Exam 1 Flashcards
T/F
Covalent bonds are always stronger than ionic bonds.
False
Which type of bonds are often irreversible by biological systems?
Covalent
Van der Waals forces are usually associated with
Lipid bonding
Disulfide bridges are examples of ______ bonding and are found in ____.
Covalent; DNA
Electrostatic forces are an example of ____ bonding.
Ionic
T/F
Hydrogen bonding is weaker than ionic bonds.
True
T/F
Hydrophobic interactions are generally strong.
False; they’re weak
What bond/interactions exist between lipophilic drugs and lipid component of membrane/receptor?
Hydrophobic
Most drugs are _____.
Weak bases
Diffusion thru cell membrane requires _____.
Lipid solubility
T/F
Drugs that are proteins are best given by mouth.
False; stomach acid denatures proteins
Pharmacodynamic examines the effect the ____ has on the ____.
How the drug affects the body
Pharmacodynamics relates ____ and ____.
Drug concentration & its effect.
Pharmacokinetics relate ____ and ____.
Dose & tissue concentration.
T/F
All drugs can be mathematically modeled to predict absorption and metabolism.
False
Acidic Rx in acidic conditions will….
Cross the GI mucosa and enters bloodstream.
Basic drugs are best absorbed ____.
In lower GI tract; below beginning of SM intestine
T/F
Drugs with high affinity always give high effect.
False; high affinity does not guarantee high effect. It can bind without producing effects.
Affinity
Level of attraction between compound and receptor.
High affinity + low intrinsic activity
Competitive antagonist
must have affinity b/c it binds
little/no intrinsic activity b/c it does not stimulate receptor very well
What aspect contributes to higher side effects?
Low specificity
Low affinity drugs have a (higher/lower) KD than high affinity drugs.
Higher
High affinity drugs occupy _____ receptors at ____ concentrations.
High affinity occupies many receptors at low concentrations.
More potent drugs have (higher/lower) EC50.
Lower EC50
EC50 = concentration that gives half of max effect
Higher potency = lower [ ] needed
Which is more potent?
Which has higher efficacy?
A is more potent (more to the left)
B has higher efficacy (reaches higher point on y axis)
(T/F)
The action of an agonist at a receptor can also be a side effect.
True
Which part of the neuron generates the action potential?
Axon hillock
(T/F)
Drug receptors can be found in the cytoplasm and nuclear envelope.
True
Digitalis works by
Inhibiting Na/K/ATPase pump of myocytes
What are some types of nonspecific acting drugs?
Carbon Monoxide (binds to Hgb)
Alkalinizing drugs
Acidifying drugs
Mannitol (pulls water into urine)
Anesthetics mechanism of action
Most effects are receptor mediated.
Alters membrane fluidity, making it less gelatinous and losing membrane pump function.
Aminoglycoside antibiotics act on…
What are some examples of aminoglycoside meds?
The ribosome
Impairs bacterial protein production.
gentamicin, amikacin, tobramycin, neomycin, and streptomycin
Neuroleptics act in ____ and are used as ____
The CNS
Tranquilizers
(T/F)
All drugs exert their effects via receptor-mediated response.
False
Mannitol, methyl cellulose and dextrans are non-receptor mediated drugs.
_____ is/are responsible for transduction of biologic signals.
Receptors
(T/F)
Enzymes can be drug receptors.
True
What drug acts on nucleic acids?
Actinomycin D
Altering the ligand structure will affect its
Affinity and/or intrinsic activity (due to required fit for binding site)
Examples of drugs that do not act on receptors
Some anesthetics, hypnotics, and sedatives
Alcohols
Osmotically-active drugs
Acidifying/alkalinizing agents
Antiseptics
Mannitol
Methyl cellulose
Dextrans
Nonspecific receptors require ____ drug concentrations to produce effect. Specific receptors require ____ .
Nonspecific receptors need high concentrations of drug for effect (milimoles or moles).
Specific needs only low concentration (nano to mili moles).
When active, _____ converts ATP to cAMP.
Adenylate cyclase
_____________ function as pores, allowing passage of Na into smooth muscle.
Electrotonic gap junctions
(T/F)
When part of a motor unit, a muscle fiber can be stimulated individually.
False; they are stimulated as a unit.
Propagation vs. diffusion of a charge down the axon
Diffusion is less effective, as the charge would be reduced once it reaches the terminal.
Na coming into the neuron _____ voltage.
Increases
When K exits the neuron, it restores the more ____ charge.
Negative
Local anesthetics work by
Blocking Na channels in the neuron, preventing transmission of the impulse down the axon.
