The diagram below represents a cell and some molecules in its environment

The diagram below represents a cell and some molecules in its environment

(diagram attached)

Which molecule would require the use of energy to be brought into the cell?

4 (circle)

Explanation:

Substances move passively (without energy) from a high concentration to a low concentration across a semi-permeable membrane. This process is called diffusion. Energy would be required to move a substance from a low concentration to a high concentration (i.e. against a concentration gradient). This is called active transport.

In the image, only molecule 4 would need to move from a lower concentration outside the cell to a higher concentration inside the cell. This process would require energy.

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.