Energy Sources (Part 1) Flashcards
What can be defined as the capacity to do work?
Energy
What 3 things is energy needed for?
- Mechanical Movements
- Protein synthesis
- Storage of fuels
Define a calorie
The heat necessary to raise the temperature of 1 kg of water 1⁰C
How many kcal do you need per hour?
1 kcal per kg of body weight
What are the 3 macronutrients?
- carbohydrates
- lipids
- proteins
1 gram of carbohydrate = __ kcal
4
What percentage of daily caloric intake should be comprised of carbohydrates?
40-50%
1 gram of fat = __ kcal
9
What percentage of daily caloric intake should be comprised of fats?
25-30%
1 gram of protein = __ kcal
4
What percentage of daily caloric intake should be comprised of proteins?
15-20%
What are the 6 categories of nutrients?
- Carbohydrates
- Lipids
- Proteins
- Vitamins
- Mineral
- Water
Vitamins and minerals are considered ____nutrients
micro
What is the difference between vitamins and minerals?
- Vitamins are organic and can be broken down by heat, air, or acid
- Minerals are inorganic and hold their chemical structure
What are the 7 functions of vitamins and minerals?
- build strong bones
- heal wounds
- bolster the immune system
- convert energy into energy
- repair cellular damage
- prevent birth defects
- strengthen teeth
Which vitamins and minerals build strong bones?
- calcium
- vitamin D
- vitamin K
- magnesium
- phosphorus
Which vitamin prevents birth defects?
folic acid
Which mineral strengthens teeth?
flouride
What is the ultimate source of all energy on earth?
the sun
Plants convert sunlight to which macronutrient?
carbohydrates
What are the 4 forms of energy?
- Chemical
- Electrical
- Heat
- Mechanical
What are carbohydrates composed of?
atoms of carbon, hydrogen, and oxygen
What are the 3 functions of carbohydrates?
1) Provides energy for cellular metabolism
2) Forms glycogen in the liver and muscles
3) Converts to fat (triglycerides) for later use
What are simple carbs obtained from?
Foods that are refined and packaged, such as sugar, honey, milk, and fruit juices
What are the 3 forms of carbohydrates?
- Monosaccharides
- Disaccharides
- Polysaccharides
What are the 3 monosaccharides?
- glucose
- fructose
- galactose
Which simple sugar (monosaccharide) is the only form of carbohydrate that can be directly metabolized to obtain energy?
glucose
What are disaccharides composed of?
2 monosaccharides
2 glucose molecules can combine to form what disaccharide?
maltose
1 glucose molecule and 1 fructose molecule can combine to form what disaccharide?
sucrose
What are polysaccharides composed of?
3 to hundreds of monosaccharides
What are the 2 most common plant polysaccharides?
starch and cellulose
What polysaccharide form is the one in which animals store carbohydrates?
glycogen
What is glycogenesis?
The synthesis of glycogen in the liver or muscle from glucose molecules
What is Glycogenolysis?
The process in which glucose molecules are removed from glycogen in the liver
Describe complex carbs
They are essentially a carbohydrate that consists of two or more monosaccharide units (disaccharide/polysaccharide). Because of this they will take longer for the body to convert into sucrose or glucose which provides a steady release of energy into the body
What are some examples of complex/good carbs?
- vegetables
- oatmeal
- various types of legumes
- dark breads
- beans
- pasta
What are the 2 fats important for metabolism?
- fatty acids
- triglycerides
What is a fatty acid?
A compound composed of a carbon chain and hydrogen atoms with an acid group at one end (COOH) and a methyl group (CH3) at the other
How are fatty acids classified?
As saturated (animal) or unsaturated (plant)
What is a saturated fatty acid?
A fatty acid containing the maximal number of hydrogen atoms and no double bonds between the carbons
What is an unsaturated fatty acid?
A fatty acid that does not contain the maximal number of hydrogen atoms and there is at least one double bond between the carbons
Are saturated or unsaturated fatty acids better for you?
