Animals, they only have a cell membrane, not cell walls.
I don't know what the answer choices were, though, but I hope this helps.
<span>Stem
cells develop into different types of cells as an organism grows. They also act
as internal repair systems. They divide without limit so as to replenish other
types of cells as long as the concerned organism is still alive. Stem cells
that develop to form either B cells or NK cells are normally found in the bone
marrow.</span>
Which of the variables affects the mass of the rock (samples)?
OR
which of the variables causes the breakdown of the rocks (samples)?
A.) The sewers cannot handle the volume of waste from street runoff...