Transcript Unit 2 part 3 Cellular Respiration

Bellringer
• What is the name of the
molecule that living things
use for energy?
1
UNIT 2 PART 3: CELLULAR
RESPIRATION
• Energy is the ability to do work.
• All living things need energy, and they get it
from food. Carbs are the main source.
• Some energy is released as heat to
maintain body temp.
• The rest is stored in chemical form.
• The reaction takes place in many small
steps so energy is not lost.
2
• This energy
releasing process
is called
CELLULAR
RESPIRATION.
• As the chemical
bonds in food are
broken, energy is
released.
• The energy
released is used to
change ADP into
3
ATP.
ATP – the energy molecule
~
~
High energy
bonds where
energy is
stored
ADP has only 2 phosphate groups. During
cellular respiration the energy released by
the breakdown of food is used to attach
another P group to ADP making it ATP. 4
When the last P is removed from ATP, the
energy is transferred to another molecule to
do work like cell growth, repair, or transport.
5
Cellular respiration uses the simplest form of
carbs obtained from digestion - glucose
One molecule of glucose
(C6H12O6,), an organic
molecule, can make 38 ATP
molecules (energy storage in
the cell)
Cellular respiration can be written as:
C6H12O6 + 6O2  6CO2 + 6H2O + ENERGY
(ATP)
6
There are two types of respiration
• Anaerobic
– Does not use
oxygen
– Food is not broken
down completely
– Little energy is
released (4 ATPs)
– Alcohol or lactic
acid are wastes
(Fermentation)
– Occurs in
cytoplasm
• Aerobic
– Uses oxygen
– Food is broken down
completely
– A lot of energy is
released (38 ATPs)
– Carbon dioxide and
water are wastes
– Occurs in
mitochondria
7
OVERVIEW OF CELLULAR RESPIRATION
ANAEROBIC
RESPIRATION
cytoplasm Net total: 2 ATP
2 ATPs
Alcoholic
fermentation
(yeast)
2 ethyl
alcohol
+ 2 CO2
Lactic acid
fermentation
(bacteria)
2
Lactic
acid
4 ATPs
glucose
glycolysis
2
pyruvic
acid
mitochondrion
AEROBIC
RESPIRATION
Net total: 36 ATP
A
c
e
t
y
l
C
o
A
6 CO2 +
Krebs
cycle
Electron
6 H2 O +
Transport
Chain
34 ATP
C6H12O6 + 6O2  6CO2 + 6H2O + 36 ATP8
MUSCLE FATIGUE
• Muscle cells use aerobic respiration.
• During prolonged periods of exercise
muscles sometimes don’t get enough
oxygen so they use anaerobic respiration.
• This produces lactic acid which can build
up in the muscles making them sore.
• Need to rest to recover.
9
Anaerobic Respiration
Aerobic Respiration
in cytoplasm
in mitochondria
2 ATP
2 ____
Word Bank: Pyruvic acid, H2O,
CO2, CO2, Lactic Acid, Alcohol,
ATP, ATP, ADP, Glucose, O2
1 _______
4 ADP
34 ADP
4 ____
34 ____
6 ________ &
2 ______
_____
Yeast
Bacteria
2 ________ &
2 _______
2 __________
_______
6 ________
10