1. Cell Processes

2. 1. Chemical reactions take place inside cells
There are more than 120 elements-25 are needed for life
Water is needed for chemical reactions. About 2/3 of every cell is water
Many form the 4 basic molecules for life
Carbohydrates-sugar and starch used for quick energy
Lipids-fats, oils and waxes needed for stored energy
Proteins- for the growth and repair of tissues and to fight infections
Nucleic Acids-DNA and RNA that have instructions for everything-especially reproduction

3. 2. Cells and Energy
a. All cells need energy. Chemical energy is stored in the bonds of molecules like glucose.
b. Photosynthesis
A process used by plants and other autotrophs to convert the energy of sunlight into sugars.
It requires sunlight, water, and carbon dioxide.
It occurs in the leaves of plants in organelles called chloroplasts.

4. EQUATION FOR PHOTOSYNTHESIS
WATER
OXYGEN
6CO2 +
6H2O +
ENERGY
C6H12O6 +
6O2
CARBON DIOXIDE
GLUCOSE

5. c. Cells release energy in two ways
Cellular Respiration-cytoplasm and mitochondria converts glucose into energy, CO2 and water
Fermentation-allows cells to release energy without oxygen
Alcoholic fermentation- makes alcohol
Lactic Acid fermentation- makes lactic acid; milk , cheese and sore muscles

6. EQUATION FOR RESPIRATION
CARBON DIOXIDE
GLUCOSE
C6H12O6 +
6O2
6CO2 +
6H2O +
ATP
OXYGEN
ENERGY
WATER
*Photosynthesis and Cellular Respiration are opposite processes

7. 3. Transport through cell membranes
a. Certain things MUST enter the cell for it to survive. This can occur in 2 major ways:
1. PASSIVE TRANSPORT -requires no energy
2. ACTIVE TRANSPORT-requires energy

8. b. Important Molecules that move through cell membranes
Oxygen
Carbon dioxide
Water

9. c. Types of Passive Transport 1
c. Types of Passive Transport 1. Diffusion- molecules move from a higher concentration to a lower one. It does not require energy so it is passive
Cell membrane
Outside cell
Inside cell

10. Diffusion through a membrane
Cell membrane
diffusion
Outside cell
Inside cell

11. Diffusion through a membrane
Cell membrane
Outside cell
Inside cell
EQUILIBRIUM

13. 2. Osmosis-diffusion of water across the cell membrane (also passive)
The Plasma Membrane
4/12/2018
2. Osmosis-diffusion of water across the cell membrane (also passive)
High H2O potential Low solute concentration
Low H2O potential High solute concentration
G. Podgorski, Biol. 1010

14. Diffusion of Liquids The Plasma Membrane 4/12/2018
G. Podgorski, Biol. 1010

15. d. Types of Active Transport
The movement from lower concentration to higher concentration
Active transport requires the use of energy
2 ways that materials are moved
1. Endocytosis -very large molecules are brought into the cell
2. Exocytosis-materials are moved out of the cell (usually wastes)

16. 4. What affects Transport of materials?
Temperature
Size of materials
Surface area of a cell*
Volume*
*The surface area can sometimes increase faster than the volume or the cell’s ability to hold materials so it stops growing
Cell Shape

17. SUMMARY
Cells need four large molecules to function: Carbohydrates, lipids, proteins and nucleic acids.
2/3 of all cells are water
Cells capture energy through photosynthesis and release energy through cellular respiration and fermentation
Materials are moved from areas of high concentration to low concentration through passive transport that does not require energy. Diffusion and osmosis are examples.
In active transport, energy is required to move materials from areas of low concentration to high concentration. Endocytosis and exocytosis are examples
Things that affect transport are: shape, size, volume, surface area, material size and temperature