midterms (1) Flashcards
● A change in matter from one
physical state to another physical
state
● Reversible change
● Involves a change in the phases of
matter
physical change
● Atoms rearrange to create a new
substance
● Irreversible change
● Involves a change in chemical
bonds
chemical change
Carbon dioxide in solid form (CO2)
dry ice
6 examples of physical change
● Freezing (liquid → solid)
● Melting or fusion (solid → liquid)
● Condensation (gas → liquid)
● Vaporization (liquid → gas)
● Sublimation (solid → gas)
● Deposition (gas → solid)
2 Ammonia gas (NH3)
Nitrogen gas (N2) + 3 Hydrogen gas (H2)
6 examples of chemical change
● Rusting of metals
● Combustion
● Metabolism of food
● Burning
● Color change
● Odor change
● Sum of all chemical reactions within a living organism
● Refers to a specific set of chemical reactions occurring
at the cellular level
○ e.g. sugar metabolism and fat metabolism
metabolism
2 key players in metabolism
enzymes and adenosine triphosphate
○ Proteins that act as catalyst to speed up reactions
○ Catalyze reactions for specific molecules called
enzymes, substrates
Substrates are transformed into new
substances called
products
A molecule that is a common energy source for all cells
adenosine triphosphate
A form of electromagnetic radiation that is visible to the eye. The energy of ___ is packaged in photons.
light energy
example of light energy
during photosynthesis
The transfer of kinetic energy from one object to another or from an energy source to an object.
heat energy
example of heat energy
organisms at constant body temperature
Energy possessed by an object due to its motion or its position relative to other objects.
mechanical
example of mechanical energy
muscle contraction such as walking
Potential energy stored in the electrons of
molecules. When bonds are broken and
rearranged, energy may be released.
chemical potential
example of chemical potential
The covalent bonds in organic molecules, such as glucose and ATP, store large amounts of energy. When bonds are broken in larger molecules to form smaller molecules, the energy that is released can be used to
drive cellular processes.
The movement of charge or the separation of charges can provide energy. Ion concentration across a membrane constitutes an electrochemical gradient, which is a source of potential energy.
electrical / ion gradient
example of electrical / ion gradient
During oxidative phosphorylation, an H+ gradient provides the energy to drive ATP synthesis.
Specific region of the surface of
enzyme molecule
active site
Material obtained as a result
from the chemical reaction
product
Chemical reactants where
enzymes bind to
substrates
Chemical reactions coordinated with each other and often occur in a series of steps
metabolic pathways
● Results in the breakdown of larger molecules into smaller ones
● Releases energy in the process
● Generally hydrolytic
○ Uses water
● Exergonic
○ Produce more energy than they consume
catabolic
● Results in the synthesis of larger molecules from smaller precursor molecules
● Uses energy in the process
● Often involve dehydration synthesis reactions
○ Releases water
● Endergonic
○ Consume more energy than they produce
anabolic
Comprises the metabolic reactions that a cell uses to get energy from food molecules and
release waste products
cellular respiration
Breakdown of glucose (compound with 6 carbon atoms) into two molecules of pyruvate (compound with 3 carbon atoms). Covalent bonds are broken and rearranged, and some of the energy released during the breakage of covalent bonds in glucose is harnessed to synthesize ATP.
glycolysis
