POB ch 4

Question 1

why is the plasma membrane the fluid mosaic model?

Answer 1

Because there are a bunch of different parts to the plasma membrane (mosaic) and most of the proteins and phospholipids are able to drift slightly from side to side, which gives it a somewhat (fluid) structure.
Proteins=Mosaic
Lipids=Fluid

Question 2

what is selectively permeable ?

Answer 2

it means that some substances cross more easily than others.

• Small, Nonpolar, and soluble in lipids pass easily
• Large and charged molecules do not move easily through the phospholipid bilayer

Question 3

what is the phospholipid and what does it form?

Answer 3

lipid thats found in the cell membrane,

• glycerol molecule with a phosphate group at one end and 2 fatty acids at the other
• has a hydrophobic non polar head (fatty acids)
• has a hydrophilic polar tail (phosphate group)

Question 4

Proteins in the Plasma Membrane?

Answer 4

• channel proteins
• carrier proteins
• cell recognition proteins
• receptor proteins
• enzymatic proteins

Question 5

Chennel Proteins

Answer 5

allows molecules to move through a membrane through space provided by the protein
-move across freely

Question 6

Carrier Proteins

Answer 6

interacts and binds to a molecule to help it move across the membrane, usually requiring a change in protein shape

Question 7

Cell Recognition Proteins

Answer 7

glycoproteins that recognize pathogens/ determine if a cell belongs in your body or is an invader

Question 8

Receptor Proteins

Answer 8

Shape that allows specific molecules to bind to it ,

-binds to a specific extracellular molecule to bring about a change within the cell

Question 9

Enzymatic Protein

Answer 9

carry out metabolic reactions

Question 10

Isotonic

Answer 10

water concentration both inside and outside of the cell are equal!!!

Question 11

Hypertonic

Answer 11

water rushes out of the cell, causing the cell to shrink

Question 12

Hypotonic

Answer 12

water rushes into the cell, causing the cell to expand

Question 13

_________ is extremely important to the maintenance of the plants erect position

Answer 13

Turgor Pressure

Question 14

the swelling of a plant cell in a hypotonic solution creates _______

Answer 14

Turgor Pressure

Question 15

Diffusion

Answer 15

movement of molecules from a higher to a lower concentration
-does NOT require energy

Question 16

Osmosis

Answer 16

diffusion of water across a selectively permeable membrane due to concentration differences
-lower to higher concentration
(diffusion of water)

Question 17

Osmotic Pressure

Answer 17

Pressure that develops in a system due to osmosis, the greater the osmotic pressure, the more likely it will diffuse in that direction

Question 18

Facilitated Transport

Answer 18

• toward lower concentration
• down concentration gradient
• requires a carrier
• does NOT require energy

Question 19

Active Transport

Answer 19

• toward higher concentration
• against gradient
• REQUIRES energy
• needs a carrier

Question 20

Exocytosis

Answer 20

• big molecules go outside the cell
• REQUIRES energy
• vesicles fuse with plasma membrane

Question 21

Endocytosis

Answer 21

• big molecules go inside the cell
• REQUIRES energy
• vesicle formation

Question 22

Phagocytosis

Answer 22

• type of endocytosis

- when the particles taken in in endocytosis is large, such as food particles or another cell

Question 23

Pinocytosis

Answer 23

-liquids and small particles

Question 24

receptor Mediated

Answer 24

• from of pinocytosis that uses a receptor (signal) so that a specific molecule will bind to it
• involves coated pit

Question 25

Diabetes

Answer 25

- high blood sugar over a long period of time - frequent urination, increased thirst, etc. - symptoms have to do with homeostasis; getting back to equilibrium (isotonic state) - insulin receptors on muscle and liver cells - GLUT4 (carrier protein) embedded in membrane - vesicle merges with the cell membrane - glucose enters by Facilitated Diffusion