3. What organelle is known as the “gatekeeper” and allows
nutrients to enter and exit the
cell?
A. Cell wall
B. Cell membrane
C. Nucleolus
D. Mitochondria

The impact of science and technology on international relations

The process of rocks breaking down and becoming other rocks

Nami conducts an investigation on plants. she places a grow light on a timer to give the plants different amounts of light to see if this would affect their growth. in this investigation, the amount of light is the .