Photosynthesis & Respiration

ATP, Photosynthesis, &
Cellular Respiration
Chapter 9 Notes
ATP is the high energy
organic molecule used by all
cells to perform their daily
ATP stands for
What is the structure of ATP?
ATP consists of an adenine molecule, a
ribose sugar, and 3 phosphate groups
(draw in notes from the board)
Copyright Cmassengale
What Does ATP Do for You?
It supplies YOU with ENERGY!
Copyright Cmassengale
Where is the energy found in the
ATP molecule?
The energy in ATP is stored in the
bonds between the phosphate
Chemical Bond Demonstration!
• Chemical bonds are like stretched rubber bands
– They are full of potential energy and when you release
the rubber band all of that energy is released!
How do you release that energy?
• Breaking the
bonds between
the last two
releases the
energy so the
cell can use it!
What breaks the bond?
-An enzyme called ATPase breaks
the bond
- When a phosphate is removed
from ATP the molecule ADP
(adenosine diphosphate) is formed
and energy is released
So now we have a bunch of ADP in the
cell. But the cell needs a constant supply
of energy which it gets from ATP!!!!
So how do we remake ATP from
Another enzyme called ATPsynthase is
used which puts the phosphate back on!
ATP to ADP Cycle
• Draw From Board
ATP is made all of the time
in cells
- The process that
makes ATP is called
Cellular Respiration
- Cellular respiration
occurs in both
plants & animals
ATP to ADP Cartoon Activity
• Read the information and follow the
• Use the example on the board as a guide
• Color your cartoon.
9.2 Notes: Photosynthesis
Photosynthesis is one of the most important
chemical reactions on our planet
What is Photosynthesis?
Photosynthesis is a chemical
reaction process that
autotrophs like plants must do
to make the sugar glucose.
Glucose is then used to make
ATP in cellular respiration
Defining Photosynthesis
• It is the process
of changing light
energy into
chemical energy
–The chemical
energy is the
(sugar) glucose
The equation for the chemical
reaction of photosynthesis
• DRAW from board into notes
Where does photosynthesis happen?
• Photosynthesis
happens in the
chloroplasts of
• The green
chlorophyll which
absorbs light
energy is the main
pigment in
Diagram of key parts in photosynthesis
draw from board
Why is photosynthesis important?
1) It provides plants with glucose
2) Animals eat the plants which supplies
animals with glucose - Plants are the first
step in the energy pyramid
3) The oxygen released during
photosynthesis is used by all living things
to do aerobic respiration
4) It removes carbon dioxide form the
atmosphere and keeps the carbon cycle in
Waterweed Simulation Lab
• What factors affect photosynthesis?
• Measuring amount of photosynthesis by
counting the bubbles of oxygen produced
by waterweed (elodea plant)
• Looking at three factors:
– Light color
– Light intensity
– Carbon dioxide levels
Notes 9.3 Cellular
Cellular respiration is the process of making
ATP from glucose.
What is Cellular Respiration?
Once glucose is acquired either by
photosynthesis or consuming other
organisms, an organism has to
transform the glucose energy into a
form that can be used by the organism
called called ATP. This process is
called cellular respiration
Facts about Cellular Respiration
1) It is the breakdown of glucose molecules to
make ATP
2) Takes place in all living things
3) May use oxygen - called AEROBIC
– Very efficient makes 36 ATP per glucose
4) May not use oxygen – called ANAEROBIC
– Not efficient: only 2 ATP per glucose
Facts about Aerobic respiration
1) Must have oxygen!
2) Very efficient – best way to make ATP
because it makes a net of 36 ATP!
3) Must have mitochondria to do it!
What is the chemical equation
for aerobic cellular respiration?
• Draw from board
Steps in Aerobic Cellular Respiration
1. Glycolysis
2. Citric Acid
Cycle (Krebs
3. Electron
chain (E.T.C.)
Oxygen # of net
cytoplasm Anaerobic
mitochondria Aerobic
Total ATP
What happens during aerobic
• Draw from board
But what happens if no oxygen is
present, our cells run out of oxygen
or an organism doesn’t have
mitochondria like bacteria?
Without oxygen, cells have to make
ATP anaerobically in ANAEROBIC
RESPIRATION also called
Facts about Anaerobic Respiration
1) Only way organisms like yeast (a eukaryote)
and bacteria (prokaryotes) can make ATP!
2) No oxygen required!
3) Very inefficient – only 2 ATP produced instead
of 36!
4) Another term for anaerobic respiration is
Facts about Fermentation
Type 1) Lactic acid fermentation- happens in our
muscle cells run out of oxygen
– Produces only 2 ATP
– Produces painful buildup of lactic acid in our cells
Type 2) Alcoholic fermentation – done by yeast
and one way to make beer and wine.
– Produces carbon dioxide (beer bubbles) and
– Produces only 2 ATP