NEET MDS Shorts
69282
AnatomyThe external (lateral) pterygoid muscle has two primary functions: it assists in depressing the mandible (opening the mouth) and in moving the mandible forward (protrusion). This dual function distinguishes it from other muscles of mastication, which primarily elevate the mandible.
64743
AnatomyThe cricothyroid artery is a branch of the superior thyroid artery
98391
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.
14349
AnatomyTongue is protruded by Genioglossus
69072
Anatomy
Facial Artery: 1: True, it has cervical and facial portions. 2: True, it arises from the external carotid artery above the lingual artery. 3: True, it crosses the mandible at the anterior edge of the masseter muscle. 4: False, the cervical portion lies beneath the platysma,
but the facial portion does not exactly lie "superficial in the carotid
triangle"; rather, the facial artery travels more superficially than the
cervical part in its course.
68397
Anatomymuscle of the soft palate is not supplied by the pharyngeal plexus is Tensor veli palatine
94112
Anatomythe foramen ovale and foramen rotundum are both openings in the sphenoid bone. The foramen ovale is located posterior and lateral to the foramen rotundum. The foramen rotundum transmits the maxillary nerve (V2), while the foramen ovale transmits the mandibular nerve (V3) and the accessory meningeal artery.
47516
Anatomy
The 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.
74806
Anatomy
The spleen follows the long axes of ribs 9 to 11 and lies mostly posterior to the stomach, above the colon, and partly anterior to the kidney. It is attached to the stomach by a broad mesenterial band, the gastrosplemic ligament. Therefore, it is the most likely organ of the group to be pierced by a sharp object penetrating just above rib 10 at the posterior axillary line. Note that the pleural cavity, and possibly the lower part of the inferior lobe of the lung, would be pierced before the spleen. The ascending colon (choice 1) is on the wrong side (the right) to be penetrated by a sharp instrument piercing the left side. Most of the duodenum (choice 2) is positioned too far to the right to be affected by this injury. Even the third part of the duodenum, which runs from right to left, would still be out of harm's way. In addition, the duodenum lies at about levels L1 to L3, placing it too low to be injured in this case. The superior pole of the left kidney (choice 3) is bordered by the lower part of the spleen. However, it is crossed by rib 12 and usually does not extend above rib 11. It would probably be too low and medial to be injured in this case because this penetration is at the posterior axillary line.
24122
AnatomyBranches of Maxillary nerve are 1. Middle meningeal n. 2. zygomatic n. : zygomaticofacial, zygomaticotemporal 3.pterygopatine branches : orbital, post. sup. lat. nasal , medial septal, greater palatine, middle palatine , post. palatine 4. post. sup alveolar 5. Infraorbital middle sup. alveolar anterior sup. alveolar 6. Terminal lat. nasal inf. palpebral sup. labialis