Answer:
The theory of evolution was proposed by Charles Darwin and was first formulated in his book, "Origin of Species" in 1859. It focuses on the changes in species and populations over time
<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.
Scientists prove their hypothesis is true about Scientists can never "prove" their hypotheses are true, because some future experiment, possibly using new technology not currently available, might show the hypothesis to be false after all.
Answer:
strength: it provides raw material for plants and major component of food.
weaknesses: it increases earth's temperature and change the habitat.
Explanation:
The diagram shows the carbon cycle which is important cycle present on the earth. This carbon is present in carbondioxide form which is used as a raw material by plants in order to make their own food. This carbon is also present in different organic compounds. When its concentration increases in the atmosphere, the temperature of the atmosphere increases and many areas are not suitable to live for many plants and animals.
