Healthy Cell 70% water 15% protein 10% fat 4% DNA and other
materials 1% carbohydrate
Slide 3
How do cells get what they need? Passively certain materials go
in and out of the cell through the cell membrane with out using any
energy Actively energy is required to bring nutrients into the cell
and energy is required to eliminate wastes from the cell
Slide 4
Two Methods cells use to get what they need Passive Transport
does not require energy Active Transport does require energy
Slide 5
Types of Passive Transport Simple diffusion Facilitated
diffusion Osmosis
Slide 6
Simple diffusion Simple Diffusion When substances (particles or
molecules) move from a an area of high concentration to an area of
low concentration across a selective semi permeable membrane
without any trouble or interference move from a an area of high
concentration to an area of low concentration
Slide 7
What is a selectively permeable membrane? It lets certain
materials in or out of the cell but not others. Its
particular!
Slide 8
Facilitated diffusion Molecules that have a certain chemical
make up look for a doorway or channel so they can get in or out of
the cell without using energy These doorway channels are selective
in what they let in and out of the cell
Slide 9
Osmosis The diffusion of water only The rate of diffusion of
water is dependent on temperature, pressure, and the concentration
of other substances like salt
Slide 10
Diffusion and Osmosis
Slide 11
Equilibrium is the goal of Passive Transport When the
concentration of the diffused particles is the same on both sides
of the semi permeable membrane The inside of the cell has the same
concentration of diffused materials as the outside of the cell
Slide 12
Homeostasis
Slide 13
Questions. Why is it important to keep the right balances of
water, oxygen, protein, carbohydrate and fats outside the cell? How
do we do this?
Slide 14
Active Transport
Slide 15
What does a cell do if. It is in equilibrium but it still needs
more diffusible materials? It needs nutrients that are too large to
passively go through the cell membrane? It needs to get rid of
wastes that are too large to passively leave the cell?
Slide 16
Active transport When substances move from an area of low
concentration to high concentration This does require energy! ATP
is the carrier molecule that provides the energy necessary for
active transport to occur Draw this!
Slide 17
Active transport: requires energy!
Slide 18
Endocytosis When the cell needs particles that are too large
and cannot pass through the semi permeable membrane
endocytosis
Slide 19
Exocytosis When the cell wants to get rid of particles that are
too large to pass through the semi permeable membrane -
exocytosis
