Chapter 7 Biology Flashcards
What is Homeostatsis?
the process of keeping the internal conditions in an organism stable.
this refers to the need for living organisms to maintain a stable internal environment to survive (temp., O2, nutrients, and pH)
What is Cellular Transport?
the movement of materials into and out of the cells
maintaining homeostasis
What is the Cell Membrane?
the membrane that surrounds the contents of a cell and allows only certain things in/out of the cell (protects) (contains protein)
What does selectively permeable mean?
the membrane only allows certain substances in (the substances that are allowed are considered permeable)
What is a phospholipid bilayer?
the 2 layers of phospholipid molecules arranged tail to tail that help make up cell membrane
What is the active transport?
process such as endocytosis and exocytosis that require some of the cells energy.
What is passive transport?
process such as osmosis and diffusion that do not require energy.
What is diffusion?
movement of RANDOM molecules from an area of higher concentration to lower. (lungs)
What is facilitated diffusion?
diffusion of molecules across a membrane through special proteins in the membrane
What is an equilibrium?
When concentrations on both sides are equal.
What is osmosis?
the movement of water across a membrane
always in water) (moves solutes
(greater on one side than the other) (selectively permeable)
What is solute?
dissolved particles
What is Hypertonic?
having a higher solute concentration outside the cell and causing the cell to shrink
What is Hypotonic?
having a higher solute concentration inside the cell and causing the cell to swell (hippo)
What is Isotonic?
having an equal solute concentration inside and outside the cell (no net movement)
Why did scientists call cells “mosaics”?
There are many parts working together just like a mosaic
Name three types of organisms that have cell walls.
plants, algae, fungi
What does a cell wall do?
provide support and protection made of cellulose
What is a solution?
a mixture of 2 or more substances