Energy systems

Question 1

Carbohydrates

Answer 1

Main energy source. Used immediately through glucose or stored for future use.
Rice, bread, pasta, cereals, potatoes.

Question 2

Proteins

Answer 2

Muscle growth and repair. Structure, reactions and transport. 16 % of the body is made up of proteins. Hemoglobin, muscle tissue, chemical reactions take place because of proteins, etc. Last resort energy source.
Pulses, meats, eggs, fish, dairy, nuts.

Question 3

Fats

Answer 3

Low intensity exercise. Secondary energy source if carbs are low. Protects vital organs. Thermal insulation.
Meats, eggs, avocados, nuts, dairy, oils.

Question 4

Water

Answer 4

Prevents dehydration. Allow biochemical reactions to occur. Excretion. Lubrication in joints. Thermoregulation.

Question 5

Vitamins

Answer 5

Promote bone health, strengthen the immune system and enable energy release.
Fruits, vegetables, fish.

Question 6

Minerals

Answer 6

Aid the absorption of vitamins. Their job is to allow vitamins to do their job. Strengthen bones and teeth, promote blood oxygen transport, aid muscle function.
Fruits, vegetables, fish.

Question 7

Fibre

Answer 7

Carb. Provide roughage, enabling us to go to the bathroom. Bulks food and prevents hunger, slows down sugar spikes (prolonging the release of energy).
Fruit and vegetables, grain, cereal.

Question 8

Chemical composition of glucose molecule

Answer 8

Carbohydrate: carbon + hydration. Carbon and water.
Glucose molecule: C H2 O = 6 carbon, 12 hydrogen, 6 oxygen. C6 H12 O6. Ratio 1:2:1.
There are different types of glucose molecules, so all you have to do is count that there are 6 carbon, 12 hydrogen and 6 oxygen.
If you can see a hydrogen, you know it’s a protein. If you see a long carbon chain, then you know it’s gonna be fat.
How glucose molecules can combine to form disaccharides and polysaccharides.
DISACCHARIDE: Two glucose molecules. They form together and combine through a condensation reaction. A water molecule is lost through the equation. It is formed by a glycosidic bond. We lose the water molecule and it leaves one oxygen molecule from one of the glucose molecules. This is attached to the other one, to the carbon. This reaction combines them together to form a disaccharide. OH (one molecule) HO (other molecule). Bye 2 H and one O. The other O and a C from the molecule left with nothing joined. 2 glucose molecules together. This can happen more than once. It can happen like 6000 times and have them stored as glycogen in our liver and muscles.
POLYSACCHARIDE: More than 9 times.
Reversed: Stored glucose, glycogen, as energy and is broken down to release glucose molecules as and when we need it.

Question 9

Composition of a molecule of triaglycerol and saturated and unsaturated fats

Answer 9

Glycerol + three fatty acids.
SATURATED: Full, dense. Full of hydrogen.
Animal sources: Meat, poultry, full fat dairy, tropical oils, coconut oils.
UNSATURATED: Two double bonds. Instead of attaching to hydrogen on the other side, they are actually attached to each carbon within the chain. Every carbon within the chain has 2 hydrogen. In the unsaturated, they have two double bonds. Meaning 4 carbons that have one hydrogen each and are attached to each other. The more double bonds, the more unsaturated they are. So a monounsaturated: one double bond. Polyunsaturated: two or more double bonds.
Plant based: Olive oil, olives, avocado, peanuts, cashew nuts, canola oil, seeds, sunflower seeds, rapeseed.
Omega-3 fatty acids are in fish, fishy oils.

Question 10

Chemical composition of a protein molecule and the difference between essential and non essential amino acids

Answer 10

20 amino acids in the body and are chemically different. CARBON, HYDROGEN, OXYGEN and NITROGEN are in all amino acids.
ESSENTIAL: Cannot be synthesized by the body. Must be obtained through diet. 9 essential amino acids.
NON ESSENTIAL: Can be synthesized by the human body, we do not need to obtain them through diet. 11 non essential amino acids.

