Transcript Plasma Membrane Notes (7.2)

7.2 – The Plasma Membrane
State Standard
SB1a
Explain the role of cell organelles for both
prokaryotic & eukaryotic cells, including the cell
membrane, in maintaining homeostasis & cell
reproduction.
Chapter 7
Cellular Structure and Function
7.2 The Plasma Membrane
Homeostasis
 Living cells maintain a ____________ between
materials ____________ & ____________ the
cell.
 Their ability to maintain this balance is called
____________.
 It is important for a cell to control internal &
external concentrations of ____________,
____________, & other nutrients, while
eliminating cellular ____________.
Chapter 7
Cellular Structure and Function
7.2 The Plasma Membrane
Plasma Membrane
 Thin, flexible ____________ between
the cell and its environment
 Allows ____________ ____________ the cell
 Allows ____________ to ____________ the cell
Chapter 7
Cellular Structure and Function
7.2 The Plasma Membrane
Selective Permeability
 Property of the membrane that allows certain
materials to ____________
____________ the cell
while keeping others
____________
 It also allows ____________ cells to
perform different activities within the
____________ organism.
 Example: Human nerve cells respond to a
certain chemical that is present in the
bloodstream. Other cells are exposed to
this chemical but are not affected by it.
Chapter 7
Cellular Structure and Function
7.2 The Plasma Membrane
Basic Structure of the Plasma Membrane
 The plasma membrane is composed of the
____________ ____________.
 A phospholipid molecule is composed of a
____________ backbone, two fatty acid
____________, and a ____________ group.
Chapter 7
Cellular Structure and Function
7.2 The Plasma Membrane
Basic Structure of the Plasma Membrane Cont’d
 The ____________,
phosphate head of a
phospholipid molecule is
____________.
 The ____________, fatty
acid tail of a phospholipid
molecule is
____________.
Chapter 7
Cellular Structure and Function
7.2 The Plasma Membrane
Fluid Mosaic Model
 The phospholipid
bilayer allows other
molecules to
“____________” in
the membrane.
Other Components
 Proteins
 Cholesterol
 Carbohydrates
 Class Discussion: What is the
meaning of the word mosaic?
Chapter 7
Cellular Structure and Function
7.2 The Plasma Membrane
Proteins
 ____________ signals inside the cell
 Act as a ____________ structure
 Provide ____________ for substances to enter and
leave
Chapter 7
Cellular Structure and Function
7.2 The Plasma Membrane
Cholesterol
 ____________ fatty acid tails from
____________ together
Review: What
macromolecule
group to
cholesterols
belong to?
Chapter 7
Cellular Structure and Function
7.2 The Plasma Membrane
Carbohydrates
 ____________ chemical ____________