Click on a lesson name to select.
Chapter 7 Cellular Structure and Function
Section 1: Cell Discovery and Theory
Section 2: The Plasma Membrane
Section 3: Structures and Organelles
Section 4: Cellular Transport
Thin, flexible boundary between the cell
and its environment
7.2 The Plasma/Cell Membrane
Cellular Structure and Function
Allows nutrients into the cell and wastes to
leave.
Chapter 7
Composed of the phospholipid bilayer.
Cellular Structure and Function
Consists of a glycerol backbone, two fatty acid
chains, and a phosphate group.
Chapter 7
Selective Permeability or semi-permeable
Cellular Structure and Function
Lets some things in but not others. Sugars are
too big. Ex.-fish net, coffee filter
See picture p. 187
Chapter 7
Fluid Mosaic Model
Cellular Structure and Function
The phospholipid
bilayer allows other
molecules (proteins,
carbs, and
cholesterol) to “float”
in the membrane.
Chapter 7
Proteins
Cellular Structure and Function
Transmit signals inside the cell
Act as a support structure
Provide pathways for substances to enter and leave-
like sugars.
Chapter 7
Carbohydrates
Cellular Structure and Function
Identify chemical signals
Chapter 7
Cell Structure and Function
SPI 3210.1.2 Distinguish between
prokaryotic and eukaryotic cells.
EQ-What is the main differences
between these types of cells?
Parts of Prokaryotic Cells
1. Cell Wall in 99% of them
2. Cell Membrane
3. Cytoplasm
4. Ribosomes
5. DNA
6. Capsule (sometimes)
7. Flagella or cilia Capsule
• SPI 32101.1 Identify the cellular organelles
associated with major cell processes.
• EQ-What are the functions of the cell parts?
Cellular Structure and Function
Animal Cell Plant Cell
Plant and Animal Cell Structures
7.3 Structures and Organelles
Chapter 7
Cellular Pursuit
Cellular Structure and Function Chapter 7
Cellular Structure and Function
Animal Cell
Chapter 7
Cellular Structure and Function
Plant Cell
Chapter 7
Cellular Structure and Function Chapter 7
Membrane Transport
SPI 3210.1.7 Predict the movement of water and other molecules across selectively permeable membranes.
Essential Question: What type of transport is used by a potato placed in different solutions?
Passive Transport
Movement of particles across the cell
membrane without using energy-always
flows from high to low concentration
7.4 Cellular Transport
Cellular Structure and Function
Three Modes of Passive Transport 1. Diffusion
2. Facilitated Diffusion
3. Osmosis
Chapter 7
1. Diffusion
High to low movement of many particles.
Ex.=smell of baking cookies
Cellular Structure and Function
Initial Conditions Diffusion
Low High
High Low
Chapter 7
Diffusion is controlled by
Cellular Structure and Function
Temperature
Pressure
Concentration
Equilibrium=
Diffusion in = diffusion out
Molecules continue to move, but the overall
concentration remains the same.
Chapter 7
Diffusion in a Cell--selective permeability -
water and oxygen move this way.
Cellular Structure and Function Chapter 7
Concentration gradient
• A difference between concentrations
in a space.
• Molecules always move down
the concentration gradient, toward
areas of lesser concentration.
• Ex. –food coloring in water or air
freshener in a room.
2. Facilitated Diffusion
Cellular Structure and Function
Movement of materials across
proteins channels. Allows ions,
sugars and salts to pass.
Different solutes pass through
based on size, shape, and
polarity.
Chapter 7
Cellular Structure and Function
Carrier Proteins-
change shape to
help move
particles across
Channel Proteins-
allows substances
to cross through a
channel
Chapter 7
3. Osmosis
Cellular Structure and Function
Diffusion of water across a selectively
permeable membrane
Three Types of Solutions
Isotonic
Hypotonic
Hypertonic
Chapter 7
Water molecules
move to the area with
higher concentration
of solute (sugar in
the picture) and
therefore a lower
concentration of
water.
A simple rule:
• Salt is a solute, when it is concentrated
inside or outside the cell, it will draw the
water in its direction. This is why you get
thirsty after eating something salty.
Blood Cell Plant Cell
Isotonic Solution: Iso=same
Cellular Structure and Function
Water diffuses into and out of the cell at the
same rate.
11,397x
Chapter 7
Blood Cell
Hypotonic Solution: hypo=less
Cellular Structure and Function
Solute concentration is higher inside the cell.
Water diffuses into the cell so it swells.
Plant Cell
13,000x
Chapter 7
Plant Cell
Hypertonic Solution: hyper=more
Cellular Structure and Function
Solute concentration is higher outside the cell.
Water diffuses out of the cell so the cell
shrinks. Blood Cell
13,000x
Chapter 7
• 3210.1.8 Compare and contrast active and
passive transport.
• EQ-What are the main differences between
passive and active transport?
Active Transport
Cellular Structure and Function
When substances move against the
concentration gradient- low to high
Uses Carrier Proteins or pumps and
energy-ATP
Chapter 7
3 Types of Active Transport
Cellular Structure and Function
1. Na+/K+ ATPase pump
Moves Na+ ions out of the cell and K+ ions
into the cell
Chapter 7
Cellular Structure and Function
2. Endocytosis=Enter
Process by which the
cell surrounds and takes
particles into the cell
Requires energy
2 types:
1. phagocytosis-”cell
eating” for large
particles
2. pinocytosis-engulfs
liquid or small particles
Chapter 7
3. Exocytosis=Exit
• Secretion of material out of the plasma
membrane-uses vesicles
• Requires energy