Download Photosynthesis and Cellular Respiration

Photosynthesis and Cellular
Respiration
The building and breaking down
of glucose
Photosynthesis
The process in which plants obtain
energy from sunlight and transform it
into chemical energy
Autotrophs –are able to undergo PSNplants, algae, and some bacteria
The ultimate source of energy is
sunlight
PSN continued
Goal of the process: GLUCOSE (for energy)
Plants need CO , H 0, and Light
End Result – O and C H O (Glucose)
2
2
2
6
12
6
PSN Equation
6H O + 6CO
2
2
+ Light 
C H O + 6O
6
12
6
Takes place in the chloroplast
Chlorophyll (green pigment) and other
pigments are the chemicals that allow
absorb light to form energy
2
PSN Equation…
6H2O + 6CO2 + Light 
Reactants
Water
Carbon Dioxide
Light energy
C6H12O6 + 6O2
Products
Glucose
Waste product –
Oxygen
The waste oxygen
ultimately comes
from the water
molecule
Parts of PSN
Light Absorption
The pigments absorb the light in the cholorophyll
Electron Transport Chain
The light “excites” electrons. The electrons are
passed on and on giving off energy every time
they switch hands, eventually forming a chemical
called NADPH.
Calvin Cycle
NADPH enters the Calvin Cycle. After a series of
reactions the NADPH is converted to Glucose
Light
White light from the sun is a
combination of colors – visible spectrum
Result
Substances can reflect, absorb, or transmit the
different colors
The color of an object is the result of that
object reflecting a certain color.
i.e. chlorophyll absorbs reds and blues and
reflects green.
Cellular Respiration
The process of breaking down glucose to
obtain energy in the form of ATP
Has two parts:
Glycolysis
Fermentation / Aerobic Respiration
6O + C H O  6CO + 6H O+ Energy (ATP)
2
6
12
6
2
2
OPPOSITE OF PHOTOSYNTHESIS
Glycolysis
The first stage of Cell Respiration
A glucose molecule is broken down into
two pieces called pyruvate
Doesn’t need oxygen
Occurs in the cytoplasm
End Result 2 ATP molecules
If Oxygen is Present
Aerobic Respiration – oxygen present
Pyruvate enters into the Krebs Cycle
Series of reactions yields other chemicals
(NADPH) that will be used later and ATP
Electron Transport Chain –
The chemicals produced in the Krebs Cycle are
used to pass electrons down a long series of
acceptors
End result  34 ATP molecules
If Oxygen is Absent
Pyruvate enters into Fermentation
Fermentation converts pyruvate into other
chemical compounds that do not yield ATP
but other chemicals that the body can use.
Example: Lactic Acid when not enough
Oxygen present the body converts
pyruvate into Lactic Acid= sore muscles
Glucose
Glycolysis
Oxygen Absent
Fermentation
2 ATP
Oxygen Present
Aerobic Respiration
(anerobic)
34ATP