Question

MEMBRANE STRUCTURE AND TRANSPORT ACROSS CELL MEMBRANES 1. An organelle that is characterized by extensive, folded membranes and is often associated with ribosomes 2. Label the following diagram Qutsde of cel LE nside of cell 3. List 4 functions of the plasma membrane c. d. 4. Complete the table below with the role cach component of the plasma membrane plays Plasma membrane components Role in the membrane Phospholipid Bilayer Cholesterol Glycopeoteins Glycolipids Protein Receptor Site Protein channel Protein Carrier 5. Why is the cell membrane also known as a "phospholipid bilayer?" 6. Glycolipids and glycoproteins have what type of molecule attached to them? 7. How many layers of phospholipids makeup the plasma membrane? 8. The cell membrane is both fluid and asymmetrical. Discuss asymmetry of the plasma membrane, as well as the enzyme involved. Explain properties that contribute to the fluidity of the cell membrane? 9. Give one way in which active transport differs from facilitated diffusion 10. Label the following diagram: Part A-Dfsion

Answer 1

DJ 1. Endoplasmic reticulum : When a ribosome begins to produce protein ER collect it and are pinched off in vesicles. Due to presence la Ribosomes it is called Rough Endo- plásmic reticulum. 2. As charbohydrate chain B- Integral protein co Hydrophobic tails De Cholesterol LE - Glycolipid fe - Peripheral protein IG- Phospholipid molecule H + Non-polar tail of Phospholipid molecules. 5. a) To facilitate cell to cell communication b) Transport of molecule-channel pumps c) To provide the cell with a selectively Ipermeable barrier / boundary. d) To provide some flexibility in structure I of cell! 5 I Phospholipid Bilayey • This layer makes up the cell membrane and is critical to a cell's ability to function. Cholesterol : 4 is major component of all cell membranes and is used to make essential molecule such as hormones fat- solu- be vitamines etc.

Glycoprotein: The hydrophilic nature allows them to function' in aqueous environment, where they act in cell-cell recognition and binding of other molecules. Glycolipid: They are the Lipid with a cambo- hydrates attached by a glycosidic bond. Their role is to maintain the stability of cell membrane etan Protein receptor sile : They bind to the signaling molecule and communicate in ward into the cell Protein channel: They facilitate the transport substances across a cell of membrane. Protein carrier: They facilitate diffusion of c molecules' across the cell memb. mane, Cell membrane is made up of two layers of bhospholipids arranged parallel to each other and each phospholipid molecules has a head and tail region