NEET MDS Shorts
353761
AnatomyThe nerve to masseter passes posterior to temporomandibular joint
606565
AnatomyGag reflex is lost due to paralysis IX Nerve
The pharyngeal branch of IX nerve supply the mucosa of pharynx
965969
AnatomyTemporalis muscle is inserted into Tip and medial surface of coronoid
471643
AnatomyThe parasympathetic fibers to pterygopalatine ganglion come from greater petrosal nerve
305080
AnatomyThe trigeminal ganglion lies on Anterior surface of petrous temporal bone near its apex in Meckel’s cave which is a space of dura mater
104500
AnatomyThese form specialized fibres of the heart and are supposed to be terminal filaments of bundle of His. They are placed beneath the endocardium and intervene between it and the myocardium.
866271
AnatomyThe largest resting membrane potential is observed in skeletal muscle.
Resting membrane potential (RMP) is the electrical potential difference across
the membrane of a cell when it is not undergoing an action potential or a
similar excitation. It is crucial for the functioning of excitable cells, such
as neurons and muscle cells, as it is the basis for the transmission of
electrical signals. The RMP is primarily determined by the concentration
gradients of ions across the cell membrane and the permeability of the membrane
to those ions.
In skeletal muscle cells, the resting membrane potential is typically around -90
millivolts (mV). This relatively high negative value is due to the higher
concentration of potassium ions (K+) inside the cell compared to the outside,
and the lower concentration of sodium ions (Na+) inside the cell compared to the
outside. The cell membrane is more permeable to K+ than to Na+ at rest, which
allows K+ to leak out through potassium channels and sets up the resting
membrane potential.
Smooth muscle cells, on the other hand, have a resting membrane potential that
is generally less negative than that of skeletal muscle cells. The typical RMP
in smooth muscle cells ranges from -40 to -70 mV, which is closer to the
threshold for depolarization and makes these cells more responsive to stimuli
that could cause contraction. The difference in RMP between smooth and skeletal
muscle is due to variations in ion channel expression and the activity of ion
pumps, which control the ionic composition of the intracellular and
extracellular environments.
To summarize:
1. Skeletal muscle cells have a resting membrane potential of approximately -90
mV.
2. Smooth muscle cells have a resting membrane potential that is generally more
positive than skeletal muscle cells, typically ranging from -40 to -70 mV.
531711
AnatomyCerebrospinal fluid (CSF) rhinorrhea occurs when there is a leak of CSF through the nasal cavity, often due to a defect in the skull base. The ethmoid bone is the most common site for such leaks because of its thin structure and proximity to the nasal cavity.