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between 1347 and 1350, the bubonic plague killed nearly half of europeans. scientists have discovered that about 10% of the modern descendants of those who survived the plague have a resistance to infection by the human immunodeficiency virus (hiv).
which hypothesis bestexplains this occurrence?
a. the individuals who survived were not exposed to the plague which enabled their descendants to be resistant to hiv.
b. the individuals who survived the plague passed on genes to their modern descendants which allowed them to be resistant to hiv.
c. the bodies of individuals with a resistance to hiv contain small numbers of the bacteria linked to the plague which enabled them to be resistant to hiv.
d. individuals who survived the plague have stronger immune systems, and as a result, their descendants have immune systems strong enough to be resistant to hiv.

With the description of the different cell walls, membranes, and associated proteins set in the students' minds, you now need to introduce them to the idea that the cell wall can also act as a foundation to build things upon. bacterial appendages require a strong foundation that will offer the support needed to move and function in a dynamic world. for example, flagella are long, whiplike protein structures that are used by many gram-positive and gram-negative bacteria for locomotion. in order to function effectively, a flagellum must be firmly anchored to the cell wall. how will you be able to get across the idea that the peptidoglycan cell wall is strong enough to support such a mechanism? with a protein rod that passes through the cell wall and protein rings used to anchor it in the membranes, these basal bodies are the rudimentary biological motors that use atp power to spin the hook and the flagella attached to it. bacterial flagella have a biological motor that spins within the cell wall and is powered by atp. this allows the flagella to spin in a whiplike motion to propel the bacterium.

Mutations associated with albinism affect proteins involved in synthesis

Which describes a grizzly bear’s habitat?