Answer:
Surface area to volume ratio, in simple means the size of surface area to the volume of substance that can pass through it at a particular time.
Amoeba and some bacterias are flat and have large surface area to volume ratio. So the diffusion rate is very high due to large surface area.
Where as humans have small surface area: volume so diffusion is very slow or does not take place at all.
Explanation:
As the ratio gets smaller, it takes longer for items to diffuse.
Explanation:
When the cell increases in size, the volume increases faster than the surface area, because volume is cubed where surface area is squared.
When there is more volume and less surface area, diffusion takes longer and is less effective. This is because there is a greater area that needs to receive the substance being diffused, but less area for that substance to actually enter the cell.
this is actually why cells divide. When they become too large and it takes too long for them to transport materials across the cell, they lose efficiency and divide in half to raise the surface area to volume ratio.
I HOPE TGIS HELPS PKEASE MARK ME AS BRAINLIEST
Plicae, villi and microvilli increase the surface area for he absorption of nutrients
Answer: a) substrate and cofactors b) covalent modification
Explanation:
Metabolic pathways involve all the chemical processes takes place in the enviornment or in an organisms.The metabolic pathways are controlled through the catalytic activities of enzymes.
The availability of enzyme is regulated by substrate and cofactors present in enzyme and enzyme activity is commonly regulated via covalent modification.
Enzymes are highly selective in nature and bind to a specific substarte only. The active site in enzyme binds with the substrate to form enzyme substrate complex. Coactors assist the enzyme activity, without cofactor enzyme can not perform its activity.
Hence enzyme availibility is regulated by substrate and cofactors regulates.
Covalent modifications regulates activity of enzyme as it involves addition and removal of chemical group to synthesis required protein. It can change the chemical properties of the site by targeting one or multiple amino acid.
Thus the correct answer is a) substrate and cofactors b) covalent modification
Answer:
i will try my best here goes
Explanation:
i believe it is O Cytokinesis in an animal cell because there is the formation of a cleavage furrow.
The most important idea is that the genetic material of any organism must be able to accurately replicate itself at least every generation (or for multicellular organisms at each cell division).
Base pairing (A-T or U and C-G)allows DNA and RNA (eg in polio virus, see Wikipedia page on RNA dependent RNA polymerase) to create a copy of themselves, when the appropriate enzymes are present. Proteins have no way of making a copy of themselves.
Stability is probably the main reason DNA is the most common genetic material. DNA has no enzymatic activity and was probably selected for to maintain the integrity of the genetic material (rather than having to perform a function for the cell/virus, during which it may be destroyed). The double helix structure also protects its integrity, and proofreading enzymes have also evolved which correct most of the mistakes made at DNA replication. RNA viruses don't have this mechanism- which could be said to be an advantage (as they can rapidly change and therefore avoid their hosts' immune systems), however in non-parasitic organisms most mutations in a gene would lead to a loss of an essential function and the extinction of that genome.
I don't think either of these reasons are relevant, but I think the main reasons retroviruses convert their RNA to DNA are so they can use the host cell's replication machinery (this was they do not need to encode as many genes), and secondly they need avoid the antiviral mechanisms of the cell, which would destroy any double stranded RNA molecules found (even if the virus was single stranded, dsRNA would have to be produced at replication).
