Quiz 2 Flashcards
List the types of bonds from strongest to weakest
Ionic
Covalent
Metallic
List the intermolecular forces from strongest to weakest
Ion-dipole H bond Dipole-dipole Ion-induced dipole Dipole induced dipole Dispersion forces
Water has a high specific heat due to…
Hydrogen bonds
Delta G = delta H - TdeltaS
Understand how this works
Describe why lipids coaggregate in an aqueous solution in terms of entropy
The water forms a highly organized bonding pattern around lipids. When the lipids coaggregate, this organized bonding pattern is disrupted, thus increasing entropy
Release of ordered water ____ the formation of enzyme substrate complex
Favors
Adding solute (salt) to water, will increase or decrease the boiling point?
Decrease
What is the pH of a solution with [H+] = 0.01?
2
What is henderson hasslebach’s equation?
PH = pKa + log [A-]/[HA]
This means that when you have equal concentration of conjugate base and acid, pH = pKa
The pH of the body is controlled by what three systems?
Chemical acid-base buffering (phosphate in cells, bicarbonate in blood)
Respiratory center
Kidneys
Name the five nonessential amino acids
Aspartate Asparagine Alanine Glutamate Serine
Carbohydrates are mostly ___ enantiomer whereas amino acids are mostly ___
D
L
Name the non-polar amino acids
Glycine Alanine Proline Valine Leucine Isoleucine Methionine
Name the aromatic amino acids
Phenylalanine
Tyrosine
Tryptophan
Name the five polar-uncharged amino acids
Serine Threonine Cysteine Asparagine Glutamine
Name the three positively charged amino acids
Lysine
Arginine
Histidine
Name the two negatively charged amino acids
Aspartate
Glutamate
The aromatic amino acids can absorb UV light. Which is the best?
Tryptophan
What is the difference between cysteine and cystine?
Cysteine is an amino acid
Cystine are two cysteines put together by a DISULFIDE bond
Some amino acids are used in the body but are not incorporated into protein. Name two examples
Ornithine
Citrulline
What is a zwitterion?
A molecule that has opposite charges on it to make it neutral
The zwitterion exists at the isoelectric point called the pI. This is between…
.pK1 and pK2 (Or pK2 and pK3, there may be multiple possible zwitterions for an amino acid)
Amino acids are joined by ___ bonds which are formed by ____ reactions
Peptide
Condensation
The production of most plasma proteins occurs in the ____. What is the fetal counterpart of serum albumin?
Liver
Alpha-fetoprotein
Secondary structures of proteins can form…
Alpha helices or Beta sheets
In sickle cell anemia, what mutation occurs?
A glutamate is swapped out for a valine in hemoglobin. This will cause the red blood cells to change shape
True or false.. once a protein is denatured, it is permantely denatured
False… they may form back, but sometimes they comeback together the wrong way
The main neurotransmitter in the sympathetic nervous system is ___, the main NT in the parasympathetic is ___
Norepinephrine
Acetylcholine
Describe. What an axon hillock is
The final site where membrane potentials are propagated from synaptic inputs and summated before being transmitted to the axon for an AP
True or false… most neurons have just one axon
True
What are the functions of an astrocyte?
Regulates interstitial fluid composition
Replicates to occupy space of dying neurons
Helps form the blood brain barrier
What are some of the functions of the ependymal cells?
Lines the ventricles
Produces CSF
What are the functions of microglial cells?
These are like immune cells of the CNS
What are the functions of oligodendrocytes?
Myelinated and insulate CNS axons
True or false.. microglia cells are motile
True
What is another name for neurolemmocytes? Where are they found and what do they do?
Schwann cells
Found in PNS only
Wrap axons with myelin
The bonds found in the cell membranes of bacteria and eukaryotes are ____, whereas in archaea, its ___
Ester
Ether
True or false… anchored proteins are covalently bound to the membrane
True
True or false… associated membrane proteins do not directly attach to the cell membrane
True
True or false… different organelles in the cell has different lipid membrane compositions
True
True or false… you are likely to see more cholesterol in the golgi membrane than the plasma membrane
False.. the opposite
What enzyme in erythrocytes will convert CO2 to HCO3?
Carbonic anhydrase
Since cartilage is avascular, nutrients must diffuse through the ____ to feed the chondrocytes
Periochondrium
The perichondrium is composed of type ___ collagen.
1
What type of collagen is found in hyaline cartilage? What about fiibrocartilage?
What about elastic?
Hyaline = type 2 collagen Fibrocartilage = type 1 and 2
Elastic = type 2 and elastic
What is the role of chondroitin sulfate in cartilage?
Part of proteoglycans in ground substance. It has a negative charge and repels eachtohter, giving cartilage its squidgy-ness and resist compression
What is the weakest type of cartilage? Describe this cartilage
Hyaline cartilage (yet the most abundant)
Has a perichondrium
Spherical chondrocytes
What type of cartilage are fetal skeletons composed of?
Hyaline cartilage
Which type of cartilage forms rows of chondrocytes? Describe this type of cartilage
Fibrocartilage
Both 1 and 2 colleges
Strongest
**only type that lacks a perichondium
Highly compressible
Found in the knee and intervertebral discs
And pubic symphysis
Name 5 functions of bone
Support Protection Assisting movement Mineral homeostasis Blood cell production
Define apposition in reference to bone
Bone growth is accomplished by apposition by depositing bone on preexisting surfaces
What is the most abundant type of collagen found in bone?
Type one
True or false… osteoclasts are multinucleate
True
How doe osteoclasts absorb bone?
