NEET MDS Shorts
374998
Prosthodonticsa properly designed rest on the lingual surface of a canine is preferred because it exerts less leverage against the tooth compared to a rest on the incisal surface (option 1). This is important for maintaining the integrity of the tooth and preventing potential damage or displacement.
349170
BiochemistryThe correct sulfur-containing amino acid among the options provided is:
1. Cystine
Explanation:
Amino acids are the building blocks of proteins, and they are characterized by
the presence of an amino group (-NH2) and a carboxyl group (-COOH). Some amino
acids also contain a side chain that is unique to each amino acid and determines
its chemical properties. Sulfur is an important element in the structure and
function of certain amino acids.
Cystine is a sulfur-containing amino acid, which is formed by the oxidation of
two cysteine molecules. Cysteine is the amino acid that contains a sulfur atom
in its side chain as a thiol group (-SH). When two cysteine residues are
adjacent in a polypeptide chain and the thiol groups react with each other, they
form a disulfide bond (-S-S-), resulting in the formation of cystine. This
disulfide bond is crucial for the tertiary structure of proteins, contributing
to their stability and function, particularly in the context of protein folding
and maintaining the integrity of protein domains.
The other options listed are not sulfur-containing amino acids:
2. Proline is an imino acid, meaning it contains an -NH group instead of an -NH2
group. Its side chain is a cyclic secondary amine and does not contain sulfur.
3. Arginine is a basic amino acid with a guanidino group in its side chain,
which is composed of nitrogen, carbon, and hydrogen atoms but no sulfur.
4. Isoleucine is a branched-chain amino acid, with a methyl group and an
isobutyl group on its side chain. It is a hydrophobic amino acid and does not
contain sulfur.
530707
Pedodontics
Explanation: Research indicates that the average caries experience in children aged 5 to 15 years is approximately 1 cavity per year. This statistic can vary based on factors such as diet, oral hygiene practices, and access to dental care, but on average, it is considered to be around 1 cavity per year during this developmental stage. This highlights the importance of preventive dental care and regular check-ups to manage and reduce the incidence of dental caries in children.
491939
PhysiologyGlomerular filtrate is essentially protein-free, allowing for the passage of water, electrolytes, and small molecules while retaining larger proteins in the bloodstream.
373392
General PathologyAscorbate (vitamin C) enhances the absorption of iron from the gastrointestinal tract, making it beneficial for individuals with iron deficiency anemia.
786381
PhysiologyThe majority of glucose reabsorption occurs in the proximal convoluted tubule, where glucose is actively transported back into the bloodstream.
325866
General MicrobiologyAntibodies neutralize exotoxins by binding to their protein components, preventing them from interacting with host cells and causing damage. This immune response is critical for protecting the host from the harmful effects of these toxins.
448437
EndodonticsExplanation:
One of the main disadvantages of glass bead sterilizers is that they are limited to sterilizing only small instruments due to the size of the sterilization chamber. Larger instruments cannot be effectively sterilized in this type of device.