Metabolism L1: Introduction to metabolic pathway Flashcards
What are the 3 stages after chew and swallow food?
- Digestion
- Absorption
- Metabolism
_____ are the only ones that diffuse passively across the membrane
Lipids
What is digestion?
Food is broken down into minuscule nutrients in the stomach
What is absorption?
The nutrients are absorbed into the blood stream from the small intestine
What is metabolism?
After the nutrients are absorbed into the blood stream and travel to all cells of all the body, metabolism occurs
Your body _____ the food you eat, both, to use immediately or to store as energy for later demands
metabolises
What are 6 macronutrients?
- Carbohydrates
- Fat
- Protein
- Vitamins
- Minerals
- Fibre
What is the function of carbohydrates?
Fast (easy-access) energy
What are 5 functions of fat?
- Stored energy
- insulation
- vitamin
- hormone building
- cell membranes
What are 4 functions of protein?
- Building cell structures
- oxygen transport
- immune defenses
- chemical reactions
What are the building blocks of carbohydrates?
Saccharides (sugars)
What are the building blocks of fat?
Fatty acids
What are the building blocks of protein?
Amino acids
What are some examples of carbohydrates?
Glucose, sucrose, dextrose, maltose, lactose, fructose, cellulose, amylose
What are some examples of fat?
Unsaturated and saturated fats
What are some examples of proteins?
Membrane receptors, hemoglobin, antibodies, enzymes
___ % of our energy comes from carbohydrates.
45-65%
___ % of our energy comes from fats.
<30%
___ % of our energy comes from protein.
12-20%
getting sufficient vitamins and minerals are sometimes a problem for people in ________.
developing countries
In carbohydrates, ______ is the principle fuel in the short term
Glucose
Why is carbs the principle fuel in the short term?
Highest amount of ATP compared to others
Sugar based –> taken up by body and used as energy first
Carbohydrates (glucose) yields is about ____kcal/g
4
Glucose is stored as _____
glycogen
Humans can synthesis ____ (all/some/none) the carbohydrates they need
all
What are 4 characteristics of carbohydrates (glucose)?
- Glucose is the principle fuel in the short term
- It yields is about 4kcal/g
- Stored as glycogen
- Humans can synthesis all the carbohydrates they need
Lipids have the highest calorific value of _____kcal/g
9
Lipids are secreted as _____
fatty acids
Lipids are stored as ______ (fatty acids + glycerol)
triacylglycerols
Lipids are use when fuel is ______ or _______.
short supply; prolonged energy expenditure
What are 4 characteristics of lipids?
- Stored as triacylglycerols (fatty acids + glycerol)
- Highest calorific value 9kcal/g
- Secreted as fatty acids
- Used when fuel is in short supply or prolonged energy expenditure
Proteins are polymers of ______
amino acids
Proteins are ____ amino acids, _____ cannot be synthesised by humans = essential amino acids
20; 9
What are essential amino acids?
cannot be synthesised by humans
How many essential amino acids are there?
9
What are 3 characteristics of proteins?
Not stored for energy but can be used as a fuel source in times of need
Polymers of amino acids
– 20 amino-acids, 9 cannot be synthesised by
humans = essential amino acids
– Not stored for energy but can be used as a
fuel source in times of need
Why are proteins almost never used for energy? What do you use amino acids for?
- Building blocks for cells and build proteins
- Only used in malnutrition (as 9 amino acids cant be synthesised) –>Start to digest yourself (eating up muscles)