Biology 2 (Cell Division and Transport Across a Cell Membrane) Flashcards
Why would a cell divide
- Growth
- Repair
- Reproduction
- Renewal
Why not just get bigger cells
Big cells:
- not enough surface area gets covered
- it tkes longer to move things through them
- they are more susceptible to damage
What has to happen first
- Everything must be duplicated
- Everything must be duplicated
What does selectively permeable mean
Some things can pass through and some can’t
What does passive transport mean
Something moving naturally (without the use of external energy)
What does active transport mean
Something moving because of the external use of energy
What does concentration gradient mean
exists when there is a region of high concentration leading to a region of low concentration
What does diffusion mean
The spontaneous distribution of something from high concentration to low concentration
What does osmosis mean
The movement of water across a selectively permeable membrane
What does phosopholipid bilayer mean
consists of two layers of phospholipids, with a hydrophobic, or water-hating, interior and a hydrophilic, or water-loving, exterior
What does equilibrium mean
The amount of something exiting and entering is the same
What does hypotonic solution mean
Concentration of a solute is lower on the outside of a cell than on the inside
What does hypertonic solution mean
Concentration of a solute is higher on the outside of a cell than on the inside
What does endocytosis mean
the process by which cells take in substances from outside of the cell by engulfing them in a vesicle
What does exocytosis mean
the process by which cells excrete waste and other large molecules from the cytoplasm to the cell exterior
What does isotonic solution mean
Concentration of a solute is the same on the outside of a cell and on the inside
What does facilitated diffusion mean
Carrier proteins help pass some molecules through a cell membrane
What are some examples of molecules that can pass through the cell membrane in facilitated diffusion
- large polar molecules
- large ions
What is the difference between simple and facilitated diffusion
In facilitated diffusion, only 1 type of molecule can be carried
Is facilitated diffusion active or passive transport
active
What are the two stages of the cell cycle
- Growth stage
- Division stage
What is bulk transport
Bulk transport is used when molecules are too big to be transported normally
What are the two types of bulk transport
Endocytosis
Exocytosis
What is endocytosis
- Process by which cells INgest large materials
- Cell membrane engulfs material
- This portion pinches off, forming a membrane bound vesicle inside the cell called a vacuole
