Photosynthesis
How do we grow a plant?
But is that all????
Plants need to do
Photosynthesis
Chlorophyll inside
What you don’t see…
Thylakoid: individual membranebound compartments where
photosynthesis actually occurs
(contain the photosynthetic pigments)
Granum: stacks of
thylakoids
Photosynthesis- what
goes in?
Sunlight (light Energy)
Water
H2O
Carbon Dioxide
CO2
Photosynthesis- what
comes out?
Sunlight
(Light Energy)
Glucose
C6H12O6
Water
H2O
Oxygen
Carbon Dioxide
CO2
O2
Photosynthesis



Let’s write the chemical equation on
the board!!
What are the reactants, What are the
products?
What type of energy transformations
are going on?
– Light Energy into Chemical Energy
Reaction



CO2 + H2O + light O2 + C6H12O6
But it’s not balanced
6 CO2 + 6 H2O + light 6 O2 + C6H12O6
Reactants
Products
Photosynthesis has an
“opposite” reaction…

ALL cells must perform this reaction
– (not like photosynthesis that only occurs
in autotrophs)
– Occurs in Mitochondria
– It’s why we breathe

In fact the name we give to breathing is
named after this cellular process
– Any guesses???
Cell Respiration
Carbon Dioxide
Glucose
CO2
C6H12O6
Water
H2O
Oxygen
O2
Energy
Reaction



Let’s draw the chemical formula on the
board!!
What are the reactants, What are the
products?
What type of energy transformations
are going on?
– Chemical Energy (Food) into Chemical
Energy (ATP)
Two Types of Respiration

You are currently
taking in oxygen and
burning sugars within
the mitochondria to
release chemical
energy.

This process is also
known as Aerobic
Respiration. Why?
– Because Oxygen is
present which allows
your cells to burn
glucose into energy
much more efficiently.
What would happen if your cells were
deprived of oxygen?? Would they still be
able to burn glucose to make energy??

YES!!
Anaerobic Respiration
– What does anaerobic mean?


NO OXYGEN PRESENT
Ex: Fermentation in the body cells
– Long distance runners often create an
anaerobic environment for their cells

Not a very energy efficient process & a
bad side effect is produced:

Lactic Acid
A different example of
fermentation

Breweries rely on this process:
– Yeast cells need energy to survive, so
they will breakdown sugars in anaerobic
conditions and a byproduct is alcohol.
– How do you know CO2 is produced?
Fermentation Basics

Anaerobic
Animals produce lactic acid and CO2
Plants produce ethyl alcohol and CO2

Less efficient…pgs 124-125


Efficiency of Types of Cell
Respiration
 Aerobic
respiration yields at
least 36 ATP
 Anaerobic nets a measly 2
ATP
Based on the graph, what color is
this plant:
91%
5%
5%
1. Green
2. Red
3. Violet
Based on the graph, what colors
are best absorbed by this plant:
5%
95%
0%
0%
1.
2.
3.
4.
Green and orange
Red and violets
Violet and green
Green and reds
0%
14%
86%
0%
0%
Based on the graph below, which color light
is least absorbed by plants for
photosynthesis
1. Red
2. Yellow
3. Green
4. Orange
5. Violet
What is this graph showing you??
pH
A scientist wants to study photosynthesis in a
newly discovered species. Which of these cell
structures should the scientist study?
100%
Vacuoles
Chloroplasts
Mitochondria
Ribosomes
0%
M
m
es
so
ib
o
ito
ch
la
s
hl
or
op
C
R
ts
s
ol
e
cu
0%
on
dr
ia
0%
Va
1.
2.
3.
4.
Muscle cells require more energy than do most other cells.
Which organelles would you expect to find
in greater abundance in muscle cells than in most other
cells?
95%
hl
or
op
la
s
ts
m
es
so
ib
o
ito
ch
M
R
ili
a
5%
0%
on
dr
ia
0%
C
Cilia
Mitochondria
Ribosomes
Chloroplasts
C
1.
2.
3.
4.
Which of these processes results in
carbon dioxide production?
77%
Osmosis
Respiration
Evaporation
Photosynthesis
18%
5%
he
s
is
tio
n
Ph
ot
os
yn
t
or
a
ap
Ev
R
es
sm
os
pi
ra
tio
n
is
0%
O
1.
2.
3.
4.
Some organisms that live in the intestines of cows
do not require oxygen to survive. Which of these
best describes the process by which these
organisms obtain energy?
100%
1. Osmosis
2. Mitosis
3. Cellular
respiration
4. Fermentation
0%
O
os
m
s
0%
is
M
si
ito
C
s
l
el
ar
ul
re
0%
n
tio
ri a
sp
Fe
rm
tio
ta
n
e
n
Let’s fill in this chart with the molecules
and then the energy transformations
_____________________
_________________________________
_________________________________
_____________________
Why do leaves change colors??
Carotene
Xanthophyll
Chlorophyll A
Chlorophyll B
These
chromatograms
show
chlorophyll b at
the bottom,
followed by
chlorophyll a,
xanthophylls,
and carotenes.