Glucose Molecule

Chapter 2 – Cell Processes and Energy Cell Processes Include: Photosynthesis Respiration Cell Division – mitosis (all cells except sex cells) Cell Division – meiosis (to produce sex cells)

Photosynthesis Process by which a cell captures energy from sunlight and uses it to make food. Carbon dioxide + water + sunlight = sugar + oxygen 3

Photosynthesis What types of organisms use the energy in sunlight to make their own food? Plants Algae Some Bacteria 4

Photosynthesis – Chemical Equation Write the chemical equation for photosynthesis 5

In this equation, one of the raw materials of photosynthesis is 6 molecules of carbon dioxide (CO2). How many carbon atoms are in 6 molecules of CO2? ____ How many oxygen atoms are in 6 molecules of CO2? ____ 6 12

Cellular Respiration – Chapter 2, Section 2 What is cellular respiration as it relates to cells? Process by which cells obtain energy from glucose. Cells break down sugar molecules and release the energy stored in the bonds. Occurs mostly in the mitochondria.

Cellular Respiration 8

Cellular Respiration – Chemical Formula Write the equation for cellular respiration C6H12O6  + 6O2 -----> 6CO2  + 6H20 + energy (ATP) (sugar) (oxygen) (carbon dioxide) (water) Sugar (glucose) is broken down into carbon dioxide and water. Chemical energy (ATP) is released 9

C6H12O6  + 6O2 -----> 6CO2  + 6H20 + energy (ATP) (sugar) (oxygen) (carbon dioxide) (water) In this equation, one of the products of respiration is 6 molecules of water (H2O). How many hydrogen atoms are in 6 molecules of (H2O)? ___ How many oxygen atoms are in 6 molecules of(H2O)? ___ 12 6

Cellular Respiration – 2 stages Where does the first stage of cellular respiration take place? In the cytoplasm What happens during this stage? The glucose molecule C6H12O6 is broken into smaller molecules. A small amount of energy is released. 11

Cellular Respiration – 2 stages Where does the second stage of cellular respiration take place? In the mitochondria What happens during this stage? The smaller molecules are broken down even more. Oxygen is required for this step. A great deal of energy is released. 12

Lets compare…. Photosynthesis: 6CO2 + 6H2O --------> C6H12O6 + 6O2 sunlight Cellular Respiration: C6H12O6  + 6O2 -----> 6CO2  + 6H20 + energy (ATP) 13