HCHS Biology: Cell Transport

The cell membrane regulates what goes in and out of the cell by only allowing certain substances to pass through. Substances can cross the membrane by either passive or active transport. Passive transport includes

• diffusion.

• the sodium-potassium pump.

• exocytosis.

• endocytosis.

The cell membrane regulates what goes in and out of the cell by only allowing certain substances to pass through. Substances can cross the membrane by either passive or active transport. Active transport includes

• diffusion.

• the sodium-potassium pump.

• osmosis.

• transport NOT using cell energy..

A measurement of how much the concentration of a substance changes across a distance is called

• concentration differences.

• diffusion gradient.

• concentration gradient.

• transport gradient.

A substance moves through a membrane

from an area of high concentration to an area of

low concentration. Osmosis is the process of water molecules moving across a membrane. Facilitated is the process with the help of transport proteins. This paragraph is talking about (type the correct term here)

A substance moves against the concentration gradient (using energy from cells). When a cell's pump is in operation, sodium ions are pumped out of the cell, and potassium ions are pumped into the cell. Both ions move from areas of lower to higher concentration. In another example, The plasma membrane completely covers the substance, a vesicle pinches off from the membrane, and the vesicle carries the

substance into the cell.

These are examples of _________________ transport.

Cell membranes are selectively permeable (semipermeable), so some molecules can go in while others can’t. When water-repelling molecules like oxygen pass easily through the phospholipid (non-polar) bilayer, we classify the molecules as

• non-lipid-like.

• hydrophobic in respect to water.

• hydrophilic in respect to water.

• polar.

Cell membranes are selectively permeable (semipermeable), so some molecules can go in while others can’t. When polar molecules like ions cannot pass easily through the phospholipid (non-polar) bilayer, we classify the molecules as

• lipid-like.

• hydrophobic in respect to water.

• hydrophilic in respect to water.

• non-polar.

Which of the following is NOT one of the three ways for substances to move across a cell membrane?

• passive transport

• active transport

• vesicle transport

• active diffusion

Whci of the folloe=wing drawings best represents diffusion?

• 
• 
• 
• 

Which of the drawings represents label #4 in the drawing?

• ADP

• _Ki

• Sodium Na⁺

• ATP