Transport across Cell membrane

Question 1

What is osmosis ?

Answer 1

Moment of water across a semi-permeable membrane from a region of high water potential to a region of low water potential

Question 2

What is Simple diffusion ?

Answer 2

Movement of small , non-polar or hydrophobic molecules from an area of high conc. to an area of low conc. across the phospholipid bilayer

Question 3

What is facilitated diffusion ?

Answer 3

• Channel proteins allow specific large , polar or hydrophilic molecules to pass through phospholipid bilayer
• Carrier proteins take in specific molecule from outside the cell then change shape allowing molecule into the cell

Question 4

What is Active transport ?

Answer 4

Movement of molecules from a area of low concentration to an area of high concentration up the gradient requiring energy

Question 5

What is Co-Transport ?

Answer 5

One molecule joins another in the same carrier protein without any additional energy usage