2.7 Facilitated Diffusion

• What type of transport is facilitated diffusion considered?

  Passive transport
• Facilitated diffusion requires energy because it moves molecules against the concentration gradient.

  False
• Facilitated diffusion does not require energy because it follows the concentration gradient.gradient
• What does facilitated diffusion use to move molecules across the cell membrane?

  Transport proteins
• In facilitated diffusion, molecules move down the **concentration gradient** with protein assistance.gradient
• Arrange the key differences between facilitated and simple diffusion:

  1️⃣ Requires specialized transport proteins

  2️⃣ Occurs down the concentration gradient

  3️⃣ Is faster due to transport proteins

  4️⃣ Does not require energy input
• Carrier proteins bind to specific molecules and change shape to transport them across the membrane.


  True
• What are the two main types of transport proteins that facilitate diffusion across the cell membrane?

  Channel and carrier proteins
• Facilitated diffusion requires transport proteins to shuttle molecules across the membrane.proteins
• What is the rate of diffusion in facilitated diffusion compared to simple diffusion?

  Faster
• How does facilitated diffusion differ from simple diffusion in terms of protein requirement?

  Requires proteins
• Both facilitated diffusion and simple diffusion require energy to move molecules across the cell membrane.

  False
• Why is facilitated diffusion faster than simple diffusion?

  Transport proteins
• What are the two main types of transport proteins involved in facilitated diffusion?

  Channel and carrier proteins
• Channel proteins allow molecules to pass through a pore or channel.


  True
• Carrier proteins undergo conformational changes to shuttle molecules across the membrane.


  True
• Examples of channel proteins include ion channels and aquaporins
• What are ion channels specialized transport proteins essential for?

  Maintaining membrane potential
• Gating refers to the opening and closing of ion channels in response to stimuli.


  True
• Mechanically-gated channels respond to physical stress
• What is required for facilitated diffusion but not for simple diffusion?

  Transport proteins
• Why is facilitated diffusion faster than simple diffusion?

  Transport proteins
• Facilitated diffusion helps molecules move down their concentration gradient
• Facilitated diffusion requires energy to move molecules across the membrane.

  False
• Which type of transport protein is highly selective and allows only certain molecules to pass through?

  Channel proteins
• Both channel and carrier proteins facilitate diffusion by moving molecules against their concentration gradient.

  False
• Steps in ion channel-mediated transport

  1️⃣ Stimulus triggers channel opening

  2️⃣ Ions move through the channel

  3️⃣ Gating mechanism regulates ion flow
• What type of ion channel responds to changes in membrane potential?

  Voltage-gated channels
• Facilitated diffusion requires energy to move molecules across the membrane.

  False
• Simple diffusion moves molecules down their concentration gradient without protein assistance.


  True
• Neither facilitated diffusion nor simple diffusion requires energy input.


  True
• What conformational changes do carrier proteins undergo during facilitated diffusion?

  To shuttle molecules
• What is a key characteristic of ion channels in terms of specificity?

  Highly specific to certain ions
• What are the two main types of transport proteins that facilitate diffusion across the cell membrane?

  Channel proteins and carrier proteins
• What are ion channels essential for in biological systems?

  Maintaining membrane potential
• What does selectivity in ion channels ensure?

  Accurate transport of specific ions
• Ligand-gated channels open upon binding of specific ligands
• What are the three key steps in carrier protein-mediated transport?

  Binding, conformational change, release
• GLUT proteins facilitate the diffusion of glucose across the cell membrane down its concentration gradient.

  True
• Facilitated diffusion allows molecules to move down their concentration gradient without using energy