ATP
and
energy release
Higher Human Biology
Lesson Aims
• To compare aerobic and anaerobic
respiration
• To learn about structure and function of
ATP
• To learn about the three stages of
respiration
Metabolism
• Metabolism - all chemical reactions that
occur in cells
• Catabolism – produces energy when bonds
between atoms in our food are broken
• Anabolism – requires energy to make new
bonds building up molecules
Aerobic Respiration
• Organisms break down organic materials
through the process of aerobic cellular
respiration.
• The goal of this process is to break down
organic material and harness the released
energy in the form of ATP, the universal
currency of biological energy.
Anaerobic Respiration
• A few organisms can live without oxygen
(anaerobically). These organisms are
capable of metabolizing organic material,
but their ATP yield is much lower than that
found in aerobic respiration.
ATP and ADP
Adenosine
triphosphate
Adenosine
diphosphate
Respiration
3 stages:
• Glycolysis
• Kreb’s cycle
• Cytochrome system
ATP TOTAL
GLUCOSE
C6H12O6
GLYCOLYSIS
= 2
CYTOCHROME SYSTEM = 36
TOTAL
2 ATP
= 38
PYRUVIC
ACID
CYTOPLASM
GLYCOLYSIS
OCCURS HERE
MITOCHONDRION
ACETYLCoA
H2O
AEROBIC RESPIRATION
OCCURS HERE
O2
KREBS
CYCLE
CO2
HYDROGEN
CYTOCHROME
SYSTEM
36 ATP
Glycolysis
•
•
•
•
•
•
Anaerobic
Takes place in cytoplasm
Breakdown of glucose (6C)
Produces 2 molecules of pyruvic acid (3C)
Net gain of 2 ATP
Hydrogen released is transferred to Cytochrome
system by NAD
• If no oxygen present, pyruvic acid converted to
lactic acid
Glycolysis
Mitochondrion
Kreb’s Cycle
•
•
•
•
•
•
•
•
Aerobic
Takes place in matrix of mitchondria
Also called TCA or Citric acid cycle
Pyruvic acid diffuses into matrix and is broken down
into Acetyl CoA (2C)
Acetyl CoA binds with 4C molecule to give citric acid
Citric acid broken down into 4C molecule by series of
enzyme-controlled reactions
Produces CO2
Hydrogen released is transferred to Cytochrome system
by NAD
Kreb’s Cycle
Cytochrome System
•
•
•
•
•
Takes place on cristae of mitochondria
Also called electron transfer chain
Hydrogen passed along chain
36 ATP produced
Oxygen is final hydrogen acceptor
releasing water
Cytochrome System
The Facts You Need To Know
• page 2-3
• from “respiration occurs in….”
• to “if oxygen is available…”