Ex Phys Chapter 2 Flashcards
Fuel sources from which we make energy (adenosine triphosphate [ATP])
Substrates
Carbohydrates, fat, and protein are all examples of ____
substrates
the process of converting substrates to energy
performed at a cellular level
Bioenergetics
A chemical reaction in the body
metabolism
heat energy required to raise 1g of water from 14.5°c to 15.5°c
1 calorie
1,000 cal = 1
kcal= dietary calorie
Resting metabolism consumes
50% carbohydrates and 50% fats
exercise for short periods consume more
carbohydrates
exercise for longer periods of time consumes
carbohydrates & fat
all carbohydrates are converted to
glucose
the primary ATP substrate for muscles
Glucose
extra glucose is stored as ______ in the liver and muscles
glycogen
The glycogen stores in the body are limited to
2500 kcal
what substrate is
-4.1 kcal/g
-& Must be converted into glucose (gluconeogenesis)
(only used during starvation)
Protein
____ can also convert into FFAs for energy storage and cellular energy substrate. This process is called
Protein & lipogenesis
supplies 5-10% of energy for prolonged exercise
protein
Factors to control the rate of free-energy release are
- Availability of the primary substrate
- Enzyme activity
What does the following:
- Doesn’t start chemical reaction or set ATP yeild
- facilitates breakdown (catabolism ) of substrates
- lower the activation energy for a chemical reaction
- end’s with suffix ase
enzymes
Each step in a biochemical pathway requires specific
enzymes
more enzyme activity = more
product
- Can create bottleneck at an early step
- Activity influenced by negative feedback
- Slows overall reaction, prevents runaway reaction
Rate-limiting enzyme
major fat energy source
triglycerides
the process of fat oxidation carried out by lipases is
Lipolysis
substrates are most commonly composed mostly of
carbon, hydrogen, oxygen, and nitrogen
(a one unit sugar) glucose is considered a
monosaccharide
(a multi unit sugar) glycogen is a
polysaccharide
____ are the only energy source used by brain tissue
carbohydrates
only ___ are used to form ATP
FFAs
_____ are a key structural component of all cell membranes and forms a protective sheath around some large nerves
phospholipids
the influence of substrate ability on the rate of metabolism is termed at the
mass action effect
an important enzyme that breaks down ATP and releases stored energy is known as
Adenosine Triphosphatase
this enzyme is usually located early on in a metabolic pathway and is key for controlling the reaction’s overall rate
rate-limiting enzyme
an atp molecule is composed of
adenosine combined with 3 inorganic phosphate (P1)
when an ATP molecule is combined with water (hydrolysis) and acted on by the enzyme ATPase
the last phosphate splits away rapidly releasing a large amount of energy
