Cell Biology Part 2 (2025)

Cells must bring in materials, like food and oxygen, and remove _______. These processes occur at the cell membrane.

• wastes

• energy

• proteins

• nutrients

Tags

NGSS.HS-LS1-3

Identify the structure labeled as the 'phospholipid bilayer' in the diagram of the plasma membrane.

• The double layer of blue spheres and tails forming the main structure of the membrane is the phospholipid bilayer.

• The small green circles scattered throughout the membrane represent the phospholipid bilayer.

• The long yellow strands attached to the surface are the phospholipid bilayer.

• The purple globular structures embedded in the membrane are the phospholipid bilayer.

Increasing surface area can increase the cell’s efficiency moving substances.

• True

• False

Cells of the digestive system have projections called ______ that aid in absorbing nutrients.

• villi

• cilia

• flagella

• microtubules

Tags

NGSS.MS-LS1-2

NGSS.MS-LS1-7

Diffusion - molecules tend to spread out; moving from areas of ______ concentration to ______ concentration. Fill in the blanks.

• high, low

• low, high

• equal, unequal

• low, equal

What is the process called that requires no energy and involves molecules moving from high concentration to low concentration?

• Active Transport

• Passive Transport

• Facilitated Diffusion

• Endocytosis

Based on the diagram, which type of passive transport involves a protein channel to help molecules move across the membrane?

• Diffusion

• Facilitated Diffusion

• Active Transport

• Osmosis

PURE water is not put in an IV Bag because:

• It can cause red blood cells to burst due to osmosis.

• It provides more nutrients than needed.

• It is too expensive to produce.

• It is more likely to cause infections.

How does water move in a hypertonic solution?

• Water moves out of the cell.

• Water moves into the cell.

• Water does not move at all.

• Water moves in and out equally.

How does water move in a hypotonic solution?

• Water moves into the cell.

• Water moves out of the cell.

• Water does not move at all.

• Water moves equally in and out of the cell.