Transport Across Cell Membranes

Mr. Anderson's video on Biology Essentials covers transport across cell membranes, focusing on passive and active transport. Passive transport includes diffusion and osmosis, which do not require energy. Facilitated diffusion involves proteins to move substances along their gradient. Active transport, requiring ATP, includes the sodium-potassium pump and large-scale movements like endocytosis and exocytosis. The video explains these processes with examples, highlighting their importance in biological systems.

What is the primary difference between passive and active transport across cell membranes?

• Neither requires energy.

• Both require energy but in different amounts.

• Passive transport requires energy, while active transport does not.

• Active transport requires energy, while passive transport does not.

Which process allows oxygen to enter the body and carbon dioxide to exit without energy?

• Osmosis

• Diffusion

• Facilitated diffusion

• Active transport

What happens to a cell in a hypertonic solution?

• It gains water and swells.

• It bursts due to excess water.

• It remains unchanged.

• It loses water and shrivels.

Which type of diffusion involves the movement of water across a semi-permeable membrane?

• Facilitated diffusion

• Osmosis

• Active transport

• Simple diffusion

What is required for facilitated diffusion to occur?

• A semi-permeable membrane

• A concentration gradient

• A protein to assist in transport

• Energy in the form of ATP

Which protein is involved in the facilitated diffusion of glucose?

• Sodium-potassium pump

• Glucose transporter (GLUT)

• Aquaporin

• ATP synthase

What is the main function of the sodium-potassium pump?

• To facilitate osmosis

• To maintain a gradient of sodium and potassium ions

• To transport water across membranes

• To move glucose into cells

Which process involves the engulfing of large particles by a cell?

• Exocytosis

• Endocytosis

• Facilitated diffusion

• Osmosis

What is the role of ATP in active transport?

• It stabilizes the cell membrane.

• It acts as a channel for molecules to pass through.

• It provides energy to move substances against their gradient.

• It helps in the diffusion of water.

Which process is responsible for releasing neurotransmitters across a synapse?

• Exocytosis

• Osmosis

• Facilitated diffusion

• Endocytosis