Human Biology IB (Bioenergetics)

LEARN ALL ABOUT ENERGY IN THE HUMAN BODY

" ...it is very informative and worthwhile. I am glad I started the course. Of the many available from different schools, this offers the best value for money. "
- Sonia, studying Human Biology

The information given was excellent, but the assignments also made you look further to find answers yourself and I find this a much better way of learning than just being handed all the answers. It has given me a grounding knowledge in human biology which is perfect as I am applying to study Chiropractics at university next year. I couldn’t have asked for more from my tutor. She was very thorough and extremely helpful with any problems I encountered."
- Kate, Anatomy 

Discover how energy affects our body, how to manage people's energy, where it comes from and what affects energy levels. Learn about energy and movement within the human body. What are the factors that makes us move better?. By understanding these factors you can better manage people's capacity to move, and to manage optimum levels of energy within their body.

The lessons cover: energy and work; energy pathways; the acid-base balance; osmosis & diffusion; atmospheric pressure; temperature regulation; ergogenic aids to performance

Prerequisite: A basic understanding of body systems (e.g. Human Anatomy and Physiology).

Lesson Structure

There are 7 lessons in this course:

1. Energy and Work
   • Anaerobic energy supply
   • Phosphate energy
   • Lactic acid energy
   • Adenosine triphosphate
   • Aerobic energy supply
   • Energy requirements for different types of activity
   • Breathing during exercise
   • ATP movement
   • ATP sources
   • ATP-PC system
   • Lactic acid system
   • Oxygen system
   • Aerobic systems
   • Krebs cycle
2. Energy Pathways
   • What is energy
   • The nature of energy
   • Units of measurement
   • Production and storage of energy
   • Carbohydrates in an animal or human body
   • Glycogenesis
   • Glycogenolysis
   • Gluconeogenesis
   • Hyperglycaemia
   • Carbohydrate oxidation
   • Glycolysis
   • Hydrolysis
   • Hydrolysis of metal salts
   • Hydrolysis of an ester link
   • Energy production pathways from different foods: fats, carbohydrates, proteins
   • Respiratory quotient
   • Resting quotient
   • Aerobic capacity
   • What happens during exercise
   • Recovery from exercise: Alactacid and lactacid oxygen debt, Replenishing muscular glycogen
   • Lactic acid
   • Calculations
3. The Acid-Base Balance
   • pH
   • What is acidity
   • The urinary system: Kidneys, ureters, bladder
   • Physiology of the Urinary system
   • The urea cycle
4. Osmosis and Diffusion
   • Diffusion explained and examples given
   • Nature and types of diffusion
   • Movement of molecules through cell membranes
   • Endocytosis
   • Membranes and their structure
   • Osmosis
   • Osmosis and filtration
   • Membrane transport: simple passive, active and facilitated transport
   • Chemical potential
   • Osmotic pressure
   • Reverse osmosis
5. Atmospheric Pressure
   • Altitudes
   • Introduction to atmospheric pressure
   • Partial pressure gradients
   • Effects of change in pressure
   • Equalising when diving
   • Gas solubility
   • Breathing at different atmospheric pressures
   • Calculations
6. Temperature Regulation
   • Introduction
   • Affect of temperature changes on the human body
   • Conduction and convection
   • Lowering temperature: sweating, vasodilation, metabolic reduction, hair, behaviour
   • Raising temperature
   • Vasoconstriction
   • Increased metabolism
   • Behaviour
   • Effect of temperature on enzymes
   • Eccrine glands
   • Apocrine glands
   • Energy production
   • Factors affecting individual BMR: growth, body size, food, thyroid gland
   • Fever: mechanism of fever, shivering, other temperature disorders
   • Grades of fever
   • Signs of fever
7. Ergogenic Aids to Performance
   • Introduction
   • Drugs: steroids, amphetamines
   • Oxygen
   • Vitamins
   • Water
   • Other foods: carbohydrates, protein
   • Creatine
   • Caffeine
   • Antioxidants

Aims

• Explain how energy is used in the human body to create work and power.
• Explain energy pathways during resting, work and recovery.
• Explain the significance of the acid-base balance in the body.
• Explain movement of materials in and out of living cells.
• Explain the affect of changing atmospheric pressure on the body.
• Explain temperature regulation in the body.
• Explain ergogenic aids to body performance during activity/exercise.

