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

Photosynthesis

1.What types of organisms use the energy in sunlight to make their own food?

– Plants– Algae– Some Bacteria

Photosynthesis – Chemical Equation

2.Write the chemical equation for photosynthesis

3. In this equation, one of the raw materials of photosynthesis is 6 molecules of carbon dioxide (CO

2).

a) How many carbon atoms are in 6 molecules of CO2? ____

a) How many oxygen atoms are in 6 molecules of CO2? ____

6

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Cellular Respiration – Chapter 2, Section 2

1.What is cellular respiration as it relates to cells?During cellular respiration cells break down sugar

molecules and release the energy stored in the bonds.Occurs mostly in the mitochondria.

Cellular Respiration

Cellular Respiration – Chemical Formula

2. Write the equation for cellular respiration

C6H12O6  + 6O2 -----> 6CO2  + 6H20 + energy (ATP) (sugar) (oxygen) (carbon dioxide) (water)

Sugar is broken down into carbon dioxide and water. Chemical energy (ATP) is released

3. In this equation, one of the products of respiration is 6 molecules of water (H

2O).

a) How many hydrogen atoms are in 6 molecules of (H2O)? ___

a) How many oxygen atoms are in 6 molecules of(H2O)? ___

12

6

C6H12O6  + 6O2 -----> 6CO2  + 6H20 + energy (ATP) (sugar) (oxygen) (carbon dioxide) (water)

Cellular Respiration – 2 stages

4.Where does the first stage of cellular respiration take place?In the cytoplasm

What happens during this stage?The glucose molecule is broken in half.A small amount of energy is released.

Cellular Respiration – 2 stages

5.Where does the second stage of cellular respiration take place?In the mitochondria

What happens during this stage?The two halves of the glucose molecule are broken

down into smaller molecules.A great deal of energy is released.

Lets compare….

Cellular Respiration:

C6H12O6  + 6O2 -----> 6CO2  + 6H20 + energy (ATP)

Photosynthesis:

6CO2 + 6H2O --------> C6H12O6  + 6O2 

sunlight