1. Cellular Resp·raron
•How do living things release energy???
e Quick Rev·iew...
-Most energy used thru conversion of ATP molecules into ADP
molecules
-Thus cells must continually convert ADP molecules back into ATP
molecules
-This process is know n as ..........
CELLULAR RESPIRATION
2. Lesson Object'ves
• ame the three stages of cel.u.ar resoi-ation.
• Give an overvie1.M of gvco.vsis.
• xp!ain V•/hy gl/ col/ sis probablV evotveo oefore the other stages of
aerooic respiration
• Describe the st uctu·e of the mitochono rion ana its role in aerobic esp·
aron.
• L st the steos of tne K ·eos C/ C e, ano ioentif y its prooucts.
• rxp lain ho1.1v e.ecro transport results in man/ mo ecules of ATD.
• Descr"be hovv chem·osmor c gradients in mitochono ria store ene"g}t to
proouce ATD.
• State the possio e numbe of ATP molecules that can result f '"om ae
- ooic respiration.
• Define f ermeritation.
• Describe lac tic acid f e"r-nentation ano alcoholic fermentation.
• Compare the aavantages of ae obic anc anae obic -esoiration.
• Compare cellular resp- '"ation to ohotosvthesis
3. Breathing versus Cellular Respiration
•Breathing: physical process that allows animals and
humans to come into co ntact with gases in the air
•Cellular respiration: chemical process that releases
energy from organic compounds (food}, gradually
converting it into energy that is stored in ATP
molecules
4. Correlation between a campfire and Cellular
Respiration
•Analyzing a campfire can clarify your understanding of
cellular respiration.
- A campfire breaks chemical bonds in wood, releasing stored energy
as light and heat
- Cellula r respiration breaks chemical bonds in glucose, releasing
stored energy and transferring some to 38 ATP; some energy is lost
as heat.
5. Chemical Pathways
• Food is the raw mater"al that p ovides
the energy for your body to funcr on
• Cel s use food to synthesize new
molecules to carry out their life
processes
6. • Cells do not BURNglucose,they slow y release energy from it
and other food compounds through several pathways
(processes)
lst pathway [2J glycolysis releases only a small amount of energy
(2
net ATP)
•If oxygen present, it will lead to two other pathways that release a lot of
energy: Krebs cycle & Elec ron Transport Chain
•If oxygen absent glycolysis is followed by a different pathway: A lcoholic
Fermentation or Lactic Acid Fermentation
Dl'IA
ou er membrane
Inner membr& I!
7. d
$
Substrate .
lev1
e
phasphary1
1
auon
Glucose (6 carbon:sJ
CfiH120f.
. - Electrons carried
v
l
ia NADH and
FADHJ:
ELECTRON
TRANSPORT
CHAIN ARD
OXIDA VE
PHOSPHORYL
ATION
Mitochoindrion
01
xidalliiV1 .
pho.sphorylanon
$
Subs.tra1e..1ev
e1
p1
hosp ory
a1o·n
StageI•.
2 A
T Glymlysis
, ; in lytoplasm
2 ADH . - - - - J
4A: p
(l net)
Pyruvate
[l carbons)
Pyruvate
(3 carbons)
2 A H .·
e- - - V·- 2 CO1
8 A H .....- Krebs
2 FADH ....,.._
2
4 00
2
i ; ; ; ; ; ; ; ; ; : = l A
P
Stage II.
cycle
El
1
1
!
1
1
:trot'li transport
Pnosp.korylat ion
32A
TP Stagi!! HI.
Electrons
carried
vlla. NIADH
GlYCOLYS S
Glucose Pyruvale
Cytoso
8. ll hree co
b1
ned mak up ellular e pira 1 n l ol 1 Kreb
ycle lee ran ran
par
Process t at e
ea e re e ce o
ha1n
dio id
l 2
EJ.ECTAOtil
1RAN$PQRT
! CllUllAND
DXIDATlllE
PHOtiPHORYLATION
G l"tCOLYSIS
E ch of
th
a
1
l bl in - - - n
10. Glyco ysis
•Process takes place in the cytoso of t e cytop asm
outside of mitochondria ; coverts g ucose with the elp
of 2 ATP molecules and eventually releases 4 ATP
molecules; for a net gain of 2 ATP molecules.
• Cytosol -the flu id (and suspended molecules of
salts, sugars. a.mino acids. enzymes, etc.)
around the organe Ues
' Cytoplasm - the cytosol PLUS the organelles
suspended wrth in it (i.e., everyth Ing EXCEPT the
nucleus)
Gytosol + Organelles
Call Plasma miembran@ + Cytoplasm + Nuc laus.
v '
ICyto.sol+ Organelles
12. ATP &
NADH
produc ion
in Glyco
ysis
2 NADH
& 2 H
+
produced
· mo e I
ot GA.L [ 3 bonl
Ste 1: brea s 1 molecule of glucose in
hal p oducing 2 · · olec ules of py uvic
acid (a 3-ca bo · compound)
Ste 2: 2 · AD+ ;electron carrier
accepts 4 high-energy elec tro s
transfers them to 2 AD molec ules
and 2 thus
passi g the e e gy sto ed i · t e
glucose
2 NA.DH
Step 3. 4 ADP ad · ed producing 4
ATP
Ste 4: 2 remaining
pyruvic acids enter Kre s Cycle i ·
presence of oxygen; I
no oxygen another pathway is followed
AD+ (nicotina ide adenine . inucleotide)
2 ATP
used
up
becom
e 2
ADP
4 ATP
produced Net
gain =·
2 ATP
13. e Glycolysis is a fast
process
e Cells produce thousands of ATP molecules in a few milliseconds
e Glycolysis alone DOES NOT require oxygen
- It can supply chemical energy to c,ells when oxygen is NOT ava i la ble
How ever if a cell gener ates large amounts of ATP from glycolysis it
can run int o problems
a.the cell's available NAO. molecules become filled up with
electrons
b.glycolysis shuts down! cannot proceed without available NAO.
