Cellular Respiration!!
Aerobic vs. Anaerobic Respiration in
Organisms
Introductory Activity: Exercise!!!
What happens when
exercise the same muscle(s)
for a long time without
giving them any rest?
Do you feel sore the day
after performing fun sports?
Why?
CHOOSE A VOLUNTEER FOR THIS
ACTIVITY!!
Graphing our exercise…
To calculate your heart rate:
count how many ‘beats’ in
20 seconds…. Using your
pulse from your wrist or
neck! Not your chest!
-- Practice it now and get
your resting heart rate; do it
twice for more accuracy.
-- Is it good or bad to have a
low resting heart rate?
Why?
Do some exercise… as much as you can
in about 1 minute’s time.
Oxygen Debt…
What do you notice about the
heart-rate immediately after
exercise, and then two minutes
later?
Why does the heart-rate not
immediately decrease once the
exercise has been completed?
Take a guess!
We’ll discuss the answer
shortly…
Cellular Respiration Part 1
1) ATP stands for _____________________.
It is the main energy molecule, and the perfect
energy storage ‘currency’ used by most organisms’
cells. The ATP molecule is composed of a sugar
molecule, __________________, which is attached
to a base, ____________________, and a string of
three ____________________ molecules, which can
be ________________ when energy is needed, or
___________________ when extra energy, from
sunlight (in plants) or from food, needs to be stored!
Colour-Code the ATP molecule and its
parts……
Cellular Respiration Part 1
2) An enzyme, _______________________,
triggers the release of a phosphate group
from ATP to create ADP, which stands for
Adenosine Di-Phosphate; lots of energy is
also released in the process!!
Further energy can be produced by releasing
another phosphate molecule, which forms
AMP.
AMP stands for: ______________________.
ADP
AMP
Cellular Respiration Part 1
When extra energy is available, the reverse
reaction occurs, and phosphate groups are
added back on.
AMP
ADP
ATP
Uses of ATP:
What is ATP used for in our body’s cells, and
particularly in our muscles? (see textbook p.226227)
• Cells need energy to do their jobs (e.x. muscle
cells, for contracting, relaxing, and doing
work!!)
• Homeostasis
Aerobic + Anaerobic Respiration
Overview!
3) PREDICT: Is all the energy
that comes from our food
used at one time? What
would happen without our
body’s ability to create and
utilize ATP when energy is
needed? Observe what
happens when food energy is
released all at once!
Aerobic + Anaerobic Respiration
Overview!
4) The first stage of cellular respiration is called
___________, and occurs WITHOUT ________
in the cytoplasm of cells. It is a VERY fast
process; in just a few milliseconds, __________
of ATP molecules can be produced!
a) Why is this significant to our lives??
Disadvantage of anaerobic
respiration?
4. b) What is a disadvantage to
the speed of the glycolysis
process?
• MUSCLE CRAMPS!! Why?
• Anaerobic respiration
happens much faster than
O2 can be delivered to our
cells, and the waste
products cause cramps!!
Glycolysis… more Latin root words!
5) Glycolysis comes from two greek
words; Glukus, meaning ____________,
and lusis meaning to loosen or release!
Input + Output of Anaerobic
Respiration in Humans
6) During glycolysis, 2 ATP molecules are used to
break down a single 6-Carbon glucose molecule
and re-form the bonds to produce TWO (2)
Pyruvic Acid molecules (each using 3 of the
Carbon atoms from glucose) and enough energy
to form FOUR (4) ATP molecules.
USE THIS INFORMATION TO COMPLETE THE
TABLE BELOW!!
Anaerobic Respiration input and
output in cellular respiration!!
Anaerobic Respiration
Input
Aanaerobic Respiration
Output
Net Output:
4x ADP
4x ATP
Two (2) ATP!
2x ATP to start the
process
2x ADP
2 NADH
1x Glucose
2x Pyruvic Acid
(a 6-carbon molecule) (a 3-carbon molecule)
2NAD+
2x Pyruvic Acid
2NADH
Anaerobic Respiration Info:
Anaerobic Respiration and Oxygen
Debt Lesson 2
1) Two molecules of pyruvic acid are produced
for every molecule of ____________________
that’s consumed during _________________.
Another important molecule…
2) Another important molecule for all steps of
cellular respiration is called NAD+, which stands for
_______________ ______ ________________.
The ‘+’ represents a missing electron from the NAD+
molecule. For every ONE molecule of glucose
broken down during glycolysis, TWO NAD+
molecules are oxidized (See Fig. 9-8, p. 263). An
NAD+ molecule gets back its missing electrons by
bonding with hydrogen, to become
_____________.
Important Aerobic Process
3) NADH is brought inside the mitochondria of
the cell, where they are used as part of the
aerobic process called the ________________
transport chain (E.T.C.), which requires
_________________ to operate! (Clue: what
does Aerobic mean?)
Without Oxygen, the NADH molecules are stuck!
Our cells have 99 problems, and
Oxygen is one of them.
4) Without Oxygen, the NADH molecules can’t
drop off their electrons at the E.T.C.! Because
glycolysis happens so quickly when we need ATP
(especially during exercise), soon there’s
nowhere for the NADH molecules to go with
their electrons… and no NAD+ for glycolysis!
Without ____________ molecules, glycolysis
can’t happen!!
A firm solution…
5) A process called ___________________
allows cells to recycle the extra electrons from
NADH, which regenerates NAD+ and allows
____________ production through __________
to continue!
A burning sensation…
5) In humans, the main waste product of this process
causes a burning sensation that damages the cells, and
limits how long it can be used for fueling glycolysis!
a) This type of fermentation is called
_____________________ _______________
fermentation!
Look at the overview for Glycolysis
5 b) How many times must this happen to power the
breakdown of a glucose molecule?
Waste products…
6)What happens to this ‘waste’
that our cells produce in times of
desperate need?
________________ is required to
help clear our cells of the lactic
acid that builds up, hence the
term “Oxygen Debt”!
Fitness Levels… and Tap Dancing!
7) This acidic waste product limits
how much ‘hard’ exercise we can
do to about 60-90 seconds...
Depending on your fitness.
Someone start a timer, and tap
your feet as many times as you
can, as fast as you can, WITHOUT
stopping…. Once you stop, take a
break, etc., you’re OUT! Who can
go the longest?
Activity Time!!
8) When doing intense exercise, glycolysis and lactic acid
fermentation provides enough ATP for ~ 90 seconds in the
average person.
a) How long did you last before you really felt the ‘burn’?
b) How long before you were unable to continue at an
‘extreme’ pace?
c) Despite a deep burning sensation, you probably weren’t
breathing heavily after this exercise (if you were, start
going to the gym!). Does this mean there was no ‘oxygen
debt’ acquired? Why (or why not?)
d) Why would you breathe much more heavily after, say, a
90 second sprint than an exercise like what we did?