Question 11

Recommendations for a balanced diet in different countries

Answer 11

45-55 % carbs. Should dominate diet. Carbs make energy, energy makes our brain function. To lose weight: less carbs.
10-35 % are proteins.
20-35 % are fats. 15-20% Monounsaturated fats. 5-10 % Polyunsaturated fats. Less than 10 % saturated fats.
3-5 % fiber.
Less than 6gr of salt (prevents us from cramping).
3 liters of water.
Hotter area = More water.
MEDITERRANEAN: Paella, pies, olive oil.
JAPAN: Sushi, rice, fish.
UK/USA: Roast chicken rolls, turkey, pies, junk food = Obesity.
INDIAN: Rice, curries, bread.
Approximate energy content per 100g of carbohydrate, lipid and protein.
Carbs: 1760 kJ.
Fats. 4000kJ (should obtain less fats in diet).
Proteins: 1720 kJ.
It takes one hour to burn off in a 10mph run a burger and fries, 45 minutes a slice of pizza and 2 hours chinese takeaway.

Question 12

Energy distribution for athletes and nonathletes

Answer 12

The athlete requires more energy, so they eat more.
Consume significantly more carbs, considerably more proteins and slightly more fats.
Percentage difference: Slightly more carbs (need more energy), slightly more proteins (more recovery needed, more muscle growth), considerably less fats (depending on type of athlete. A sprinter may have less fat in the diet than a shot putter).
ATHLETIC DIETARY PLANS:
Michael Phelps: 12,000 calories per day whilst winning 8 gold medals.
LeBron james: 4,000 calories per day. 6 foot 8 inches.
Average male non athlete should aim for 1800-2000 calories per day.
Usain Bolt ate Chicken Nuggets during the Olympics, an average of 3,500 calories per day. Food that he trusted, to ensure he was not going to get sick.
Average female non athlete should aim for 1500-1800 calories per day.

Question 13

Carbohydrate and Fat metabolism

Answer 13

LYSIS: break down.
GLYCOLYSIS: breakdown of glucose in supply pyruvate.
GLYCOGENOLYSIS: breakdown of glycogen into glucose.
LIPOLYSIS: breakdown of fats into glucose.
GENESIS: build up, produce.
GLYCOGENESIS: conversion of glucose into glycogen for storage.
ANABOLISM: How smaller molecules are built together to create larger molecules.
When glucose is stored as glycogen within our body.
CATABOLISM: Large molecules being broken down into small molecules. Breaking down a larger molecule into a simpler one. This can be done with oxygen, AEROBIC CATABOLISM or without oxygen, ANAEROBIC CATABOLISM.
Lipolysis, glycogenolysis, glycolysis.
Both of these processes make up our metabolism. METABOLISM is all the biochemical reactions that take place within the human body. When having a fast metabolism, one can burn the calories off. These biochemical reactions that take place within the body can speed or slow this process. One will burn more calories at rest and during activity. A high metabolism means one will need to take in more calories to maintain the weight. That is one reason why some people can eat more than others without gaining weight.
TRIGLYCERIDE STORAGE
GLYCOGEN: Is stored glucose combined together with another glucose molecule to make a disaccharide via the condensation reaction. It happens again and again, and we get polysaccharide. Chains can build up to 60,000 glucose molecules in a glycogen molecule and we store this in the liver and in our skeletal muscles.
TRIGLYCERIDE STORAGE: In the adipose tissue, in the fat cells and in the muscle itself. Unused glycogen can be transferred into triglyceride storage as well as fats we eat within our diets.

Question 14

Role of insulin in the formation of glycogen and the accumulation of body fat

Answer 14

One eats food and the blood glucose levels increase, particularly after eating a carb-rich meal. Insulin is released by beta cells in the pancreas and the insulin goes to the blood. When the insulin is in the blood, it travels around the body, to the body cells that are requiring glucose and it tells the cells to open up and that glucose can then diffuse from the bloodstream into the cells that require the glucose for respiration.
When two glucose molecules combine together through a condensation reaction a glycosidic bond is formed and it transforms into a disaccharide. Long chain of polysaccharide if this continues. This excess glucose is stored as glycogen in muscle and in the liver. When the glycogen is stored it has been reserved for up to 10 hours. Any excess or unused glycogen can be stored as triglycerides in the adipose tissue or in the skeletal muscle.
When insulin is present it also inhibits Lipolysis, which is the breakdown of fats. Which is not goof if you’re on a high fat low carb diet, meaning fat is gonna be a part of your energy. During a “cheat day”, insulin is gonna be present in the blood. All that fat is not gonna burn your energy, it’s actually gonna sit there in store as fat.

