Answer:
The best explanation if we observe an epithelial cell with chromosomes are visible and two cell nuclei is that the cell has just gone through telophase but not cytokinesis (option b).
Explanation:
A somatic cell, when found in mitosis, exhibits the chromosomes distributed in both poles and the outline of two nuclei in the telophase phase, just before cytokinesis.
In mitotic telophase:
- Chromatids, which are chromosomes, are found in the cell poles.
- It initiates the formation of the nucleus membrane.
- The chromosomes begin to turn into chromatin.
- Disappearance of the mitotic spindle, duplication of organelles and cytoplasmic invagination.
The division and differentiation of the nuclei in telophase is called karyokinesis. Later, cytokinesis occurs, where the daughter cells are separated.
The other options are not correct because:
<em> a and d. In the other phases described, </em><em><u>S and G1,</u></em><em> no chromosome distribution is observed at the poles.</em>
<em> c. A somatic cell does not experience </em><em><u>meiosis</u></em><em>.</em>
There is not enough evidence to support that <span>vitamin C aid in sore throat. But there is no harm too.
In the medical field, every treatment should be supported by evidence. This practice called evidence-based medicine. There is so much drug claim that actually wasn't supported by research and might be potentially doing more harm than benefit. Theory or argument about why it should work is not enough, you need to do a research to find the truth.</span>
<h2>Scurvy </h2>
Explanation:
(a) Collagen is the major structural component of cartilage,bones and tendons
- The basic unit of collagen is tropocollagen and each tropocollagen consists of three coiled left handed polypeptide chains called α chains
- Generally each α chain consists of a repeating tripeptide sequence called: G-X-Y
- Here G represents glycine; X represents proline and Y represents hydroxyproline
- Rigidity of collagen molecule is due to presence of proline and hydroxyproline
- Hydroxylation of proline is catalysed by prolyl hydroxylase enzyme which use ascorbate,α ketoglutarate and oxygen
- α ketoglutarate is oxidatively decarboxylated to form carbon dioxide and succinate
- Sequence of events leading from a dietary vitamin C deficiency to symptoms such as bruising and breakdown of supporting tissues includes: tissue levels of ascorbic acid is low; enzyme prolyl hydroxylase is inactive; proline is not hydroxylated; the triple helix is inadequately stabilized; collagen breaks down; defects in tissues that depend on collagen
; tissues that depend on collagen are subject to breakdown and bruising
(b) Sailors are no longer susceptible to scurvy because fresh fruits which are the source of vitamin C source are available now
British sailors called "limeys" to this day,this term reflects the British navy's use of limes
Answer:
Photosphere
Explanation:
The inner layers are the Core, Radiative Zone and Convection Zone. The outer layers are the Photosphere, the Chromosphere, the Transition Region and the Corona. IRIS will focus its investigation on the Chromosphere and Transition Region.
