Answer: Given below
Explanation: <em>The endosymbiotic theory states that some of the organelles in today's eukaryotic cells were once prokaryotic microbes. ... They eventually lost their cell wall and much of their DNA because they were not of benefit within the host cell. Mitochondria and chloroplasts cannot grow outside their host cell</em>
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You would want to know the weather forecast.
The answer would be “C,” a hypothesis. A conclusion occurs after the experiment—based on the hypothesis—while a constant is a scientific variable which remains unaffected throughout the duration of the experiment.
Small segments of dna that can move from one region of a dna molecule to another are transposable elements or "transposons"
Answer:
A. Natural killer (NK) cells are activated in response to interferons or macrophage and Major histocompatibility complex (MHC) and allows direct apoptosis of virus.
Viruses can invade NK cells by inhibiting MHC from reaching the cell surface. Using stimulating the inhibitory receptors and disrupting the activating receptors, viruses can avoid NK cells. MHC act as a ligand of inhibitory receptor, and when bind with inhibitory receptor allows damage to NK cells.
So, if i would be a virus i will use inhibitory receptors stimulation to avoid NK cells.
B. Bacteria are killed by phagocytic immune cell macrophages by engulfing them.
Bacteria avoid macrophages by escaping from phagosome before the lysosome fuses as lysosomal chemical kill the bacteria and some bacteria prevent acidification of the phagosome.
C. Parasites can avoid macrophages by modulating the host's cell cytoskeleton to block proper phagocytosis.
D. Bacteria can avoid dendritic cells by avoiding lysosomal degradation and prevent antigen presentation on MHC molecules that will modulate the entrance to DCs.
E. B cells are responsible for producing antibodies. Activation of B-cell depends on positive and negative signals transmitted through the B-cell receptor (BCR), so genetic polymorphisms and mutations affects the positive and negative signals. If mutation is done showing negative signal, B cell will not the activate and no antibodies will produce.
