Further Theory Flashcards
What is diffusion?
Diffusion is the distribution of particles that are in high concentration to equilibrium (i.e. equal distribution of particles inside an area).
Explain the process of active transport.
Active transport is the process in which dissolved substances that are needed by the cell are forced inside by carrier proteins. These substances occur in low concentrations outside the cell.
What is the diffusion of water called?
Osmosis
Explain the process of active transport.
Dissolved substances (that are in low concentrations) are locked onto the carrier proteins, then transported inside the cell where they are needed. This movement requires energy (ATP) and goes in the OPPOSITE direction to diffusion.
What is cell theory?
The cell theory states that all living things are made up of cells and cell products.
What are some examples of cell products?
Cell products include bones, teeth, hair, horn, and plant cell crystals.
What is bulk transport?
Bulk transport is the intake or output of solid particles (PHAGOCYTOSIS) and water droplets (PINOCYTOSIS).
[formation of a vacuole around solid particles/water droplets]
What is it called when a solid particle is taken in?
Phagocytosis
What is it called when a water droplet is taken in?
Pinocytosis
How do unicellular organisms gather nutrients?
Unicellular organisms depend on diffusion to supply nutrients, oxygen and removal of wastes. They may only grow to a small size as large size makes diffusion inefficient. This is because as surface area increases with volume, the SA:V ratio decreases, thus allowing less nutrients to diffuse into a cell in the same amount of time.
What is simple diffusion? Where does it take place, and what does it involve?
Simple diffusion occurs through the spaces in the lipid bilayer. This is the process in which small molecules such as water and oxygen diffuse into the cell, and small wastes such as carbon dioxide diffuse out the cell.
What is facilitated diffusion? Where does it take place, and what does it involve?
Facilitated diffusion is the process in which large molecules such as glucose are allowed to diffuse into the cell through the protein channel.
Dissolved particles may be called?
Solutes-
Water is often the solvent.
The cell membrane separates a cell from its external surroundings, and in doing so only allows certain substances to enter or exit. The cell membrane is ________ _________.
Selectively permeable
Why are cells so small in size?
When cells increase in size, their surface area also increases. This also means that the ratio between surface area and volume decreases, which makes diffusion less efficient.
