Download NOTES: 9.1-9.2 - Cellular Respiration

NOTES: 9.1-9.2 - Cellular Respiration
Vocabulary:
-Glycolysis
-Kreb’s Cycle
-Pyruvic acid
-electron transport chain
-ATP
-glucose
-Aerobic
-Anaerobic
Chemical Energy & Food
● Organisms get the energy they need from
.
● Energy stored in food is expressed in units of
.
● 1 calorie = the amt. of energy needed to raise the temp. of 1 g of H2O by 1°C.
● Different foods are capable of storing different amounts of energy:
● 1 g glucose:
(3.811 kcal)
●1 g beef fat:
(8.893 kcal)
How is the energy in sugar (glucose) molecules released so it can be used by the cells of an organism?
● Cellular Respiration occurs in both plant & animal cells
-WHERE?
-
and
(the
of the Cell!!)
Cellular Respiration….a controlled process
● Food (glucose), like fuel, is "burned" by our cells for energy
-however, if it's burned all at once, too much energy is released
● therefore, the reaction is broken down into many small steps controlled by
-Cells gradually release the energy from glucose and other compounds
● the energy is transferred to the
amounts to be used by the cell
of
● energy is
which stores and releases the energy in usable
between phosphate groups
CELLULAR RESPIRATION:
● Process that releases
presence of
by breaking down food molecules in the
● Occurs in both
and
Cellular Respiration occurs in 3 stages:
1)
2)
3)
GLYCOLYSIS (glyco
, lysis =
)
● Process occurs in the
● Breaks glucose down from 6-carbon compound into two 3-carbon compounds (called
or
)
Equation for glycolysis: (write equation on line below)
● Glycolysis can occur if oxygen is present (
) or absent (
)
-Glycolysis is ALWAYS the first step in breaking down glucose
● If oxygen IS present, then cells proceed with
● If oxygen is NOT present, then cells will carry out
Cellular Respiration can be broken down into 3 processes:
1) GLYCOLYSIS: glucose is broken into
;
;
electrons from glucose passed to
2) KREBS CYCLE: pyruvate broken down into
) & electrons are passed to NAD+ 
(
NADH;
3) ELECTRON TRANSPORT CHAIN: high energy elec. from glycolysis & Krebs (NADH) are used to

;
Overall Equation(s) for RESPIRATION:
Glucose
+

Oxygen
Carbon Dioxide
+

+
+
Look Familiar????
Krebs Cycle & E.T.C.
● Occur in the
of a cell
● Only if
● Uses the pyruvic acid from glycolysis to produce
● Products:
-34 ATP per molecule of glucose
-carbon dioxide, CO2
-water, H2O
So how does this happen?
(
)
,
, and
Water
● The KREBS CYCLE breaks the bonds of pyruvate; high-energy electrons are
;
waste product CO2 produced; 2 ATPs produced.
● ELECTRON TRANSPORT CHAIN: uses high-energy electrons from NADH (&FADH2) from gly. & Krebs to

convert
● The NADH and FADH2 (from glycolysis & Krebs cycle) carry energy to the electron transport chain to make more
ATP (this requires
; oxygen acts as the final electron acceptor in the chain)
Write Equation for RESPIRATION on the line below:
Summary of Cellular Respiration
Glycolysis
“break sugar”
Krebs Cycle & E.T.C.
Location in the cell:
It starts with:
It ends with:
2 (C3H6O3) pyruvic acid
Is Oxygen required?
# of ATP’s Produced
GRAND TOTAL =
ATP
• 2 are produced in Glycolysis, 2 in Krebs Cycle, and 32 in Elec. Trans. Chain
-18 times more ATP are produced in the presence of Oxygen!!
How efficient is this?
• The 36 ATP molecules the cell makes per 1 glucose represents about 36% of the total energy in glucose
• Even though it doesn’t seem like much, this is more efficient than your car’s gas burning engine
• What happens to the remaining 64%???
-