Which represents the correct order of cell organization after cellular differentiation (simple to complex)?
a) organ system→organ→tissue→cell
b) cell→organ→organ system→tissue
c) tissue→cell→organ→organ system
d) cell→tissue→organ→organ system

Explanation:

the correct answer is d. to list systems from simple 2 complex, u have to go from cell (the smallest) to most complex (organ system) multitude of cells working in unison to accomplish the goal of digestion, or homeostasis.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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