Unsaturated
Within the body what are fatty acids stored as?
triglycerides
What is a triglyceride composed of?
A glycerol molecule and 3 fatty acids
What are the 4 roles of lipids in the body?
1) Energy source and reserve
2) Protection of vital organs
3) Thermal insulation
4) Vitamin carrier
True or False
Protein is only found in animal sources
False, it can be found in both animal AND plant
What molecules compose all proteins?
amino acids
How many amino acids are there? How many are essential and how many are nonessential?
20
9
11
What are essential amino acids?
Amino acids that must be ingested in food because they cannot be synthesized
What are nonessential amino acids?
Amino acids that can be synthesized by the body
Is a large or small amount of protein metabolized to provide energy? Describe why…
Small, largely due to the nitrogen atom
What are enzymes?
Protein molecules that facilitate a chemical reaction by lowering the energy needed for the reaction to take place. Therefore they facilitate and increase the speed of the reaction
An enzyme participates in 1 of 2 types of reactions what are these 2 reactions?
catabolic or anabolic
Describe the difference between catabolic and anabolic reactions
Catabolic reactions break down a substrate thus releasing energy
Anabolic reactions occur when one product is formed from 2 substrate molecules, which requires energy
What is the major factor in which the type of enzymatic reaction depends on?
mass action affect
What are the 2 factors which affect the speed with which enzymes facilitate their respective reactions?
temperature and acidity
The _____ in temperature and ______ in acidity that occurs during exercise tends to increase the speed with which an enzyme facilitates its reactions
increase
increase in acidity (decrease in pH)
Is the energy liberated during the breakdown of food used directly for work?
No, it is stored as ATP which is then used to produce work
What are 3 energy yielding sources?
- aerobic metabolism
- anaerobic metabolism
- ATP-PC system
True or False
All products produced by aerobic metabolism (energy, CO2, and water) can be readily used and expelled
True
When is aerobic metabolism used?
during rest and long-duration, low intensity exercise
What molecules can be aerobically metabolized to supply energy?
- carbs
- triglycerides
- protein
__% of energy during rest comes from what during rest
60
fat
What is the only thing that can be used to produce energy anaerobically?
carbohydrates
Anaerobic metabolism of carbohydrates results in the production of what?
lactic acid
What is the main advantage of anaerobic metabolism?
The energy that it yields is made available quickly to the exercising muscle
What are the 2 major energy sources during high-intensity, short-duration activity?
- anaerobic metabolism of carbohydrates
- phosphagen system
What is ATP composed of?
- Adenine
- Ribose
- 3 Phosphate molecules
What can ATP be produced from?
ADP + Pi + H+
When ATP is broken down energy is released and acidity _____.
increases
Where does the energy required to produce ATP come from?
From the breakdown of phosphocreatine in the ATP-PC system
When is the ATP-PC system used?
For physical activities that require a lot of energy per second and are relatively short in duration
What enzyme facilitates the breakdown of ATP to ADP and Pi?
ATPase
What enzyme facilitates the breakdown of phosphocreatine to Pi and creatine?
Creatine kinase
The Pi is then used to produce ATP
During maximal intensity activity ATP and PC intramuscular concentrations will be depleted in about __ seconds
4
Describe how high intensity training helps to improve performance
Creatine combines with inorganic phosphate via the enzyme creatine kinase to form PC which can then be used to replenish ATP. Intramuscular ATP and PC concentrations increase in response to short-duration, high-intensity activity which may enhance performance
Which anaerobic pathway results in the production of lactic acid?
anaerobic glycolysis
In order to burn off the calories from eating one banana, how far must you run/walk?
Run or walk 1 mile
As the intensity of an exercise increases which energy system do you utilize?
anaerobic glycolysis
What is glycolysis?
the breakdown of glucose by enzymes, releasing energy and pyruvic acid
1 ATP = - kcal
7-10