Attach via integrins to bone in locations called sealing zones
Osteoclasts pumps hydrogen ions against bone to dissolve the hydroxyapatite from collagen
PTH and vitamin D will stimulate osteoclasts to express their protein ___ ranks receptor to activate the osteoclasts
RANK
True or false calcium is stored in two forms in bone, the exchangeable form and stable form
True
PTH is secured by the ___ cells of the ____ and functions to ….
Chief
Parathyroid gland
Mobilizes calcium form bone to increase blood calcium levels
1,25 dihydroxycholecalciferol is formed from ____ and functions to ____
Vitamin D and the sun
Increases calcium absorption from the intestine
Increases calcium in bone
Calcitonin is secured by ___ of the ___ and functions to…
Parafollicular cells of the thyroid gland
Inhibits osteoclast activity, thus inhibiting bone resorption, and “toning down” blood calcium levels
Name three things that PTH will do when calcium levels are low
Calcium release from bone into blood
Calcium retention in the kidneys
Activation of vitamin D which increases calcium uptake in the gut
What is the name of the active form of vitamin D called?
Calcitrol (1,25 dihydroxycholecalcitrol)
What feedback inhibits PTH release?
Calcitrol
Name some things that calcitonin does
Inhibits calciu aborption in the intestines
Inhibits osteoclasts activity
Stimulates osteoblasts activity in bones indirectly
Inhibits renal absorption of calcium
Name four other hormones that have an impact on calcium regulation
Glucocorticoids
Growth hormone
Estrogens
Insulin
Defective bone matrix calcification due to vitamin D deficiencies is called ___
Osteomalacia (Rickets)
What is the difference between osteopetrosis and osteoporosis.
Osteopetrosis - osteoclasts dont work so bone density increases and becomes distorted
Osteoporosis - excess osteoclasts function resulting in loss of bone
What pump maintains electrochemical gradients?
Sodium potassium pump
What is the difference between the nernst equation and the goldman equation?
Nernst - equilibrium potential of an individual ion
Goldman - equilibrium potential for the entire plasma membrane
Passive current flow in a neuron will decay over distance because…
The cytoplasm is resistant
This will occur in neuronal cell bodies
The sodium potassium pump pumps ____ sodium out and ___ potassium in
3
2
The resting membrane potential is at ___ mv
-62
What occurs in the activation phase of an action potential?
Voltage gated sodium channels open to allow sodium to rush in. (At this same time, potassium channels are stimulated to open but do so much slower)
What occurs during the peak and falling phase of an AP?
Voltage sodium channels close and voltage potassium channels open to bring the membrane potential back down
What is the undershoot phase of an AP, shy is the refractory period significant?
It drops below its normal resting membrane potential. During this time, it cant do another AP. This ensures that the AP only goes one direction
What transporter in the recovery phase will bring the membrane potential back to normal?
Sodium potassium pump
True or false… the axon hillock is rich in voltage gated sodium channels and has a relatively low threshold
True
In regards to neurotransmitters, small molecules such as amino acids are synthesized in the ___ whereas neuropeptides are synthesized in the ___
Presynaptic terminal
Cell body (these can be released both pre and post synaptically)
The primary excitatory NT in the brain is…
Glutamate
Synaptic vesicles reside in three distinct pools. What are they?
Readily releasable pool
Recycling pool
Reserve pool
Explain the SNARE complex and how that allows vesicle release.
Synaptobrevin of the vesicle binds to syntaxin and SNAP25 of the membrane to dock. Then, calcium bind to synaptotagmin to cause the vesicle to exocytose
Describe the ultrafast synaptic vesicle cycle.
This is a way to reuptake NT. It occurs within about 5 seconds from uptake to being released again. This is the most likely cycle that occurs
What are the two NT receptor types? Describe them.
Ionotripic - Ligand binding will open ion channels to cause a direct depolarization (Na - excitatory) or hyperpolariztion (Cl or K - inhibitory)
metabotropic - G protein coupled intracellular signals, **relatively slow activation time, **prolonged signal duration
The location of the synaptic input matters. Describe this relationship
The closer the synapse is to the axon hillock, the more likely they are to trigger an AP
Postsynaptic potential summation depends on what two things
Location and frequency
Define spinal reflex
Sensory and motor loops that function independent of descending brain control
Describe long term potentiation
Occurs throughout adulthood (synapse pruning occurs during development)
The more you use a network, the greater the strength of connections, greater the number…. however if you dont use it, you lose it
In the somatosensory circuit, the second ordered neurons decussate at the level of ____. Nociception, however, decussates at the level of the ____
The medulla
Spinal cord
Somatosensory neurons are encapsulated by
Mechanoreceptor cells
True or false… a single neuron can innervate multiple mechanoreceptor types
False
Nociceptors and thermoreceptors have what kind of nerve endings?
Free nerve endings
Thermal nociceptors are separate from thermorecptors. They have ___ fibers. Mechanical nociceptors have ___ fibers. Polymodal nocicpetors have ___ fibers. Silent nocicpeors have ___ fibers
Thermal - alpha delta
Mechanical - alpha delta
Polymodal - C fibers (much slower, sense the pain after the sharp pain, sense thermal, mechanical, and chemical*)
Silent nociceptors - Alpha delta (respond to visceral disorder)
True or false… proinflammatory modulators such as thromboxanes and prostaglandins will sensitize nociceptors and directly activate nociceptors
True
How do silent nociceptors refer pain?
They synapse onto the same second ordered neurons as peripheral nociceptors
Explain how no descinding signaling must be involved in blocking pain?
Peripheral touch inhibits nociception. However, descending pathways do exist and are very effective (adrenaline)
Explain how opioids work
Opiates interact with CENTRAL pain receptors to block the transmission of nociceptive stimuli to the somatosensory cortex
