There are two types of transport in cells: passive transport, which does not require energy and involves diffusion of particles from areas of higher to lower concentration, and active transport, which uses cellular energy and is required for the diffusion of water across semi-permeable membranes or for maintaining concentration gradients of substances against their gradients. Osmosis is a type of passive transport where water diffuses through semi-permeable membranes from areas of higher to lower water concentration and can affect cell volume depending on the solution tonicity.

3. There are two types of transport mechanisms: passive
and active transport.
Passive transport does not require to
expend energy to occur, while active
transport needs to use energy in the cell.

4. This is the movement of particles
from an area of higher
concentration to an area of lower
concentration, thus leading to
equalization of the concentration
throughout the area of diffusion.

5. It is also defined as the spreading of
the particles of one substance among
the particles of another substance
following a concentration gradient (or
“downhill” movement of the
substance).

7. This is the diffusion of water across a semi-
permeable membrane. The two important
requirements for osmosis to take place are 1)
presence of a semi-permeable membrane and
2) presence of a concentration gradient. These
two affects the cell’s ability to gain or lose
water called as tonicity (isotonic, hypertonic,
and hypotonic).