🦴 Anatomy & aperol
In this body position, the patient lies face down with the anterior surface directed toward the table.
What is prone?
This passive transport mechanism moves a solute down its electrochemical gradient through a specific membrane carrier and can exhibit saturation kinetics.
What is facilitated diffusion?
The rapid increase in conductance of this ion produces the rising phase of a typical neuronal action potential.
What is Na⁺?
These two regions of the sarcomere become smaller during contraction, while the A band maintains a constant length.
What are the I band and H zone?
Addition of acetyl groups to histones generally produces this loosely packed, transcriptionally active form of chromatin.
What is euchromatin?
Surgeons can exploit these normally collapsed spaces between fascial layers to dissect along relatively avascular planes and minimize tissue damage.
What are potential spaces (or interfascial planes)?
This term describes the plateau reached when increasing solute concentration can no longer increase carrier-mediated transport because all available carriers are occupied.
What is the transport maximum (Tm)?
Increasing axon diameter decreases this, allowing local current to spread farther down an axon.
What is internal/axial resistance? (Ri)
Ca²⁺ binding to this regulatory protein causes tropomyosin to move away from myosin-binding sites on actin.
What is troponin C?
These small noncoding RNAs decrease gene expression by binding target mRNAs and promoting their degradation or inhibiting their translation.
What are microRNAs (miRNAs)?
Unlike a named peripheral nerve distribution, this sensory pattern reflects the territory supplied primarily by a single spinal cord segment.
What is a dermatome?
Impermeant charged proteins produce this equilibrium, in which diffusible ions become asymmetrically distributed while macroscopic electroneutrality is maintained.
What is Gibbs-Donnan equilibrium?
Myelination increases membrane resistance while decreasing this electrical property, allowing the membrane potential to change more rapidly.
What is membrane capacitance? (Cm)
During high-frequency skeletal muscle stimulation, insufficient time for Ca²⁺ reuptake into the SR produces this sustained state of contraction.
What is tetanus?
During apoptosis, this negatively charged phospholipid moves from the inner to the outer leaflet of the plasma membrane, marking the cell for phagocytosis.
What is phosphatidylserine?
Interruption of blood supply following a femoral neck fracture can cause death of bone tissue in the femoral head, a condition known by this name.
What is avascular necrosis?
This primary active transporter establishes the Na⁺ gradient that indirectly powers Na⁺-glucose cotransport and exchanges three Na⁺ out for two K⁺ in.
What is the Na⁺/K⁺ ATPase?
Lidocaine prevents action-potential propagation by blocking this class of ion channel.
What are voltage-gated Na⁺ channels?
In smooth muscle, the Ca²⁺-calmodulin complex activates this enzyme, which phosphorylates myosin light chains and permits contraction.
What is myosin light-chain kinase (MLCK)?
Dysregulation of this growth factor can promote tumor angiogenesis because its normal physiological role is stimulating new blood vessel formation.
What is VEGF?
This multiaxial synovial joint permits flexion, extension, abduction, adduction, circumduction, and axial rotation.
What is a ball-and-socket joint?
By inhibiting Na⁺/K⁺ ATPase, digoxin decreases the activity of this secondary transporter, causing intracellular Ca²⁺ to rise in cardiac myocytes.
What is the Na⁺/Ca²⁺ exchanger?
Severe hyperkalemia can paradoxically decrease excitability because persistent membrane depolarization places these into their inactivated state.
What are voltage-gated Na⁺ channels?
Active tension decreases when a skeletal muscle is stretched far beyond its optimal resting length because formation of these molecular interactions is reduced.
What are actin-myosin cross-bridges?
Hyperextensible skin, hypermobile joints, and tissue fragility point toward this group of inherited disorders involving abnormal collagen synthesis or structure.
What is Ehlers-Danlos syndrome?