Metabolism and Enzymes Flashcards
What is metabolism ?
general term used for all of the reactions occurring in cells
What is catabolism ?
the metabolic breakdown of complex molecules into simpler one
- results in energy release
What is Anabolism ?
phase of metabolism where simple substances are built into complex ones
- results in cells taking energy to create structures within the cell
- uses the building blocks to synthesize macromolecules for growth and reproduction
When do catabolism and anabolism occur ?
happen all the time in the body
What happens to the molecules in catabolism ?
large molecules are broken down into small ones and energy is released
- energy is released and stored in cells as ATP
What happens to the molecules in anabolism ?
small molecules are assembled into larger ones and energy is required for this
- uses energy from building blocks and ATP from catabolism
What is needed for cells to create structures, cell walls, and genetic material ?
the catabolism and anabolism process is needed
What do most bacteria use as the energy source in catabolism ?
glucose
- it’s a common carbohydrate
What is a catalyst ?
increases the rate of a reaction that would normally occur at a slow rate
What happens after catabolism and anabolism occurs in a cell ?
the cell will break into 2
What is a substrate ?
the chemical compound that will speed up the reaction and fits into enzyme perfectly
Where in the enzyme does the substrate fit ?
in the enzyme’s active site
What is the cofactor ?
sometimes present in the enzyme to ensure the substrate fits better
What is the lock and key with the enzyme and substrate ?
- lock: enzyme
- key: substrate
Is the enzyme ever changed during a reaction ?
no
- it can be used so many more times over again
What is the activation energy ?
amount of energy needed to trigger a chemical reaction
How do enzymes affect the activation energy ?
the enzymes will lower the activation energy
- makes reactions go faster
What has higher energy, the substrate or the product ?
the substrate
What happens once the activation energy is reached ?
the reaction occurs
Is the activation energy higher or lower with the enzyme ?
lower so the line will be lower in the graph
Is the activation energy higher or lower without the enzyme ?
higher so the line will be higher in the graph
How are enzymes named ?
named after the substrate or reaction they catalyze
- ends with -ase (usually)
- some enzymes still go by old name like trypsin or pepsin
What are the 2 main pathways that cells use for producing energy from nutrients ?
- fermentation
- respiration/oxidation
Which energy pathway is oxygen needed for ?
respiration/oxidation
Which energy pathway is oxygen not needed for ?
fermentation
Which energy pathway produces more energy ?
aerobic respiration/oxidation makes the most (about 36 ATP)
What is the final acceptor in fermentation ?
pyruvic acid
- organic molecule
In fermentation what are the end products ?
lactic acid and ethanol
- lactic acid from animals
- ethanol from yeast
Which energy pathway produces the least amount of energy ?
fermentation (anaerobic)
- about 2 ATP
What is the final acceptor in respiration/oxidation ?
CO2 (carbon dioxide) and H2O (water)
- inorganic molecule
Where can aerobic respiration take place ?
cytoplasm and the mitocondria of the cell
- takes place in higher organisms
Is the aerobic respiration complete or incomplete oxidation of substrate ?
complete oxidation
Where does anaerobic respiration take place ?
cytoplasm only
- occurs in lower organisms like bacteria, yeast, etc
What are some things that Aerobic and Anaerobic respiration have in common ?
- makes ATP
- makes CO2 (dioxide)
- use glycolysis
What are some unique things to just Anaerobes ?
- no 02
- makes lactic acid
- makes ethanol
What are some unique things to just aerobes ?
- uses 02
- uses citric acid cycle
- uses oxidative phosphorylation