molecules
c.ATP production stops
14. AnaerobictoAerobicR
esoiration
•Glycolysis evolved before the other stages of
cellular respiration; other stages need oxygen
•No oxygen in Eart h's atmosphere when life fir st
evolved about 3.5 to 4 b.y.a.
•Wit hout oxygen !Xi anaerobic respiration
•2 or 3 billion years ago, oxygen was gradually added
to the atmosphere by early photosynthetic bacteria;
period the "oxygen catastrophe" [gjaerobic
organisms
15. Let's look at the
pathway that follows gycolysis
with the
presence of oxygen•....
aerobic respiration
17. •End of glycolysi s[gl 90°/o of chemical energy from
glucose still unused, locked in high energy
electrons of pyruvic acid
•Ext racted by world's most powerful electron
recepto r
•Krebs and Electron Transport require oxygen thus
they
are aerobicprocesses oxv N
AEROBIC RESPIRATION:
The Krebs Cycle and Electron Transport
20. •Carbon dioxide is exhaled (waste product)
e ATP1
can be used fo r cellular activities
•High-energy electrons (stored in NADH & FAD H2)
can be used to make huge amounts of ATP in the
presence of oxygen
Uses for the products of the Krebs Cycle
21. low p
Int rmem brane 11
space
H
.. on ncii -
in1• rmam b ran•
a _
c
lli't"
ain
Mit0ich1
ondrial Electro1
n Transpia- Chain
for
w r
• Eachtime2
dtotran Ort
onsaao
• on buidup n
n gatiVey charged
• ctrochmcalgrad
syntha
converts
•14..
1
matMx
hi!;lh
law Hconcentra
22.
23. Let's look at the
pathway that follows
gycolysis without the
presence of oxygen•....
anaerobic respiration
24. Anaerobic Respirat'on: Fermentation
This occurs after g/yco/ysis when oxygen absent thus anaerobic
process
•Fermentation releases energy from food molecules in
absence of oxygen
-In this process cells convert NAOH to NAO. by pass·ng high-energy
electrons back to pyruvic acid
-Now glycolysis has NAO. and can continue producing ATP
-There are 2 types of fermentation:
• A lcoholic fermentation
• Lactic acid fermentation
25. •Anaerobic and aerobic respiration share the glycolysis
pathway. If oxygen is absent. fermentation may take place.
producing lactic acid or ethyl alcohol and carbon dioxide.
Products of ferme ntation still contain chemical energy, and
are used wide ly to make foods and fuels.
26. a
n
h r
n i r 1
n
(a) !
Lactic ac·'d f'e1
rmentat·
,
on occurs ·n human1
s.
2 ATP
o-
1
C=O
I
C=O
I
CH3
2 P yruvat-e
2 NAD
or
-
1
C== O
I
H -C-OH
I
CH
- 3
2 Lactate I 2 Latt c Ar d
ID l l i l l l l - . 1 - .
No interm1
ediarte·
1
pyruvarte,accep,
ts
erectr,
cns from NlADH
27. e e
0
ac
d
0 0 o ac ca d· actc
e
o actc
(a) Lac.tic acid f'e:
rmerdation ,
occurs in humans.
2ATP
o-
1
C= O
I
C= O
I
CH3
2 NADH 2 Pyruvarle
2 N
o-
1
C==O·
I
H-C-OH
CH,a
I
N,o intem ed
i
aite·
;
pyruv,
arte accepts
e ectrons,from1NlAD:
H
28. Running! swimmin g, or riding a bike as fast as you can = large
muscles in your legs and arms that quick ly run out of oxygen
...musc les begin to rapidly produce ATP by lactic acid
fermentation.
The buildup of lactic acid fermentation causes a painful
burning sensation making your
muscles feel sore...
How do you stop it?????
NEED TO INTAKE OXYGEN
29. Energy and E
xercise
e Initially body uses ATP w hich is already available in musc
les
e Then new ATP made by Lactic Acid Fermentation and
Cellular Respiration
e Eventually energy supp ly runs out A. Quick Energy
l. ATP in musc les only lasts a few seconds
2. ATP f rom lactic acid fermentation lasts about 90 seconds
- this then creates a by-product (lact ic acid) w hich the body
must get rid of, the body
releases it by panting heavily (intake of oxygen)
30. B. Long-Term Energy
- exercise lasting longer than 90 second.s ut ilize.s
cellular respiration to generate a continuous supply of ATP
- cellular re.spiration releases energy slower than
fermentation, thus athletes can pace themselves
- body stores energy in muscles and tissues in the
form of glycogen (carbohydrate)
-- .st ores of glycogen usually lasts for 15-20 minutes of activity
then the body starts to break down
other molecules like fat for energy
H01
W LONG DO ·you NEED TO ACTIVE BEFOR E You START TO
BURN
FAT?????
17-22 minutes
