it's D but I might be wrong
Which of the following is the best explanation
for the presence of both chloroplasts and
mitochondria in plant cells? - If plants cannot
produce enough ATP in the process of
photosynthesis to meet their energy needs,
they can produce it in aerobic respiration.
Sugars are produced in chloroplasts.
Activation of muscle contraction could be a speedy event that's initiated by electrical activity within the surface membrane and transversal (T) tubules. This can be followed by unharness of metal<span> from the inner membrane system, the sarcoplasmic reticulum.
</span>Nervous stimulation causes a depolarization<span> of the muscle membrane (sarcolemma) </span>that<span> triggers </span>the discharge<span> of </span>calcium<span> ions from the sarcoplasmic reticulum.</span>
Answer:
Prokaryotic cells are much smaller than eukaryotic cells, have no nucleus, and lack organelles. All prokaryotic cells are encased by a cell wall. Many also have a capsule or slime layer made of polysaccharide. Prokaryotes often have appendages (protrusions) on their surface.