NEET MDS Shorts
31397
Oral PathologyOral lesions on the tongue are commonly caused by a deficiency of Niacin (Vitamin B3).
16601
Physiology
Answer: 1) Dilatation (mydriasis)
Explanation: Norepinephrine acts on alpha-adrenergic receptors in the pupillary dilator muscles, leading to pupil dilation. This is a component of the sympathetic nervous system's response to stress, which also includes pupil dilatation mediated by epinephrine.
78167
NEETMDS
Each enamel rod is built up of segments separated by dark lines that give it a striated appearance, which becomes more visible in ground sections. The rods are segmented because the enamel matrix is formed in a rhythmic manner. The length of each segment is about 4 µm.
12639
Physiology
The axons of sensory neurons from the dorsal root ganglion can follow three routes: forming spinal reflexes by synapsing with motor neurons, ascending to the brainstem for conscious perception, or relaying through the reticular formation and thalamus for general arousal.
14818
Oral PathologyThe oral lesion of warty dsykeratoma is described as a small whitish area of the mucosa with a central depression
92155
ProsthodonticsTreatment of choice for a patient with a maxillary complete denture with severe bilateral tuberosity undercuts is to remove the tissue on only one side if possible.
43715
Physiology
The decreased CO2 concentration in the airways can cause bronchoconstriction,
which is the constriction of the airways. This is the correct answer among the
options provided. Here is the detailed explanation:
CO2 (carbon dioxide) is an important regulator of bronchial tone. It acts
primarily through the chemoreceptors located in the carotid body and the
medullary centers of the brain, which respond to changes in the partial pressure
of CO2 in the arterial blood (PaCO2). When the concentration of CO2 in the
airways decreases, it leads to a reduction in the PaCO2. This drop in PaCO2 is
detected by the central nervous system, which then responds to maintain
homeostasis.
The body normally adjusts the diameter of the airways to ensure proper gas
exchange and ventilation. When PaCO2 levels decrease, the respiratory center in
the brain perceives this as an increase in pH (alkalosis), which can be
detrimental to the body's overall homeostasis. To counteract this, the
respiratory center initiates a reflex that can lead to bronchoconstriction. This
reflex is known as the Hering-Breuer reflex. The vagus nerve, which innervates
the airway smooth muscles, is activated by the increase in pH, causing the
release of acetylcholine and other bronchoconstrictive substances. This, in
turn, results in the contraction of the smooth muscles surrounding the
bronchioles, leading to a narrowing of the airway diameter.
Therefore, the correct answer is 2. Constriction of airways.
This response is essential in the regulation of respiration and maintaining the
optimal pH balance in the body. It is part of the body's complex system to
ensure that oxygen and carbon dioxide are properly exchanged in the lungs and
that the blood remains at a slightly alkaline pH level. However, in individuals
with certain respiratory conditions such as asthma or chronic obstructive
pulmonary disease (COPD), bronchoconstriction can exacerbate their symptoms and
potentially lead to respiratory distress.
40689
Radiology
The traditional darkroom processing sequence for radiographs is as follows:
94045
RadiologyIn the TMJ view, the central X-ray passes through the sigmoid notch in the infracranial view.
59087
General MedicineAlpha antitrypism deficiency causes panacinar emphysema