BIOLOGY 3 Flashcards
Diffusion.
The movement of small molecules from a high concentration to a low concentration down a concentration gradient through gaps in a membrane and its a passive process.
Active transport
The movement of substances, through a partially permeable membrane, against the concentration gradient and it requires energy from respiration.
Osmosis
The movement of water, through a partially permeable membrane, into a solution with a lower water concentration
Partially permeable membrane
a membrane which allows water and other small molecules to pass through, but not larger molecules such as starch.
Flaccid
Lacking in stiffness or strength. Soft and floppy.
Emulsification
Breaking down large droplets of fat into smaller ones.
Enzymes
proteins that act as biological catalysts (they speed up reactions without being used up)
Denatured
when the shape of an enzyme’s active site changes so that the enzyme no longer works
Artery
blood vessels that carry blood away from the heart and towards an organ.
What does an artery look like?
Thick walls and small lumen to help maintain pressure of blood.
Vein
Blood vessels that carry blood back to the heart from an organ.
What do veins look like?
Thin walls, large lumen and valves to stop backflow of blood.
Valve
Short flaps which ensure blood only flows in one direction.
Lumen
Space inside a blood vessel.
What reagent is used to test for starch?
Iodine solution.
