Nutrition and Enzymes Flashcards
What is nutrition?
the process by which nutrients are acquired from the environment and used in cellular activities such as metabolism and growth
T/F micronutrients are needed in large quantities
false
What are some common macronutrients?
C,H,N,O,P,S
Macronutrients are needed in _________ quantities and are regarded as the ______ _________ of the cell.
large, building blocks
What are some common micronutrients?
Mn, Ni, Zn, Cu
T/F trace metals are typically associated with enzymes?
T
What are growth factors?
organic compounds that are essential cell components or precursor components that cannot be synthesized by the cell
T/F all microbes can make all necessary growth factors, explain why
false, some can, others obtain from the environment
T/F growth factors are considered micronutrients, and are absolutely necessary
T
What are the 3 main categories of growth factors?
amino acids, purines and pyrimidines, vitamins
What are the most common growth factors?
vitamins
When associated with enzymes, growth factors are called enzyme _______
cofactors
T/F carbon makes up 50% of a microbes dry weight
true
Carbon is the ________ of all macromolecules (proteins, lipids, sugars)
backbone
If a bacterium uses organic compounds such as amino acids, fatty acids, and sugars as a carbon source they are classified as ____________
heterotrophs
If a bacterium uses inorganic compounds such as carbon dioxide, mineral deposits, and calcium carbonate as a carbon source they are classified as ___________
autotorophs
What are the three sources of energy?
organic compounds, inorganic compounds, and light
In an organism uses organic compounds as a source of energy they are called ______
chemoorganotrophs
In an organism uses inorganic compounds as a source of energy they are called _______
chemolithotrophs
In energy is extracted from compounds in the presence of oxygen it is called an _________
aerobe
if energy is extracted from compounds in the absence of oxygen it is called an ________
anaerobe
if an organism uses light as a source of energy they are called _______
phototrophs
What is oxygenic photosynthesis? What kind of bacteria do this?
photosynthesis where oxygen is produces, cyanobacteria
what is anoxygenic photosynthesis?
photosynthesis where oxygen is not produced as a byproduct
What is free energy?
the energy available to do work
What does it mean in delta G is negative, what kind of reaction is this?
the reaction proceeds with the release of free energy, exergonic (catabolic reaction)
What happens during catabolic reactions?
things are broken down
What does it mean in delta G is positive, what kind of reaction is this?
the reaction requires energy to proceed, endergonic (anabolic reactions)
What happens during anabolic reactions?
things are made
Enzymes are usually _______ catalysts
protein
What is the function of enzymes?
lower activation energy for reactions to proceeds
a _________ lowers the activation energy of a reaction and thus increases the rate of a reaction
catalyst
What are some ways enzymes can lower activation energy and increase reaction rate?
align reactive groups
places strain on specific bonds
creates the correct microenvironment for reactants
Substrates are brought together at a specific site within the enzyme known as the _________
active site
What two models are there for enzyme/substrate interactions?
induced fit
lock and key
What are ribozymes
RNA molecules that act as catalysts
T/F enzymes are one and done and cannot be reused
False!!
what are 5 properties of enzymes?
increase reaction rates
can be recycled
much larger than substrates
can be regulated
affected by temperature and pH
Why is it important for enzymes to be regulated?
it is not ideal for all reactions to run all the time, energetically costly
What happens to enzymes when the temperature is too high?
they denature
many enzymes will contain small nonprotein molecules called ________ that participate in catalysis but are not themselves the substrates
cofactors
what are prosthetic groups?
cofactors that tend to be firmly attached and involve metal ions
what are coenzymes?
cofactors that are loosely attached and typically involve vitamins
