The correct answer for the question that is being presented above is this one:
(1) viruses only: capsid, envelope with glycoproteins, capsomere (core protein)
<span>(2) host cell only: ribosome
</span><span>(3) both: DNA, RNA, Protein</span>
Answer:
The correct answer will be option-
1. UV light strikes the skin and converts a steroid molecule into an inactive form of vitamin D.
2. Inactive vitamin D is transported to the liver where it is modified.
3. Vitamin D is activated under the influence of PTH.
4. Inactive, chemically altered vitamin D is transported to the kidneys.
Explanation:
Vitamin D is a fat-soluble metabolite which helps maintain the health of the bone by maintaining the calcium homeostasis.
The vitamin D is synthesized mainly in the liver and kidney from the biologically inactive precursor of vitamin D called ergocalciferol and Cholecalciferol.
The inactive vitamin is synthesized in the skin when the skin is exposed to UV rays. The UV rays convert the 7-dehydrocholesterol, a steroid molecule to Vitamin D3, This inactive vitamin is then transported to the liver where it is converted to 25-hydroxyvitamin D.
This vitamin D form is further metabolized in the kidney controlled and regulated by the Parathyroid glands.
Each DNA strand within the double helix is a long, linear molecule made of smaller units called nucleotides that form a chain. The chemical backbones of the double helix are made up of sugar and phosphate molecules that are connected by chemicals bonds, known as sugar phosphate backbones.
Hope this helps
Every cell in the body is enclosed by a cell (Plasma) membrane. The cell membrane separates the material outside the cell, extracellular, from the material inside the cell, intracellular. It maintains the integrity of a cell and controls passage of materials into and out of the cell.