MCAT Flashcards
The _____ of a wave is directly proportional to its _____, but inversely proportional to its _____
The energy of a wave is directly proportional to its frequency, but inversely proportional to its wavelength

Define: Doppler Effect and its Result
An increase (or decrease) in the frequency of sound, light, or other waves as the source and observer move toward (or away from) each other.
The effect causes the sudden change in pitch noticeable in a passing siren.
Shifts frequency, not intensity, so cannot dampen sounds

________does not change when the wave travels from one medium to another!
Frequency does not change when the wave travels from one medium to another!
Why doesn’t _____ change when going through different mediums?
What happens to frequency?
What happens to wavelength?
What happens to speed of wave?
When waves travel from one medium to another the frequency never changes.
As waves travel into the denser medium, they slow down and wavelength decreases. Part of the wave travels faster for longer causing the wave to turn.
The wave is slower but the wavelength is shorter meaning frequency remains the same.

What is Interference? (Waves)
What are the different types?
What do the different types look like?
The combination of 2 or more waves. Can be constructive or destructive

What is Constructive Interference?
Interference: The combination of 2 or more waves.
When the waves are in-phase (crest meets crest, trough meet trough), this is Constructive Interference.

What is destructive interference?
When the waves are out-of-phase (crest meets trough, trough meets crest), this is destructive interference and the amplitude (maximum displacement of a wave from its equilibrium) of the resultant wave is equal to the difference between the 2 individual amplitudes
Decreases amplitude, therefore energy, and thus loudness

What is the relationship between amplification, energy, and frequency?
The amplitude, or vertical height, of a wave is defined as half the peak-to-trough height; as the amplitude of a wave with a given frequency increases, so does its energy

Define Wavelength
The distance between two corresponding points in a wave—between the midpoints of two peaks, for example, or two troughs—is the wavelength (λ)

Define frequency, what are its units?
The frequency (ν) of a wave is the number of oscillations that pass a particular point in a given period of time. The usual units are oscillations per second (1/s = s−1), which in the SI system is called the hertz (Hz)

Define: Amplification
A result of constructive interference

What changes in a molecule would you expect in a Nucleophilic Addition?
would expect to see a pi bond in the molecule break in order to form two new sigma bonds.
What is Hydrolysis? What are 3 common types?
Hydrolysis - hydrolysis is a chemical reaction in which water is used to break down the bonds of a particular substance.
Opposite of condensation (combination of 2 molecules that results in the release of H2O).
Salts: Hydrolysis occurs when salt from a weak base or acid dissolves in liquid. When this occurs, water spontaneously ionizes into hydroxide anions and hydronium cations. This is the most common type of hydrolysis.
Acid: Water can act as an acid or a base, according to the Bronsted-Lowry acid theory. In this case, the water molecule would give away a proton. Perhaps the oldest commercially-practiced example of this type of hydrolysis is saponification, the formation of soap.
Base: This reaction is very similar to the hydrolysis for base dissociation. Again, on a practical note, a base that often dissociates in water is ammonia.

Define: Saponification
Saponification - describes basic hydrolysis of ester bonds. Typlcally a triglyceride

What would you expect to see in an oxidation reaction?
Oxidation - more oxygen appears in molecule
Oxidation: gain oxygen, lose hydrogen, lose e-
What is a dehydration reaction?
Dehydration - the removal of water from a molecule
What is a lipase? What is its role?
Lipase - an enzyme that breaks down fats (which contain 3 esters)
A lipase is any enzyme that catalyzes the hydrolysis of fats. Lipases are a subclass of the esterases. Lipases perform essential roles in digestion, transport and processing of dietary lipids in most, if not all, living organisms.

What is the most common biomolecule is an amide present in?
Amides - Functional groups present in proteins

What is a hemiacetal?
What common biomolecule is it found in?
Hemiacetals - functional groups present in sugars

What common biomolecules are ethers found in?
Ethers - not largely important for biological molecules

Define: Gauge Pressure
The pressure relative to atmospheric pressure
Positive for pressures above atmospheric pressure
Negative for pressures below atmospheric pressure
Atmospheric pressure adds to pressure of any fluid not enclosed in a rigid containers. Happens because of Pascal’s Principle
Define: Absolute Pressure
Sum of gauge pressure and atmospheric pressure
Pabs = Pg (gauge) + Patm (atmosphere)
Can never be negative
Because fluids push rather than pull, the lowest absolute pressure can be is zero.
Define: Ambient Pressure
Pressure of the surrounding medium (gas or liquid) of an object
Define: Systolic Pressure
Maximum Blood Pressure