Question 15

Glycogenolysis and lipolysis

Answer 15

LYSIS: break down. GLYCOGEN: stored glucose. Lipids: fats.
GLYCOGENOLYSIS: Breakdown of glycogen into glucose. Different from glycolysis because that is the breakdown of glucose during respiration to create energy.
LIPOLYSIS: Breakdown of fats into glucose when the fats are required. So, low intensity exercise, secondary source of energy. Lipolysis happens and it is the breakdown of lipids. Unless insulin is present in the blood (because if it is, lipolysis will be reduced and inhibited).

Question 16

Function of glucagon and adrenaline during fasting and exercise

Answer 16

FASTING
GLUCAGON: After fasting, glucose levels will drop. Glucagon is a hormone that is released by the pancreas to stimulate glycogenolysis. This accelerated the conversion of glucose in the liver. Glucagon’s job is to release the glucose stored as glycogen in the liver and to enable that in the blood so that we can get it to the cells and it is where it is needed for respiration to still take place.
ADRENALINE: During a period of fasting, blood glucose levels drop. Adrenaline is released as part of the sympathetic nervous system response. This accelerates the conversion of glycogen to glucose in the liver. Similar job to glucagon.
EXERCISE
GLUCAGON: Glucose is used to release energy as part of aerobic respiration. During exercise, the blood glucose levels will drop. Glucagon is a hormone that is released from the pancreas to stimulate glycogenolysis, which accelerates the conversion of glycogen to glucose in the liver. It does a similar job but for different reasons.
ADRENALINE: During exercise there is an increased demand for glucose within skeletal muscles for respiration. Adrenaline accelerates the conversion of glycogen to glucose in the liver.

Question 17

Role of insulin and muscle contraction on the uptake of glucose during exercise

Answer 17

During exercise, there is an increased demand for glucose to allow respiration to take place. Insulin and muscle contraction stimulate the uptake of glucose from the blood into the body cells. However, insulin levels decrease. This happens to allow an increase in glycogenolysis. Because when we do strenuous exercise, the primary provider of glucose is coming from our stored glucose within our liver.
Glucose diffusion obviously still occurs because that is how glucose gets into the muscle, but the primary source of this glucose is from the stored glycogen within our liver.
As insulin levels fall, glucagon and adrenaline levels increase, resulting in more glycogenolysis, releasing more glucose from glycogen stores and less glucose is stored within the liver and more is used for respiration.

Question 18

Diagram of the ultrastructure of a generalized animal cell

Answer 18

Animal cell = Eukaryotic cell.
GOLGI APPARATUS: The folded membranes within the cytoplasm involved in secretion and intracellular transportation. Is responsible for sending proteins and compounds out of the cell itself.
MITOCHONDRION: One mitochondria. The powerhouse of the cell. Responsible for cellular respiration and the resynthesis of ATP within the cell.
LYSOSOME: Recycle machine. When there are catabolic and anabolic reactions taking place within the mitochondria, the lysosomes pick up the excess of worn-out cell parts and they allow them to be reused for future protein synthesis.
RIBOSOME: Building blocks. These allow protein synthesis to take place and link amino acids together. Many ribosomes within the mitochondria.
NUCLEUS: Contains the cell DNA and coordinates all cell activity. Initiate all other organelles to do their job.
ROUGH ENDOPLASMIC RETICULUM: Quite close to the nucleus. Looks like a maze. It allows proteins to travel throughout the rough endoplasmic reticulum. Responsible for production, processing and transportation of proteins within the cell.

