotrophs use ATP as an energy storage molecule in their cells. -ATP is used to power processes in the cell such as the Calvin Cycle of photosynthesis in which CO2 is converted into glucose. -Atp is also used for movement within the cell. -It is produced during cell respiration when carbohydrates such as glucose are broken down. -Energy is realeased when the __third phosphate__ on ATP is removes and transferred to anotoher molecule. -This leaves behind __ADP__ (adenosine diphosphate)
 * **ATP: The Unit of Cellular Energy**

__***Chapter 8- Section 2 Notes***__


 * //Section 2 -Photosynethesis//**

-__Photosynthesis__ - the process by which the energy of the sun is used to convert H2O and CO2 into high enrgy sugars (glucose). -I__mportance__ - We need glucose and other carbnohydrates for energy but we cannot produce them oursleves. We also need oxygen and this is produced during photosysnthesis by plants and algae.

-__Color__ - Reflected light. We see color. -__Pigment__ - a molecule that absorbs light. -Whatever colors the pigment does NOT absorb are what we see.
 * **Light Energy:**
 * -**Light is a form of energy that travels in the form of particles or waves. The waves are measured in wavelengths, which vary in length. Humans can see violet through red wavelengths. (Remember "ROY G BIV")

-Green is REFLECTED by cholorphyll A. That's why most leabes appear green to us. -Other pigments called __Accessory Pigments__ (cholorphyll B, xanophyll, and carotene) help cholorphylll A absorb a greater spectrum of light.
 * **Pigments:**
 * -**__Cholorphyll A__ is a pigment that ABSOBS violet, ted, and vlue wavelegnths of light.

-Photosynthesis takes place in the __chloroplast__. -A chloroplast is a double-membraned, disk-shaped organelle. -located inside this disk are stacks of stacks. -Each sack is called a __thylakoid__. -Inside each thylakoid is chlorophyll and other pigments. -Stacks of sacks are called __grana__. -Surrounding the grana is a fluid called __stroma__
 * **Chloroplasts:**