Noncompetitive antagonism on a response curve will show as
Flattening curve as more inhibitor is added
Positive allosterism is seen on a response curve as
Left shift, similar to increasing potency
What happens in positive allosterism?
The ligand increases receptor affinity for agonist.
What happens in negative allosterism?
Inhibitor decreases affinity for agonist to bind to receptor.
Response curve looks similar to non-competitive antagonism; curve flattens as more inhibitor is added.
Fat receives less of what supply?
Water and blood
(T/F)
The constituents of ICF and ECF are identical, but vary in quantity.
True
Proteins are more abundant in the (ICF/ECF).
ICF
Which are mostly in ECF? Which are mostly in ICF?
K
Cl
Na
ECF: Na, Cl
ICF: K
ECF is regulated by the ____
Kidneys
(T/F)
All cells have a nucleus.
False
RBCs do not have a nucleus.
What are the most abundant constituents of lipid membranes?
Proteins and phospholipids
How does water enter the cell?
Passive diffusion & aquaporins (proteins that fxn as water channels)
T/F
Glucose can readily enter the cell.
False
The membrane is nearly impermeable to ions and glucose.
T/F
Steroids can readily pass thru the cell membrane.
True
Fat-soluble substances, such as steroids readily cross the membrane.
Gases such as O, CO2, & N pass thru the membrane easily via _____
Diffusion
Glucose and amino acids enter the cell thru _______.
Facilitated diffusion
How can a cell uptake material without it actually passing thru the membrane?
Endocytosis
_____ ions are required to eject neurotransmitters via ____.
Calcium
Exocytosis
T/F
The goal of the Na/K/ATPase pump is to reduce the number of ions in the ICF.
True
Must balance the large amount of protein and other intracellular stuff
Malignant hyperthermia is linked to a defect in the gene encoding proteins for the ______ receptor, the primary receptor for releasing Ca from the sarcoplasmic reticulum.
Ryanodine
The Na/K/ATPase pump, pumps Na and K _____ their gradient.
Against
Requires ATP = active transport = against gradient
What is the primary transmembrane transporter for drugs across the BBB?
P-glycoprotein
When going against the concentration gradient, a _____ is often needed, which requires ____.
Proteins are often needed, which require ATP
Genetic defects in aquaporins may cause which diseases?
Congenital cataracts
Nephrogenic diabetes insipidus
T/F
The nucleus of an egg cell has 46 chromosomes.
False
All nucleus have 46 chromosomes, except eggs which have 23
Histones
Proteins that cover DNA and regulate transcription
What passes thru nuclear pores?
Large mlcls, such as proteins, DNA & RNA
What does the nucleolus do?
Synthesize ribosomes
________ coordinates movement of chromosomes during cell division.
Centrioles
What happens to noncoding genes?
They are transcribed to RNA but not translated into proteins.
Mitochondria contain…..
Enzymes and substrates of the Krebs cycle and ETC.
Oxidative phosphorylation occurs ______.
In the mitochondria
Where are the protons generated through the ETC?
Between the 2 lipid membranes of the mitochondria
In the ETC, what drives the conversion from ADP to ATP?
The movement of protons back into the mitochondrial matrix through the inner membrane.
moves: intermembrane space –> thru inner membrane –> mitochondrial matrix
What enzyme converts ADP to ATP?
ATP synthase
T/F
Mitochondria are always inherited from the mother.
True
Sperm have no mitochondria
Ribosomes are mainly composed of ____.
RNA
T/F
The rough endoplasmic reticulum lacks ribosomes.
False
The smooth ER lacks ribosomes
The sarcoplasmic reticulum is a reservoir for ___.
Calcium
Proteins made in the rough ER are sent to _______ where they are stored in __________.
Golgi apparatus
Secretory vesicles
_____ vesicles continuously secrete their content. ____ vesicles release their content when a trigger signal is received.
Exocytotic vesicles continuously secrete.
Secretory vesicles secrete when signaled.
What makes lysosomes?
Golgi apparatus
Regulated secretion in anesthesia includes
Neurotransmitter release
Studies what the body does to a drug.
Pharmacokinetics
Studies what the drug does to the body.
Pharmacodynamics
T/F
Different patients can have similar plasma concentrations of a drug but vary in response.
True
Chiral
A center with 3-dimensional asymmetry
T/F
Enantiomers can be superimposed on each other if rotated correctly.
False
Enantiomers are non-superimposable mirror images
A D enantiomer rotates light in which direction? Is it negative or positive?
