Science: Lesson 3

If the concentration of water in the air surrounding a plant is less than the concentration of water inside the plants vacuoles, water will diffuse into the _______ until the concentrations of water are equal.

Air

_____________ proteins allow ions to pass through the cell membrane.

Channel

Usually diffusion continues through a membrane until the ________________ of a substance is the same on both sides of the membrane.

Concentration

A cell uses _______________ to take in a substance by surrounding it with the cell membrane.

Endocytosis

Active transport uses the cells ___________ to move substances through a cell membrane.

Energy

Passive transport is the movement of substances through a cell membrane without using the cells ____________.

Energy

A cells vesicles release their contents outside the cell during _____________

Exocytosis

As a cell ___________, it's volume increases faster than its surface area.

Grows

Diffusion is the movement of substances from an area of __________ concentration to an area of __________ concentration.

Higher and lower

Carrier proteins carry ___________________ through the cell membrane.

Large molecules

Active transport moves substances from areas of __________ concentration to areas of ___________ concentration.

Lower and higher

A cell membrane is ______________, which means that it allows only certain substances to enter or leave a cell.

Semipermeable

Facilitated diffusion allows molecules to pass through a cell membrane using _____________ proteins.

Transport

For a cell to survive, it's surface area must be large compared to its _____________

Volume

Osmosis is the diffusion of __________ molecules only through a membrane.

Water