Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
11 Cards in this Set
- Front
- Back
Name the three groups of organisms that have cell walls. What are each of the walls made of?
|
Plants - cellulose
Bacteria - peptidoglycan Fungi - chitin |
|
What types of substances can pass through the lipid bilayer by simple diffusion? Give examples.
|
small, nonpolar, hydrophobic molecules
Ex: oxygen, carbon dioxide, cholesterol |
|
What types of substances require facilitated diffusion to pass through the lipid bilayer? Give examples.
|
large, polar, hydrophilic molecules
Ex: sodium, potasium, calcium (all ions), glucose |
|
What is the difference between passive transport and active transport?
|
Passive transport moves by diffusion. Active transport moves against the concentration gradient and requires energy.
|
|
How do the water gradient and the solute gradient compare?
|
They are opposite of each other.
|
|
How does water move across the cell membrane?
|
Water is a polar, hydrophilic molecule so it cannot move through the inner hydrophobic membrane. It uses a channel protein called an aquaporin.
|
|
If a cell with a tonicity of 0.9% and 99.1% water is placed in a solution that has 10% tonicity, what will happen?
|
The solution is hypertonic. Particles will move into the cell as water moves out. The cell will shrink.
|
|
If a cell with a tonicity of 0.9% and 99.1% water is placed in a solution that has 0.05% tonicity, what will happen?
|
The solution is hypotonic. Particles will move out of the cell as water moves in. The cell will swell and burst.
|
|
If a cell with a tonicity of 0.9% and 99.1% water is placed in a solution that has 0.9% tonicity, what will happen?
|
The solution is isotonic. There will be no net movement of particles.
|
|
Are human cells hypertonic, hypotonic, or isotonic? What are there tonicities?
|
Human cells are isotonic to a 0.9% sodium chloride (salt) solution.
|
|
What two things is the cell membrane made up of?
|
lipids and proteins
|