Cellular Respiration
How do we ‘get’ our energy?
Photosynthesis Review
 Photosynthesis is when PLANTS absorb
SUNLIGHT, CO2 and H2O and turn it into
C6H12O6 and O2
Photosynthesis Review
 It happens in the CHLOROPLAST, with
the help of the CHLOROPHYLL
Photosynthesis Review
 The REACTANTS are CARBON DIOXIDE,
WATER and SUNLIGHT.
 These
things come BEFORE the arrow
 The PRODUCTS are GLUCOSE (SUGAR)
and OXYGEN GAS
 These
things come AFTER the arrow
Cellular Respiration
 Plants are PRODUCERS – because they can
make their own food by photosynthesis.
 We (humans) are CONSUMERS – we CANNOT
make our own food through photosynthesis.

We must EAT food in order to get our energy!
 Does FOOD = ENERGY?
NO!!
 Food = Food
 ATP = Energy
 We must turn our food into ATP by the process
called CELLULAR RESPIRATION!!
Cellular Respiration
 It happens in the MITOCHONDRIA
 It is the OPPOSITE of photosynthesis.
 Cell Respiration is the OPPOSITE of
Photosynthesis
Cellular Respiration
 Cellular Respiration takes GLUCOSE and
OXYGEN and turns it into ATP, CARBON
DIOXIDE and WATER
 The PRODUCTS of photosynthesis are
the REACTANTS for cell respiration
ATP
Gotta get that ATP - Biology Song – YouTube
 ATP stands for Adenosine Triphosphate
 The energy in ATP is stored in the
BONDS between the phosphates
 When the bond is broken, ENERGY is
RELEASED
1. The REACTANTS of respiration are
GLUCOSE and OXYGEN. The sugar
(glucose) is obtained from ingestion
(EATING) of food. The oxygen is
obtained from the AIR.
2. The PRODUCTS of respiration are
ATP, WATER and CARBON DIOXIDE.
The water and carbon dioxide are
released into the environment as
WASTE. ATP is kept in the cell for use
as ENERGY.
Do plants need to do Cell Respiration?
 YES!!! ALL living things must do cell
respiration!
 Photosynthesis provides no DIRECT
source of energy for the cell. The plant
cell must convert the sugar made during
photosynthesis to another form of
energy: ATP
Two Types
There are 2 types of cellular respiration…
the kind we’ve been discussing is
AEROBIC respiration because it
requires OXYGEN!!
Cellular Respiration
 Recall that Cellular Respiration
REQUIRES OXYGEN as one of its
reactants
 But what happens when ATP is needed
and there is NO OXYGEN available?
 Do you DIE?!?
Anaerobic Respiration
 Aerobic – “with oxygen”
AIRobic
 Anaerobic – “without oxygen”
 Anaerobic respiration happens when there
is no oxygen available.
 Does NOT make much ATP but it does
happen VERY FAST!!
 It is NOT the method we want to use…but it
will keep us alive
 Two types of anaerobic respiration:


Alcoholic fermentation
Lactic Acid fermentation
Aerobic Respiration
 AEROBIC Respiration
uses oxygen and
produces a LOT of
ATP

36 ATP for every glucose
molecule
 ANAEROBIC
Respiration does not
use oxygen and only
produces a LITTLE
ATP

2 ATP for every glucose
molecule
Types of Anaerobic Respiration
 There are 2 types of ANAEROBIC
respiration
 The type that is done depends on the type
of organism doing the respiration
 Alcoholic
fermentation – yeasts and other
microorganisms
Produces
alcohol and CO2
 Lactic
Acid fermentation – animals, like
humans
Produces
lactic acid and CO2
Alcoholic fermentation
 Done
by yeast and other microorganisms
 Produces alcohol and CO2 as waste products
 Bread
is made this way
Bread Making Video
http://www.youtube.com/watch?v=gYXjURcBk98
Alcohol…Harmful or Not?!?
YOU decide!!
 The yeast are
using the
sugar to make
ATP through
ANAEROBIC
respiration
 The balloon
fills up with
CO2, which is
a waste
product
The holes in Bread
are caused by pockets
of CO2, as a result of
anaerobic respiration
Lactic Acid fermentation
■ Done by animals, like humans
■Produces lactic acid and CO2 as waste
products
▫Lactic acid builds up in the muscles and causes pain
You’ve heard the saying…
“Feel the Burn!!” The burn is
caused by the acid building
up in your muscles.
Ouch