Cell Transport

What is the correct description of the relationship between osmosis and diffusion?

• Osmosis is a type of diffusion that pertains to just solute molecules and occurs across a cell membrane with the use of energy.

• Osmosis is a type of diffusion that requires extra energy on the part of the cell, whereas diffusion happens freely.

• Osmosis is a type of diffusion that pertains to just water molecules and occurs across a cell membrane without the use of energy.

• Osmosis is not directly related to diffusion. Osmosis involves the movement of liquids. Diffusion involves movement of gasses.

The main purpose of moving materials inside and outside the cell through the cell membrane is to create balance. What term do biologists use for “balance” in a cell?

• mitosis

• photosynthesis

• homeostasis

• cellular respiration

The sodium-potassium pump regulates the amount of sodium and potassium inside of cells, particularly nerve and muscle cells. In this process, an ATP molecule is used for energy, causing three sodium ions to be pumped out and exchanged for two potassium ions, which are pumped in by a membrane protein. Both ions go against their concentration gradients. The sodium-potassium pump is an example of:

• Active transport

• Diffusion

• Phagocytosis

• Passive transport

In the image on the right, the cell is taking in substances through membrane proteins, without any energy of its own. The substances naturally follow their concentration gradient. However, they must go through the protein channels, because they are too large to squeeze through the cell membrane. This process is called:

• Osmosis

• Endocytosis

• Active transport

• Facilitated diffusion

This component of the plasma membrane is used for cellular identification and communication inside living organisms.

• Carbohydrates

• Protein channel

• Phospholipid bilayer

• Cholesterol

This component of the plasma membrane provides a pathway for large molecules to cross.

• Protein channel

• Cholesterol

• Phospholipid bilayer

• Carbohydrate chain

This component of the plasma membrane helps with strength and flexibility, so the cell doesn't fall apart.

• Cholesterol

• Protein channel

• Phospholipid bilayer

• Carbohydrate chain

When water moves equally into and out of a cell it is in which type of solution?

• Hypertonic

• Hypotonic

• Isotonic

A cell is placed in a solution with 90% salt. The cell contains only 10% salt. The type of solution the cell has been placed in is:

• Hypertonic

• Hypotonic

• Isotonic

A cell is placed in a solution containing 20% glucose. The cell contains 25% glucose. What will happen to the size of the cell?