Question 19

Diagram of the ultrastructure of a mitochondrion

Answer 19

MITOCHONDRION
OUTER SMOOTH MEMBRANE: Membrane of the mitochondrion, allows small proteins to pass into the organelle.
CRISTAE: Folds in the inner membrane.
INNER MATRIX: THe space within the inner membrane.

Question 20

Cell respiration

Answer 20

RESPIRATION: The process of glucose being converted into energy. Anaerobically or aerobically.
CELL RESPIRATION: The controlled release of energy in the for m of ATP from organic compounds in cells.

Question 21

How adenosine can gain and lose a phosphate molecule and the role of ATP in muscle contraction

Answer 21

How ATP can become ADP and be resynthesized to become ATP again: Adenosine triphosphate, also known as ATP = stored energy within the cell. It is also the only way we can create energy. ATP is the body’s currency for energy. Glucose is the only thing that we can cash in to get ATP to break down to ADP to release energy.
In order to release energy, the bond between phosphates must be broken. This is broken by an enzyme called ATP. What it creates is ADP plus an inorganic P (meaning a loose phosphate) and energy is released and energy can be used.
Stuck with an ADP. Need to resynthesise this ADP into ATP to make it stored energy once more. So, the ATP synthase (synth = build up were to grow) aids this anabolic reaction and allows an inorganic phosphate to reconnect with ADP to create ATP which once more gives us stored energy. This concept just keeps happening. ATP broken down into ADP plus P plus energy released. Then ATP synthase keeps resynthesizing ATP to give us stored energy once more.