What You Will Do

• Explain biological energy cycles, using illustrations where appropriate.
• Explain two examples of energy pathways in the body, including an anaerobic and an aerobic pathway.
• Explain the function of ATP in body energy pathways.
• Explain the significance of the following terms to understanding body energy pathways:
  • energy
  • work
  • power
  • efficiency during exercise
• Explain the consumption of oxygen during different stages of activity, including:
  • at rest
  • warming up
  • peak activity
  • cooling down
• Calculate the net cost of exercise in litres per minute, for a set situation.
• Explain the measurement of efficiency during the exercise carried out in a set task.
• Explain problems which may occur in physiological processes during running a marathon.
• Explain in one paragraph for each, the following acid-base terms with relevance to exercise:
  • Buffer
  • Alkali reserve
  • Alkalosis
  • Acidosis
• Describe respiratory regulation of pH in the human body.
• Describe how regulation of pH occurs in the kidneys.
• Explain the affect of strenuous exercise on body pH.
• Explain osmosis in a specific biological situation (of your choice).
• Distinguish between diffusion and facilitated diffusion in the human body.
• Explain how electrochemical forces maintain cellular equilibrium.
• Explain how active transport mechanisms occur at a cellular level.
• Describe three situations where pressure changes can affect body function, including:
  • scuba diving
  • mountain climbing
• Explain the effects of pressure changes on different parts of the body, including examples of changes due to altitude and scuba diving.
• Explain the effect of a decompression treatment on a diver suffering from nitrogen narcosis.
• List mechanisms of heat loss in the human body.
• List mechanisms of heat gain in the human body.
• Explain the operation of thermal receptors and effectors in the human body.
• Describe the exercise session which you underwent in your set task, and explain the maintenance of body temperature during that exercise session.
• Explain how temperature regulation may be different during peak exercise, to what it may be during exercise at 60-70% effort.
• Explain the affects of steroids on the body, in relation to both performance, and other health factors, during two different types of activity.
• Explain the affect of amphetamines, and other performance enhancing drugs on the body, during an activity of your choice.
• Compare the advantages and disadvantages of amino acid use to enhance physical activity.
• Explain the use of blood doping to enhance physical performance in a specific activity.
• Explain ways oxygen can be used to enhance performance in a specific activity.
• Explain the effect of different vitamins on three different types of performance.
• Explain the affect of aspartic acid salts on a specific performance.

Sugars - glucose or glycogen are absorbed into the blood in the form of blood sugars, and transported to various parts of the body, particularly muscles and the liver. In most cases, except nerve tissues, the enzyme "insulin" is needed to facilitate the transfer of these sugars through the cell walls, inside muscle cells. Other chemicals, such as Phosphatises and hexokinases are also needed to facilitate transfer of sugars through the cell wall.

Glucose is not stored, but can change to glycogen, which is stored. Glycogen is essentially a string of glucose molecules linked together by single phosphorus atoms.

 
CARBOHYDRATES IN AN ANIMAL OR HUMAN BODY
Carbohydrates, specifically glucose provide the main source of energy in the body.  Immediately after eating, blood sugar - glucose levels rise. In response to these increased levels the pancreas, in higher animals and humans releases insulin, which is a hormone, which increases the rate of absorption of glucose f\out of the blood and into cells.  Glucose may then be used as energy, or in the liver and muscles, converted into glycogen for storage.

Glycogenesis
A series of chemical reactions which changes glucose into glycogen. Glycogen is a molecule which can be stored in the body, whereas high levels of glucose cannot be stored. As glycogenesis occurs, the level of blood sugar drops back to normal levels.

If blood sugar levels become too low, the pancreas stops releasing insulin, and begins releasing glucagon.  Glucagon, like insulin is a hormone, but it acts in opposition to insulin, stimulating the conversion of stored glycogen into glucose by the liver, and the release of the glucose by the liver into the blood stream.  The blood then supplies glucose molecules to cells which transport them inside and utilise them for energy to drive their biochemical processes.