Topic 3.3
Nutrition and Energy Systems
Structures of an animal cell and mitochondria
Structures of an Animal Cell
Crash course ATP & Respiration 13min
• Rough Endoplasmic Reticulum (ER): transport system
• Ribosomes: assemble proteins
• Golgi Apparatus: process, package & deliver proteins,
lipids.
• Lysosomes: form from golgi, contain enzymes for
digestion.
• Mitochondria: produce ATP.
• Nucleus: controls all cell functions.
Structures of a mitochondria
• Outer membrane: protection & allow certain
molecules in.
• Inner membrane: location of energy
production.
• Cristae: the folds of the inner membrane,
increase surface area.
• Matrix: space enclosed by inner membrane.
Complete the production of ATP.
Cellular respiration
• The controlled release of energy in the form of
ATP from organic compounds in cells.
Role of ATP in Muscle Contraction
• Breakdown of ATP to ADP releasing a
phosphate molecule, which provides energy
for muscle contraction.
1
ATP
2
3
ATP already in skeletal muscle cell
• Stored ATP in muscles cells is used for a few
seconds of energy
ATP –CP system
• Creatine phosphate (a high energy molecule)
is broken down to provide a phosphate
molecule for the re-synthesis of ATP that has
been utilized during the initial stages of
exercise.
Lactic Acid System (Anaerobic Glycolysis)
• Breakdown of glucose to pyruvate without the
use of oxygen. Pyruvate is then converted
into lactic acid which limits the amount of ATP
produced (2 ATP)
Aerobic (Glycolysis)System
• In the presence of oxygen pyruvate is processed by the
Krebs cycle which liberates electrons that pass through
the electron transport chain
• Fats are also broken down and can yield more ATP
than carbohydrates. Protein is used in extreme cases.
Review Terms
• Glycogenolysis: breakdown of glycogen
(stored sugar in liver/ skel. muscle) to glucose.
• Glycolysis: breaks down glucose to pyruvic
acid.
glycogenolysis
glycolysis
Glucose, Glycerol
Anaerobic
Glycolysis occurs in the cytoplasm of the cell. In the presence of oxygen
pyruvate is transferred into the interior of the mitochondria where it is
processed in the Citric Acid (Krebs) Cycle to produce some ATP, and many
High Energy Hydrogen bonds. These hydrogen bonds are transported into
the inter-membranous space of the mitochondria where the Electron
Transport Chain produces ATP by utilizing the enzyme ATPase.
System Contributions
• Discuss the three energy systems relative contribution during
exercise.
• Consider such factors as fuel source, duration, intensity & amount
of ATP production.
• All activity, endurance or not follow the same order. ATP stores are used first,
followed by CP, Anaerobic and then Aerobic. Athletes can use the anaerobic and
aerobic systems alternately. For example, running up hill or accelerating during
a long distance race will cause a runner to switch from aerobic to anaerobic to
do so.
• Evaluate the relative contribution of the three
energy systems during different types of
exercise.
Exercise
Duration
100m sprint
10 sec.
Marathon
3hrs 45min
100m swim
64 sec
Gymnastics vault
2 sec.
400m run
60 sec.
1500m run
5min 9sec.
Basketball shot
1 sec.
Predominant
Energy System
Oxygen Debt & Recovery
• Oxygen deficit: the difference between the
oxygen the body requires and what it actually
manages to take in.
• Oxygen debt is know as excess post-exercise
oxygen consumption (EPOC)’ and is the extra
oxygen your body has to “pay back”.
Oxygen Deficit: diff. between the amt. of O2 consumed during
exercise and the amt. that would have been consumed if
aerobic resp. occurred immediately.
*this reflects the amt. of
energy supplied to
muscles by the
anaerobic systems.
*trained athletes have a
smaller O2 deficit.
Oxygen Debt or (EPOC) excess post-exercise oxygen
consumption
*represents the amt.
of O2 consumed in
recovery after
exercise that is
above the resting
level.