Cell Processes Flashcards
What is diffusion?
Dissolved substances passing through a partially permeable membrane to get in or out is a cell
What is meant by a passive process?
No energy is required
Name some factors that affect the rate of diffusion
Temperature, concentration gradient and surface area
During diffusion, where do particles move?
From an area of high concentration to an area of low concentration, down the concentration gradient until an equilibrium is reached.
Where does diffusion occur in the human body?
Respiration, alveoli in the lungs, and in the intestines
What is the difference between diffusion and osmosis?
Osmosis is specifically the movement of water particles
What is a partially permeable membrane?
Part of a cell that only allows certain particles to pass through
What is meant by hypertonic?
Where the conceration of solutes, e.g. Glucose, outside the cell is higher than the inside.
In both human and plants, what happens when the cell becomes hypertonic?
Humans: the cell shrivels
Plants: the cell go flaccid
What is meant isotonic?
Where the concentration of solutes outside the cell is equal to the concentration inside.
What is meant by hypotonic?
The concentration of solutes outside the cell is lower than the inside.
What is active transport?
Using proteins to pump substances against the concentration gradient
Cells that use active transport have…
Lots of mitochondria
Where does the energy used in active transport come from?
Respiration
Where is active transport used?
Uptake of glucose and amino acids in the small intestine,
Absorption of mineral ions by plant roots.
