Topic 3 FAQ’s

Why don’t humans have a cell wall? Because we’re made up of animal cells, which do not have a cell wall! Who does (answer to #1 on podcast) Plants Fungi Bacteria Protists

Diffusion #2: High concentration to low concentration Doesn’t need membrane-NATURAL PROCESS Doesn’t need energy either! (molecules always moving) #3-FALSE-molcuels still move even in equilibrium

#4-Hypotonic LOW solute concentration outside the cell (high water) Water will move INTO the cell #5-This is better for plants Why water shoots out when you bite celery/apples Go to smartboard-ask where water will move-in, show in, show plant vs animal

#6 Hypertonic HIGH concentration of solute outside cell (low water) Water moves OUT Bad for everybody Show on smarboard

#7 Isotonic EVEN concentration of solute/water Note-water moves back and forth AT THE SAME RATE #8-Animals do better, plants will wilt smartboard

#9/10 Facilitate-to help Facilitated diffusion-diffusion across a membrane that needs a little help, specifically: Proteins Still doesn’t require any Energy!!

#11-Active transport Going AGAINST concentration gradient (low to high) Will NOT happen on its own-needs energy and proteins to help! Think: Active-need energy Would rather be spread out (no energy) than close together (more energy) Doesn’t happen as often because needs energy

#12-ATP Adenosine Tri Phosphate Cell’s immediate energy source

#13 ATP and Proteins ATP’s energy is used to change the shape of the protein Without it, wouldn’t be able to move anything from low to high (need for nervous system) Explain na k pump as you go

#14 Potassium and proteins In the sodium-potassium pump, when potassium binds, protein again changes shape

#15 3 ions sodium, 2 ions potassium

Diffusion A-Requires energy B-doesn’t require energy A-Requires a membrane B-doesn’t require a membrane A-High to low B-Low to high A-Involves proteins B-Doesn’t involve proteins

Facilitated diffusion A-Requires energy B-doesn’t require energy A-Requires a membrane B-doesn’t require a membrane A-High to low B-Low to high A-Involves proteins B-Doesn’t involve proteins

Active Transport A-Requires energy B-doesn’t require energy A-Requires a membrane B-doesn’t require a membrane A-High to low B-Low to high A-Involves proteins B-Doesn’t involve proteins