Chapter 5 Membrane Structure and Function

Question 0

Fluid-Mosaic Model

Answer 0

• Fluidity of the membrane is critical
• Consistency of olive oil at body temperature
• Unsaturated fatty acids make it more fluid

Question 1

Fluid-Mosaic Model

Answer 1

-Membrane is a fluid phospholipid bilayer in which protein molecules are either partially or wholly embedded.

Question 2

Imbedded proteins may be __________ or _________.

Answer 2

Peripheral; Integral

Question 3

The ________ are held in position by interactions of the protein’s hydrophobic and hydrophilic region

Answer 3

proteins

Question 4

__________ proteins are found on the outer and inner membrane surface.

Answer 4

Peripheral

-Some inner peripheral proteins are held in place by cytoskeletal filaments.

Question 5

__________ proteins are embedded in the membrane.

Answer 5

Integral

Question 6

Both phospholipids and proteins may have attached ___________ ______

Answer 6

carbohydrate chains

-Glycolipids and Glycoproteins

Question 7

Glycolipids and Glycoproteins appear on the ______ surface of the membrane

Answer 7

outer

• used for
  
  1. protection
  2. cell adhesion
  3. Reception of signal molecules
  4. cell-cell recognition

Question 8

Membrane proteins have a variety of functions-

Answer 8

• Channel Proteins
• Carrier Proteins
• Cell Recognition Proteins
• Receptor Proteins
• Enzymatic Proteins

Question 9

Carrier Proteins

Answer 9

-combine with substance to aid in passage through membrane

Question 10

Channel Proteins

Answer 10

-provide an opening

Question 11

Cell Recognition Proteins

Answer 11

-Help body recognize foreign substances.

Question 12

Receptor Proteins

Answer 12

Allow molecule binding, causing protein to change shape and bring about cellular charge

Question 13

Passive Transport

Answer 13

• No ATP requirement

* Molecules follow concentration gradient

Question 14

Active Transport

Answer 14

• Requires carrier protein and ATP

* Can move substances up the concentration gradient

Question 15

A ___________ is a mixture of a solute dissolved in a solvent

Answer 15

solution

Question 16

_____________ is usually measure as Weight of solute / volume of solvent or Grams of solute/ liters of solvent

Answer 16

Concentration

Question 17

Molecules contain ______ energy

Answer 17

heat

-They vibrate and wander randomly

Question 18

____________ permeable is when only certain molecules can pass through

Answer 18

selectively

Question 19

________ cannot slip through the membrane or move through the hydrophobic interior

Answer 19

ions

Question 20

_________ _________ is the force that causes osmosis

Answer 20

osmotic pressure

Question 21

The _________ of a solution compares the concentration of one solution with the concentration of another solution

Answer 21

tonicity

Question 22

__________ ___________ - Solute and water concentrations both inside and outside the membrane are equal

Answer 22

Isotonic solution

Question 23

___________ _________- Cells places in a hypertonic solution will shrink

Answer 23

Hypertonic Solution

Question 24

___________ ____________-Cells placed in a hypotonic solution will swell

Answer 24

Hypotonic Solution

Question 25

___________ __________ -No ATP requirement

Answer 25

Passive Transport

Question 26

__________ _________ -Requires carrier and ATP

Answer 26

Active transport

-small molecules move against their concentration gradient

Question 27

Large Macromolecules are transported into or out of the cell by __________ __________

Answer 27

vesicle formation

*Proteins,polysaccharides, DNA

Question 28

Phagocytosis

Answer 28

Cell eating

Question 29

Pinocytosis

Answer 29

cell drinking

Question 30

_______ ___________- Specific form of pinocytosis using a coated pit

Answer 30

Receptor Mediated

Question 31

Animal Cells are surrounded by an __________ ________

Answer 31

Extracellular Matrix

Question 32

___________ _________-Intercellular filaments between cels

Answer 32

Adhesion Junctions

-hold cells together at cytoplasmic plaques

Question 33

Tight Junctions

Answer 33

• Impermeable barriers
• cells held tightly together directly by plasma membrane proteins
• Zipper like set of proteins

Question 34

Gap Junctions

Answer 34

-Plasma membrane channels are joined
*specifically for cell-cell communication
gives some strength

Question 35

Plant Cell Walls

Answer 35

• Plants have freely permeable cell wall, with cellulose as the main component
• Joined by plasmodesmata