Question 22

Energy systems

Answer 22

ANALOGY: We have the phone, the tablet and the laptop. The phone has a fast load up, the tablet as well. The tablet has a slow load up. The phone is easy to use, the tablet is not as convenient because one has to get it out of the pocket, but it is still fast, and to get out a laptop one has to take it out of the bag, plug it in, find a table to sit on so it’s not overhead on the lap, etc. The phone has limited storage and battery. The tablet has more storage and battery than the phone. More complex outcomes than with a phone. The laptop is the one that has the most battery and storage of the three. More complex outcomes can be achieved.
The phone is the ATP-PC: quick reaction, limited stores, meaning limited production of ATP during the system.
The tablet is the LACTIC ACID: slightly more complex reaction but quite quick. Quick energy, lots of stores depending on the glucose within the body. However, the onset of lactic acid does kick in and it is harmful to performance.
The laptop is the AEROBIC: very complex reaction. Slow load up because of the complexity taking place in the body. It is very efficient. As long as one has enough glycogen stores, the aerobic system should be running for as long as one needs it during exercise. Hours and hours of exercise.
ATP-PC: ADENOSINE TRIPHOSPHATE PHOSPHOCREATINE SYSTEM: The fuel is phosphocreatine. Duration is up to 10 hours. Intensity: Initial stage of exercise, no matter the exercise, or maximum exercise. Example: Basketball. Running up and down the court and then all of a sudden you jump up for a rebound. You will be using your ATP-PC stores. Essentially, you stored ATP to jump up and win the rebound and the more you do that the more you’ll be using this system. The amount of ATP per PC is one. One ATP can be resynthesized by one phosphocreatine. No by products, advantage.
LACTIC ACID: Glucose is the main fuel (glycogen). For up to 75 seconds. 400 meter runner. The last meters you feel it in your legs. This is lactic acid taking over because there is no oxygen and your body is screaming for oxygen, your muscles are screaming for oxygen and the hydrogen ions are creating lactic acid in the muscles. The amount of ATP per glucose molecule is two to three. Is two or three ATP that can be resynthesized per glucose molecule. By products: lactic acid. Intensity: 75 % - 90 % MAX HR.
AEROBIC SYSTEM: The fuel is glucose, lipids and protein. Glucose is the main source of energy, once your glucose stores deplete or you have a diet where you don’t take carbs, lipids can be used for the aerobic system and in extreme situations (extreme marathon) proteins will provide fuel and be broken down into glucose and resynthesize ATP. It lasts between 75 seconds until the exercise finishes, which could be hours. The intensity is from 60 % to 80 % MAX HR. Amount of ATP per glucose molecule is 34. So 34 ATP per glucose molecule as opposed to 2 or 3. By products: Carbon dioxide, water, heat.
During exercise:
The second you start moving, your stored ATP is your primary provider of energy. Thi lasts 3 seconds. Gives time for the others.
After that, the ATP-PC system is really taking over providing the energy up to 10 seconds, where that drops off.
After that, the lactate system takes over and provides the most energy for us for 75 seconds.
75 seconds is enough time for the aerobic system to kick in and if you are going for a longer exercise than 5 seconds, the aerobic system is up and running and resynthesizing ATP at a very good rate. Can do this for hours.
Reactions:
ATP-PC: Simple reaction. Adenosine and three phosphates. One of the phosphates gets released from this chain and it is ATP’s enzyme that allows this to happen. Whilst this phosphate is being released, energy is being released. So that energy can be used within the muscle cell. To resynthesize the ATP, a phosphocreatine must release the phosphate molecule and his creatine kinase that allows this catabolic reaction to take place. CREATINE KINASE catalyzes a phosphate to move from CP to ADP to resynthesize ATP.
GLYCOLYSIS: The process in which glucose is catalyzed into pyruvates (PYRUVIC ACID). Catabolic reaction. Breaks down glucose into two carbon chains of pyruvates.
ANAEROBIC GLYCOLYSIS: Lactic acid system. If oxygen is absent.
AEROBIC GLYCOLYSIS: Aerobic system. If oxygen is present. Prevent the onset of lactic acid and that be your aerobic system firing up.
ANAEROBIC GLYCOLYSIS: Glucose molecule is broken down into two pyruvates. This can yield 2 or 3 ATPs. This reaction occurs in the cytoplasm of the cell. It does not take place in the mitochondria. If oxygen is present, then these 3 carbon chains can be converted from pyruvate into something called ACETYL COENZYME A which enters the KREBS CYCLE.
Once the Krebs cycle is up and running, and our electrons have been liberated, they can answer the electron transport chain which is a real moneymaker and this is where 34 ATP per glucose molecule and be resynthesized.
AEROBIC GLYCOLYSIS: In the presence of oxygen, the pyruvates enter the mitochondria. Difference between anaerobic and aerobic glycolysis. Here, the pyruvates can be converted into Acetyl coenzyme A. This is now in the Krebs cycle.
It is called the Krebs cycle because it is named after a guy who discovered the citric acid cycle which is its alias. Here, hydrogen ions liberate electrons for the electron transport chain. NAD - NADH+ (hydrogen ions) & FAD - FADH+ (hydrogen ions).
ELECTRON TRANSPORT CHAIN: Electrons have been liberated. These electrons are what resynthesize ATP and they are what reproduce and resynthesize 34 ATP per glucose molecule.
If you had a sugar cube announced to buy you for three pounds (anaerobic - lactic acid) or 34 pound (aerobic - krebs cycle + electron transport chain). More happy with the 34. But it takes longer because of the complex reactions.
When glucose stores are low or we are not using glucose, lipids are broken down to create glucose. This is lipolysis. When oxygen is present, fats are broken down by beta oxidation and with this liberation a greater number of electrons, over 100 ATP, can be resynthesized per fatty acid. The reason fats are your main energy source for very low level exercise. Fantastic secondary source of energy.

Question 23

Phenomena of oxygen deficit and oxygen debt

Answer 23

OXYGEN DEFICIT: Difference in the oxygen that your muscles demand against the oxygen that you can actually provide the muscles. Warm up: working your system for a couple of minutes to get in the aerobic system. With prolonged exercise you get a steady state of maximum oxygen. End of exercise = oxygen debt. More apparent with anaerobic exercise or a sprint. Even after a prolonged exercise you will still have an oxygen debt. Repaying the oxygen that you borrowed back to your muscles. When you finish exercising, and stop immediately, you would still be breathing deeply, heart faster. Returning oxygen that has been borrowed. Owe oxygen back to your body systems.