Transport Across Cell-Membrane

• How is a cell membrane arranged?

  phospholipid bilayer
• What is facing inwards in the arrangement of the cell membrane?

  hydrophobic tails
• What is the function of the cell membrane?

  regulates the movement of substances in and out of the cell and provide protection and support for the cell
• What does the structure of the cell membrane contain?

  phospholipids & proteins & glycolipid & glycoproteins & cholesterol
• In the phospholipid group, which part is the polar group?

  hydrophilic head
• In the phospholipid group, which part is non-polar?

  hydrophobic tail
• What material is able enter/exit a phospholipid bilayer?

  lipid soluble material
• Why is the cell membrane described as a Fluid Mosaic Model?

  phospholipids can move and are flexible & proteins vary in shape, size and pattern
• What is the role of cholesterol in a cell membrane?

  steroid molecules connect phospholipid & reduces fluidity
• What is the role of glycoprotein in a cell membrane?

  cell recognition (antigen) & binding cells together
• What is the role of glycolipids in a cell membrane?

  cell recognition
• What is the definition of permability?

  ability for materials to pass through a substance
• What are factors that affect the cell membrane?

  temperature & solvent
• How does temperature affect the cell membrane?

  phospholipids will have more kinetic energy & move faster making a bilayer less gel-like and fluid
• How does solvent affect the cell membrane?

  denature proteins & push phospholipids out of orderly placement and increase movement & increases permability
• What are examples of solvents?

  water & acetone & ethanol
• What is the definition of Diffusion?

  net movement of particles/ions from an area of high concentration to an area of low concentration
• What type of process is diffusion?

  passive
• What are the factors that affect diffusion?

  temperature & concentration gradient & surface area & diffusion pathway
• What is the definition of carrier proteins?

  move larger molecules across membrane
• What is the definition of dilute?

  small quantity of solute dissolved in a solvent