Unit 4 Energy systems - Nutrition and energy systems Flashcards
processes
- glycogenisis: glucose to glycogen
- glycogenolysis: glycogen to glucose
- Gluconeogenesis: lactate to glucose
- Glycolysis:
(aerobic) glucose to CO2 + H2O
(anaerobic) glucose to lactate
structure of animal cell (6)
- Ribosomes: Protein synthesis location
- Rough Endoplasmic Reticulum (RER): Folds and packages proteins and sends them to the Golgi Apparatus
- Lysosomes: Digestive system of cell
- Golgi Apparatus: sorting, storing, modification and export of secretory products
- Mitochondria: Aerobic Respiration location
- Nucleus: Stores genetic material (DNA); nucleolus is site of ribosome assembly
structure of mitochondria - 4
- Cristae: the inner membrane is arranged into folds (cristae) that increase the SA:Vol ratio (more available surface)
- Inner Matrix: central cavity that contains appropriate enzymes and a suitable pH for the Krebs cycle to occur
- Inner Membrane: contains the electron transport chain and ATP synthase (used for oxidative phosphorylation)
- Smooth Outer Membrane: the outer membrane contains transport proteins that enable the shuttling of pyruvate from the cytosol
the process the body uses to generate energy: (process, def, types)
- Cellular Respiration
The controlled release of energy in the form of ATP from organic compounds in cells.
Types
1. Phosphocreatine System
8-10 seconds
100 m runner
2. Anaerobic Glycolysis
1-2 mins
400 m swimmer
3. Aerobic Glycolysis
unlimited time
marathon cyclist
form and function of ATP
form: be able to draw!!!
adenine + ribose + high energy bond
function:
* the energy currency of the cell by releasing energy when hydrolysed to ADP
* Transfer the released phosphate group to other organic molecules, rendering them less stable and more reactive
phosphocreating system overview - 3, resynthesis ATP - 4, location - 1
- Creatine is an organic molecule found most commonly in the brain and muscles.
- Creatine Phosphate is creatine with a phosphate group attached to it.
- One of its uses is to recycle ADP+P → ATP
How does creatine phosphate resynthesis ATP?:
Creatine phosphate + ADP + H+ ⇔ Creatine + ATP
* Creatine Phosphate donates a phosphate molecule to ADP to create ATP.
* At rest the reaction goes the other way, ATP donates a phosphate to creatine to regenerate Creatine phosphate.
* Short duration because muscles can only hold so much Creatine phosphate. It gets used up
location:
CP is released from mitochondria and generates ATP in myofibrils
phosphorylation:
Phosphorylation is the process of adding a phosphate atom to a molecule.
Phosphorylated molecules are less stable (more reactive).
aerobic glycolysis general process, steps, equation
Glucose + Oxygen → CO2 + H2O + ATP
* general process: In the presence of oxygen, pyruvate is processed by the Krebs cycle, which liberates electrons that are passed through the electron transport chain producing energy (ATP).
* makes 38 total ATP per glucose molecule
Steps:
1. Glycolysis
2. Link Reaction
3. Krebs Cycle
4. Electron Transport Chain
glycolysis step of aerobic/anaerobic glycolysis - 8
- Glucose (6 carbons) → 2 pyruvate molecules (3 carbons)
- Occurs in the cytoplasm of cells / muscle sarcoplasm
1. Glucose is phosphorylated to destabilize it
–> This costs 2 ATP
2. Glucose splits into two molecules
3, Other reactions occur resulting in 2 pyruvates
–> Produces 4 ATP
= Net Gain of 2 ATP / glucose
link reaction of aerobic glycolysis
PROCEED ONLY WITH OXYGEN PRESENT IN SUFFICIENT QUANTITIES
* 2 Pyruvate → 2 acetyl CoA
* Moves the pyruvate from the cytoplasm to the mitochondria.
* Produces CO2 as a waste product.
krebs cycle step in aerobic glycolysis
In the presence of oxygen; carbohydrates, lipids or proteins, can enter the mitochondria to perform the krebs cycle followed by electron transport chain.
The oxidation of acetyl groups is coupled to the reduction of hydrogen carriers, releasing carbon dioxide.
Cycles happens 2x per glucose molecule as there are 2 acetyl CoA
Matrix of mitochondria
Produces:
* 2 ATP
* Molecules for ETC
* CO2
* Hydrogen ions
electron transport chain (ETC)
- Located on the inner mitochondrial membrane
–> The inner membrane is arranged into folds (cristae), which increases the surface area available for the transport chain - The molecules from the Krebs cycle help move electrons through a series of Hydrogen ion (proton) pumps resulting in a large number of ATP
–> Makes 34 ATP
–> Makes Water
Fatty Acid Beta Oxidation
- Fats are also broken down by beta-oxidation that liberates a greater number of electrons, thus more ATP.
- Fatty acids are able to go into the krebs cycle and then the ETC to generate ATP.
Process of production of ATP from glucose & fatty acids by the fatty acid beta oxidation:
1. Beta oxidation catabolizes fatty acids into Acetyl CoA if oxygen is present.
2. Acetyl-coA and oxaloacetic acid combine to form citric acid.
3. Citric Acid is able to enter the Krebs Cycle.
4. Electrons are released from the Krebs cycle and beta oxidation into the electron transport chain
5. Produces triple the amount of energy than glucose 100–150 ATP
6. Waste products are CO2 and water
anaerobic glycolysis
(glucose to lactate)
AKA lactic acid system
* The body will use this system when there is not enough oxygen present to use aerobic pathways to generate ATP.
–> Aerobic has not started yet
–> Exercise intensity needs more ATP than the aerobic system can provide.
either to slow (lots of steps) or can’t get enough oxygen in quick enough.
* Process is quick to generate ADP → ATP
* Makes 2 ATP only (in glycolysis)
* Occurs in cytoplasm only
Process:
* Glucose → Lactic Acid + ATP
* Only carbohydrates can use this pathway
Steps:
1. Glycolysis (same as aerobic)
2. Lactic Acid Fermentation
oxygen deficit
- Deficit (O2) at start of exercise met by the CP and anaerobic systems
- oxygen demand is greater than oxygen supply
- difference between the oxygen required for a given rate of work and the oxygen actually consumed
