Answer:
The correct answer is: d. REs activity is best preserved by freezing the RE and thawing it out for brief periods of time as needed.
Explanation:
- Restriction enzymes can be defined as endonucleases that can recognize specific nucleotide sequence in a DNA (Deoxyribonucleic acid) sequence and cause breakage of phosphodiester bond in the DNA at the target site. Hence, it has the capacity of cleaving a DNA sequence.
- These are made up of proteins which are required to be present in the accurately folded conformation in order to function.
- Any form of alteration in the three-dimensional structure of the protein induced due to physical, chemical, mechanical or physiological factors can cause denaturation of the protein which in turn can render the protein non-functional.
- Freezing of restriction enzymes (REs) directly without the use of glycerol will cause the movement of water molecules within the proteins as well layering of water molecules on the protein surface.
- At low temperature these water molecules change to ice crystals which can alter the conformation of the protein or can cause breakage of peptide bonds in the proteins by physical force.
- This can cause the protein to get denatured and hence non-functional.
- Hence, it is never advisable to preserve REs by freezing directly without glycerol.
- Glycerol forms a layer around the protein molecules and prevents the protein molecules from coming into direct contact with the water molecules and hence prevents protein denaturation.
Answer:
The effects of climate change may be associated with the increased incidence of <em>V. vulnificus</em> infection
Explanation:
<em>Vibrio vulnificus</em> is a harmful bacterium that causes a serious disease due to eating contaminated seafood, which is the main cause of seafood-related deaths in the USA. <em>V. vulnificus</em> is naturally present in the flora of coastal waters around the world and this bacterium has been isolated from a variety of seafood (e.g.., fish, oysters, shrimp, etc). Epidemiologic studies have shown that the incidence of <em>V. vulnificus</em> infection has increased dramatically since 1996. During this same period, climate change has been responsible for the increase in salinity and temperature of the coastal waters (i.e., the natural habitat of this bacterium). In consequence, it is reasonable to suppose that the change in climatic conditions may be associated with the increased incidence of <em>V. vulnificus</em> infection.
They do not have a cell wall because only plant cells have that. The plant cells have that to help with the process for creating the green color. The animal cells, instead, they have a cell membrane.
I thought it was savannah but grasslands could be it too.
<span>These organisms obtain energy and carbon from the physical environment and use it to produce their food. They make sugars and other compounds using sunlight as a source of energy and carbon dioxide as a carbon source. The evolutionary advantages for these organisms are the periodic renewal of atmospheric O2 for all living beings. The production of organic matter and food webs of any ecosystem. Without them, there is an extinction of all living organisms due to the non-renewal of atmospheric O2 and the excessive accumulation of CO2 in the atmosphere.</span>
