Bioenergetics Flashcards
5 concepts in Bioenergetics
Thermodynamics Redox reactions ATP (adenosine triphosphate) biological catalyst - Enzymes Hydrogen shuttles
What are the two law of thermodynamics?
- energy can not be created or detroyed, it is only transformed
- the entropy must decrease
What is the link between the course and the 1rst law of thermodynamics?
glucose–>energy (chemical energy)
What is the 2 links between this cours and the 2nd law of thermodynamics?
- food –> ATP + HEAT
2. enthropy is required to maintain order of the cells –> homeostasis
What is the use of the heat created when food is converted into ATP?
it regulates/keeps body temperature.
What is a redox reaction?
a reaction that combines oxidation and reduction?
What is reduction?
It requires and imput of energy where the molecule loses and O and gains a H
What is a oxidation?
It realases energy by adding a O and loosing a H.
Which are the food with the most calories?
The food having a higher H:O ratio. The more there are H to loose, the more potential energy the molecule has.
Between fatty acid (18:1) and glucose (2:1), which one is the most caloric or has more enrgy to release?
the fatty acid because the H:O ration is bigger.
What does ATP stands for?
adenosine triphosphate
How does ATP releases energy?
By hydrolysis
What is the reaction of ATP hydrolysis?
ATP + H2O –> ADP + P + Energy
Why does ATP has a high phosphate transfer potential?
Because it is a very good donor. it donates phosphate to acceptor very easily.
Give an example of a reaction with ATP.
Synthesis of glucose-6-phosphate
How does the reaction of glucose-6-phosphate go?
ATP+H2O –> ADP +P
glucose + P –> G-6-P + H2O
(simultaneously)
What is ATP used for in anial cells?
Biosynthesis - synthesis of proteins
Active transport - move vessicles, ion pumps,…
MOvement - muscle, GI track
In what is ATP converted after it is used for it’s many purposes?
ATP is converted into ADP + P
How is ADP converted into ATP?
With cellular respiration
food + O2 –> CO2 + H2O
ADP + P –> ATP
WHat is the solution our body has developp to fulfill the high demand in energy?
The ATP is recycled
What are the caracteristics of enzymes?
- lowere the energy of activation of a reaction
- are substrate specific
- (many) require co-factor
- activity affected by environment
- organized in metabolic pathways (break down the steps of the reaction so many enzymes are responsible for 1 part of the large reaction)
How do enzyme lower the energy of activation?
by forming enzyme-substrate complex
What does it mean that enzyme are substrate specific?
It means that they can only bind to specific molecules for specific reactions.
What are the kinds of co-factor used by enzymes?
vitamins, minerals
What are the conditions that need to be specific to every enzyme so they can work best?
temperature
pH
substrate concentration and products
What happens if one enzyme does not work?
the other enzymes can not complete the reaction.
What is heydrogen shuttles?
It is a transfer of hydrogen
What are the three types of H shuttles?
NAD+/NADH
FAD/FADH2
NADP+/NADPH
What does NAD+/NADH do?
- breaks the C-H bonds in organic food
2. transfers H from food to O2 to make water
What does NADP+/NADPH do?
tranfers H from water to organic molecules
