Answer:
A
Explanation:
When these viruses insert their genome into the host cell, they usually have a reverse transcriptase enzyme that converts the RNA to DNA before it is integrated into the host genome. This is before the host cell machinery is hijacked to replicate the viruses components.
Cells, like bacteria and archaea, that do not have a nucleus in their cells have traditionally been called prokaryotes.
<h3>What are prokaryotic cells?</h3>
Prokaryotes are organisms whose cell (or cells) are characterized by the absence of a nucleus or any other membrane-bound organelles.
Prokaryotic cells are opposed to their eukaryotic counterparts that possess a membrane-bound nucleus that houses their genetic material (DNA).
Examples of prokaryotes are as follows:
Therefore, cells, like bacteria and archaea, that do not have a nucleus in their cells have traditionally been called prokaryotes.
Learn more about prokaryotes at: brainly.com/question/15329345
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You should mix
4µl of DNA sample and complete it with
96µl (100-4) of water.
You can figure this out by using
C1.V1 = C2.V2C1 = 250 <span>ng/μl (Sample Concentration)
</span>V1 = ?
(the necessary volume to take from the DNA sample)C2 = 10 <span>ng/μl (PCR concentration)
</span>V2 = 100 µl (total volume)
V1 =
=
=
4µl
For the water: 100µl (total volume) = 4µl + Water
Water volume = 96µl
Answer:
d. Fluoride becomes incorporated into the crystalline structure of teeth, making them less susceptible to decay
Explanation:
Dental caries results when cariogenic (caries-causing) bacteria metabolize carbohydrates or sugars present in the mouth for their energy needs, producing organic acids as byproducts, thus lowering the pH of the plaque biofilm.
The hydroxyapatite of tooth enamel is composed mainly of phosphate ions (PO₄³⁻) and calcium ions (Ca⁺). Under normal conditions, there is a stable equilibrium between the calcium and phosphate ions in saliva and the crystalline hydroxyapatite. At low pH (acidic conditions), there is a shift in equilibrium resulting in the dissolution of hydroxyapatite from tooth enamel, a process known as demineralization. A reverse process called remineralization (the process of incorporation of minerals in tooth enamel) occurs when the saliva, acting as a buffer elevates pH. When equilibrium is shifted to favor continued demineralization, dental caries results.
However, when fluoride is present in saliva, fluorapatite, rather than hydroxyapatite, forms during the remineralization process as fluoride ions replace hydroxyl groups in the formation of the apatite crystal lattice.
Fluorapatite is less soluble than hydroxyapatite making it more resistant to demineralization, even under conditions of low pH. Thus, fluoride acts as an effective anticaries agent.
Answer:
They suggested that the two continents where they were found could have been joined.
Explanation:
Hope this helps!（づ￣3￣）づ╭❤～
