Chapter 7

Question 1

Fluid Mosaic Model

Answer 1

The Most Widely Accepted Membrane Model. Fluid refers to the ability of it’s components to move around and Mosaic means it has a Patchy Appearence.

Question 2

Phospholipids

Answer 2

Arranged in two layers called a BLAYER with the Hydrophillic Heads (Water Loving) pointing in opposide directions because water is in and outside of the cell. The Hydrophobic (Water Fearing) Tails are insulated from the water.

Question 3

Membrane Proteins

Answer 3

Embedded in the Phospholipid Bilayer and can move about the Bilayer.

Question 4

Integral Protein

Answer 4

Extends into the Hydrophobic Region

Question 5

Peripheral Protein

Answer 5

Not embedded but bound to the surface of the membrane. Serve as passages for molecules to move accross the membrane. Transfer Proteins. May be enzymes or send signals.

Question 6

Signal Transduction

Answer 6

Joins cells together.

Serves as ID tag.

Question 7

Recognition Proteins

Answer 7

Attach to the ECM.

Attach the membrance to the cytoskeleton.

Question 8

Cholesterol

Answer 8

Found among hydrophobic tails in animal cells.

Beleived to aid in stabilizing the membrane.

Question 9

Carbohydrates -

Oligosaccharides

(Short Polysaccharides)

Answer 9

Found attached to Lipids, Glycolipids, or Proteins

Cell to Cell Recognition.

Important in Embryonic development and Immunity.

Question 10

Diffusion

Answer 10

The net movement of molecules by there own kinetic energy from an area of higher concentration to an area of lower concentration.

Question 11

Concentration Gradient

Answer 11

Exsists when there is a difference in the concentration of molecules in two areas.

Question 12

In diffusion moleculs move _________________.

Answer 12

down with the conentration gradient.

Question 13

Lipid Soluable (Steriods, hormones, oxygen, carbon dioxide) pass ___________________.

Answer 13

directly through the lipid bilayer.

Question 14

Water soluable molecules and ions ___________________.

Answer 14

pass through pores made of proteins.

Question 15

Osmosis

Answer 15

The diffusion of water across a differentially permeable membrane.

Question 16

Differentially Permeable Membrane

Answer 16

Some molecules can pass and some can not.

Question 17

Hypertonic

Answer 17

(Less Water)
A comparative term used to describe one of two solutions. Has higher concentration of dissolved material than the other solution.
(Less Water)

Question 18

Hypotonic

Answer 18

(More Water)

One of two solutions having a lower concentration of dissolved materials.

(More Water)

Question 19

Isotonic

Answer 19

(Equal Water)

Two solutions that are equal in dissolved materials.

(Equal Water)

Question 20

Facilitated Diffusion

Answer 20

The diffusion of molecules through the transport proteins. Follows Concentration Gradient.

Question 21

Diffusion, Osmosis, and Facilitated Diffusion are forms of ______________.

Answer 21

Passive Transport

Question 22

Passive Transport

Answer 22

Does NOT require energy input from the cell.

Question 23

Active Transport

Answer 23

The process of moving molecules through a protein molecule in the lipid bilayer from low to high area of concentration.

Question 24

In Active Transport the protein is activated ___________________.

Answer 24

by an energy boost from ATP, provided by the cell.

Question 25

Exocytosis

Answer 25

Movement of molecules out of the cell by means of a transport vesicle. Vesicle membrane fuses with plasma membrane so that vesicle contents are released. (EX=EXIT)

Question 26

Endocytosis

Answer 26

The movement of materials into the cell. The material becomes enclosed by a patch of plasma membrane and then sinks into the cytoplasm and forms a vesicle around it. (EN=ENTER)

Question 27

Phagocytosis

Answer 27

“Cellular Eating” Engulfment of foreign materials by means of Endocytosis. Forms food vesicles. Used by Amoebas and WBC.

Question 28

Pinocytosis

Answer 28

“Cellular Drinking” The Endocytosis of liquids. Occures on a smaller scale than phagocytosis and form vesicles containing the liquid.

Question 29

Receptor-Mediated Endocytosis

Answer 29

Proteins with specific receptor sites are embedded in the membrane of a cell. When the right molecule binds with the receptor it triggers the endocytosis of the molecule.