6. Cell Metabolism Flashcards
(23 cards)
Biosynthesis
the generation of natural products through enzymatic reactions (cellular metabolism)
Catalyst
a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.
Catalysis
the process of adding a catalyst to facilitate a reaction
Diffusion
process resulting from random motion of molecules by which there is a net flow of matter from a region of high concentration to a region of low concentration
Enzyme
proteins that help speed up metabolism, or the chemical reactions in our bodies
Hydrolysis
a common form of a chemical reaction where water is mostly used to break down the chemical bonds that exists between a particular substance
Substrate
an underlying substance or layer
Energy
capacity to cause change, especially to do work
Energy types
- Kinetic energy
- Thermal energy
- Chemical energy
- Potential energy
Kinetic energy
energy associated with the
relative motion of objects
Thermal energy
kinetic energy due to the
random motion of atoms and molecules (= heat)
Chemical energy
energy available in molecules for
release in a chemical reaction (= potential energy
Potential energy
energy that matter possesses as a
result of its location or spatial arrangemen
Photosynthesis
process that converts the electromagnetic energy in sunlight into chemical-bond energy in organic molecules
Cellular Respiration
a process that extracts energy from organic
molecules (food) by gradual oxidation
Gibb’s Free Energy (G)
amount of energy available in a molecule to do work in a system when the temperature and pressure are uniform
- measured in in kcal/mole
Delta G
free energy (C + D) - free energy (A +B)
Exergonic
A. reaction with negative change in free energy (ΔG<0)
Endergonic
A reaction with positive change in free energy (ΔG>0)
Spontaneous reactions
- exorgenic: release energy to its
surroundings - energetically favorable reactions
- has a lower free energy level (more stable)
- can release the free energy (potential energy) contained in bonds
Non-spontaneous reactions
- endergonic: they absorb energy from surroundings
- energetically unfavorable reactions
- has a higher free energy level than the substrate
- can store energy in molecules
Activated Carriers
- store energy either as a readily transferable chemical group or as readily transferable (“high
energy”) electrons - ATP, NADH and NADPH (most important)
ATP
- adenosine triphosphateà 1 adenosine (nitrogenous base) + 1 ribose (sugar) + 3 phosphate groups
- synthesized in an energetically unfavorable phosphorylation reaction, in
which a phosphate group is added to ADP (adenosine 5ʹ-diphosphate)
