Answer :
Surfactant deficiency due to undeveloped lungs (in premature infants) suggest respiratory distress in an infant, but would be less likely to be observed in an adult beacuse in adults , lungs are fully developed and lack of surfactant is less.
Explanation:
Respiratory distress syndrome is a type of neonatal disease of respiration ,caused by deficiency of the surfactant produced by type II alveolar cells in the lungs most commonly in premature infants.
Normally , the lungs of the fetus start the formation of the surfactant during the third trimester (26 weeks through labor and delivery ) but in the premature infants , the lungs are not totally developed , hence lack of surfactant production results in the respiratory distress syndrome charactarized by inflammation of the airways due to the lack of the surface tension lowring effect of the surfactant.
Answer:
float
Explanation:
like a balloon or an air filled raft
it helps them float
Gas vacuoles help bacteria in buoyancy and enable them to float at the desired depth. They do so by inflating and deflating the vesicles
byjus
Answer:
Repair mechanism for base cleavage (BER)
Explanation:
Repair by base cleavage (BER)
The altered bases are specifically recognized by glycosylases and removed, generating an AP site. The hole is filled by a DNA polymerase that takes the healthy strand as a template. This system arises not only by exposure to external agents, but also by the cell's own activity.
In case of damage in more than one nucleotide, repair by nucleotide excision (NER) is performed.
Nucleotide excision repair (NER)
The damaged area is recognized by UvrA and B, then A and B separate and UvrC enters which forms a complex with endonuclease activity with B. This enzyme cuts the T-dimer and the gap is filled by a DNA polymerase. There is also the TC-NER system (transcription-coupled nucleotide repair system). The alteration of these mechanisms gives rise to diseases such as: Xeroderma pigmentosum, Trichotiodystrophy or Cockayne Syndrome
Species A : 2N = 24, N = 12
Species B : 2n = 26, n = 13
During the hybridization N + n = 25