Chapter 7 : Microbial Metabolism (diana's version) Flashcards
This is the sum of all chemical reactions that occur within an organism
Metabolism
Define the term metabolism
metabolism is the sum of all reactions that occur within an organism
metabolism can be divided in two classes :
the two classes of catabolism and anabolism
what does catabolism mean?
catabolism means that reactions that generate energy
- breakdown of complex organic compounds into simpler ones
for example: proteins are broken down into their amino acid components, releasing energy
What does anabolism mean?
reactions that require energy
the biosynthesis or building of complex organic molecules from simpler ones
for example : amino acids are used to build proteins, consuming energy
energy is stored in the form of _______
ATP
True or false.
the bonds in between each of three phosphate groups are very high energy
True
breaking what bonds releases lots of energy and serves as a driving force for other chemical reactions
ATP
catabolic reactions ____ ATP
generate
Anabolic reactions ____ ATP
consume
Nicotinamide adenine dinucleotide
NAD is the what form?
this is the oxidized form
Nicotinamide Adenine Dinucleotide
NADH + H: is what form?
this is the reduced form
NAD acts as …..
and provide an example
it acts as an electron carrier
- for example : electrons originate on donor molecules such as glucose
2 electrons are removed from the donor molecule and added to NAD+
this is what concept?
concept of oxidized and reduced ( basically means from that statement that 2 protons (H+) are also transferred
NAD+ 2e- + 2H ——-> NADH + H
In the collision theory, define the characteristics
-Atoms and molecules are in continuous motion
-as a result of this random motion collisions occur in between the atoms and molecules
-these collisions result in chemical bonds being broken in reactants and formed in products
-There is a minimum amount of energy needed for a reaction to occur-it is called the activation energy
If this amount of energy is not achieved than the reaction cannot occur
what are some certain ways that can be done in order to increase the reaction rate (the speed at which the chemical reaction proceeds):
- increasing the temperature
2.increasing the pressure
3.adding an enzyme
name a characteristics about enzymes
function as catalysts that lower the activation energy of a particular reaction
The enzyme is not altered in this process and can be reused
- each enzyme acts on specific substrate
( a particular enzyme catalyzes only one reaction)
True or false:
the enzyme lowers the activation energy by positioning the substrate such that there is greater probability that the reaction will take place
True
Fun fact: with an enzyme present reactions can occur up to 10 billion times faster than without enzyme
**just a fun fact you should have a bit of knowledge about ***
Carbohydrate Catabolism : name the characteristics
this is the breakdown of carbohydrates in order to release energy
the most common carbohydrate used by cells for energy is glucose
what are the two processes can be used to catabolize glucose:
cellular respiration and fermentation
define cellular respiration:
occurs when oxygen is present
- much more efficient than fermentation
-releases 32 ATP
define fermentation:
occurs when oxygen is absent
-less efficient
-releases only 2 ATP
define cellular respiration(steps) :
this occurs in three main stages
1. Glycolysis
——- Intermediate Step——-
2.Kreb’s cycle (Citric Acid Cycle TCA cycle)
3. Electron transport chain
define glycolysis :
this is the splitting of sugar (glucose) into smaller molecules
- occurs in a sequence of 10 reactions ( each step requires a unique enzyme)
one glucose is converted into 2 molecules of pyruvic acid (pyruvate)
This reaction can occur in the presence or the absence of oxygen
Only a very small amount of energy is released from this reaction
- 2 ATP
-2 NADH + H+