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three weak hydrogen bonds are between guanine and cytosine bonds</span>
The way I'm interpreting this is that what type of bound are these? And yes share electrons in various bonds can share electrons lose and gain, these all sounds like covalent bonds and ionic and hydrogen bounds are from.single to double and to triple bounds.
A new island is formed from a volcanic eruption is an event that lead to speciation.
<h3>What is speciation?</h3>
Speciation is the evolutionary process in which in populations of organisms come to being or evolve to become distinct species. The biologist Orator F. Cook made some Discovery and term it speciation in 1906when he performed experiment on cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within lineages.
Therefore, A new island is formed from a volcanic eruption is an event that lead to speciation.
Learn more about speciation from the link below.
brainly.com/question/2113835
An example of an alternate path in the rock cycle could be sedimentary rock goes through melting and becomes magma.
<span>Cytotoxic t-cell subpopulations are specialized to combat intracellular pathogens, whereas helper t-cell subpopulations are specialized to combat extracellular pathogens.
</span>Cytotoxic t-cell are CD8+ cells. Cytotoxic t-cell uses granzymes to <span>kill </span><span>intracellular bacteria, that lives in the cytosol such as viruses. They identify the pathogen forgein peptids that are bounded to MHC-I on the cell surface.
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cd4+ T helper (Th) cells include Th1, Th2, and Th17 cells. They contribute to aliergic reactions and fighting extracellular parasites.