Answer: a tiny muscle connected to each hair follicle and the skin. When it contracts it causes the hair to stand erect, and a "goosebump" forms on the skin.
It’s actually bacterial DNA
photosynthesis as a whole takes place in the organelle called chloroplast but light reaction takes place in the chloroplast stroma
<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.
For him they were just discrete physical units of inheritance. Johanson coined the term "gene" and people started calling them genes. Today for us these factors are parts of DNA, the base sequences that carry the biological information to determine a trait. Mendel factors are alleles of genes.
