<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
Kingdom, phylum, class, order, family, genus, and species is the classification chart levels in order from most broad to least.
The nucleus controls the activities within a eukaryotic cell
Answer: diffusion
Explanation:
Diffusion is the over all movement of molecules from one region where it is in high concentration to another another region where it is in lower concentration.
This movement continues until the concentration of both regions are equal. Smaller non polar molecules are able to diffuse through the lipid bilayer of the membrane .
Movement through the membrane is dependent on the concentration gradient, that is the difference in concentration between the two areas.
It is also dependent on the size of the molecule