D config:
Clockwise
+
Dextrorotatory
An L enantiomer rotates light in which direction? Is it negative or positive?
L config:
Counterclockwise
-
Levorotatory
Racemic mixture
Contains equal parts of two enantiomers. They cancel each other out. No rotation of light.
T/F
Enantiomers usually have identical pharmacological activity.
False
They can have different absorption, distribution, potency, clearance and toxicity.
T/F
Enantiomers can antagonize each other’s effects.
True
T/F
Systemic therapy can be achieved through topical administration.
True
transdermal patches and some creams/ointments can achieve this
T/F
Aerosols penetrate completely to the alveoli.
False
Aerosols are used for localized airway and bronchial tissue.
Gaseous and volatile agents penetrate completely to the alveoli.
What is one challenge with rectal administration?
There is an unpredictable volume of water, making absorption unpredictable.
T/F
First pass metabolism can be avoided with rectal administration.
True
Drugs absorbed in the lower intestines do not go directly to liver before the heart.
Which route of administration has no absorptive phase?
IV
Why give a drug through an artery?
give high concentration to a target tissue
chemo & diagnostics
fewer local irritations
Epidural injections are made inside ____ but external to ______.
inside the bony spine but external to the dura matter
Max volume for IM injection
5 ml
Which absorbs faster into systemic circulation? SubQ or IM?
IM
Depot injection
Offers slow absorption of the agent over a prolonged period.
Long term therapy with fewer doses.
Usually prepared in oil.
Most drugs cross tissue membranes by _____.
simple lipid diffusion
What happens with drugs that are too lipid soluble?
Cannot move out of the membrane once it enters
Lipid solubility to water solubility
“oil-to-water partition coefficient”
Predicts how well a drug will cross biological membranes.
Measures the [ ] of each.
Octanol is used b/c its similar to biological membranes.
Larger value = more lipid soluble
T/F
Amino acids are neutral at biological pH.
False
they are charged
Transport molecules are proteins and can be found ____.
in cell membranes
Gases and volatile agents must possess ____ to cross from the alveoli into the blood?
some blood & lipid solubility
The blood-to-gas partition coefficient uses the _____ of the agent in each component.
partial pressure
What is the driving force to bring gases and volatile agents in the blood?
The higher initial partial pressure of a gas/volatile agent at the alveoli is the driving force for the movement of the molecules into the blood until equilibrium is reached.
Tissue-to-blood partition coefficient
Relative solubility of a drug in a tissue compared with the blood.
Determines what tissues Rx enters and to what extent.
T/F
Tissue-to-blood partition coefficient can be used to determine effect.
False
Some drugs may enter tissue to a small extent but have great effect.
An acidic compound is uncharged in the (protonated/unprotonated) form.
Acidic:
uncharged when protonated
A basic compound is uncharged in the (protonated/unprotonated) form.
Basic:
uncharged when unprotonated
T/F
Procaine has a slower onset than Lidocaine
True
Lidocaine pKa 7.9
Procaine pKa 8.9
With procaine, it takes longer for the ionized molecules to become unionized.
A weak base drug in acidic conditions will be (ionized/not ionized).
Ionized
T/F
Onset of a drug is affected by pKa.
True
T/F
The thickness of a membrane does not affect rate of diffusion.
False
Thicker membrane = slower diffusion
T/F
Diffusion rate can increase if there is a large difference in drug concentrations from one side of the membrane to the other.
True
T/F
Drugs that are weak bases absorb well in the stomach.
False
Solid dosage forms, such as tablets and capsules must undergo ____ before being absorbed.
dissolution
the process by which solid dosage form breaks into individual molecules/small absorbable particles
Acid labile
Easily denatured by acid.
Enteric coating used to protect from stomach so it can be dissolved in small intestine.
Acidic drugs in acidic conditions will be (ionized/not ionized).
Not ionized
Which type of drug will absorb well in the stomach? Weak acid or weak base?
Weak acid drugs absorb well in the stomach.
Passive diffusion requires a drug to be ___.
Passive diffusion requires a drug to be in a lipid soluble form.
Most drugs are best absorbed in ______.
Most drugs are best absorbed in the small intestine.
What feature of the small intestine increases absorption? What feature might make absorption more difficult?
Microvilli increase the surface area for absorption.
The glycocalyx layer keeps very lipid-soluble drugs from entering epithelium (Large octanol-to-buffer values)
Epithelial endocytosis
In GI tract, highly lipid-soluble drugs can bind to fats and be absorbed this way as opposed to passive diffusion.