Biology Chapter 8 Cells and Their Environment SodiumPotassium
Biology Chapter 8 Cells and Their Environment
Sodium-Potassium Pump • Carrier protein that uses ATP as it moves potassium ions and sodium ions across the cell membrane.
Cells • The human body contains two hundred and ten different cell types, that are found only in humans. Every cell in the body has a sodiumpotassium pump • Along with that there is the fact that there are over one hundred trillion cells in the body at any given time.
Cells • Each cell has a sodium potassium pump, this pump operates on an automatic mechanism of active movement that move the ions of potassium into the plasma membrane of a cell and the ions of sodium out of the plasma membrane of a cell.
Lipid Bilayer • Double layer that makes up a cell membrane
Concentration Gradient • The difference in the concentration of a substance across a region.
Facilitated Diffusion • A form of passive transport that involves membrane proteins that aid the movement of substances.
Active Transport • The moving of a substance to an area of higher concentration, using energy
Passive Transport • The moving of a substance to an area of lower concentration without any energy use.
Equilibrium • The state that exists for a substance when the substance is distributed evenly across a space.
Hypertonic Solution
Hypotonic Solution
Isotonic Solution
Cells in Solutions
Cells • The cell-surface markers identifies the cell type.
Cell Membranes • The outer surface is polar, while the interior is nonpolar.
Cells • By controlling what enters and leaves a cell, the cell membrane aids in maintaining homeostasis within the cell.
Cells • Small nonpolar molecules can pass unaided through the cell membrane
Diffusion • Is the movement of a substance down its concentration gradient
Facilitated Diffusion • When particles move out of a cell through facilitated diffusion, the cell does not experience any change related to energy.
Osmosis • The diffusion of water through a selectively permeable membrane
Endocytosis • Molecules that are too large to be moved through a cell membrane can be transported into the cell by endocytosis.
Osmosis • If the concentration of a sugar solution is lower outside the cell than inside the cell, water will move into the cell
Sodium-Potassium Pump • Is used to remove sodium from a cell and bring potassium into a cell against their concentration gradients
Vesicles • Endocytosis always involves the movement of a vesicle.
Cell Surfaces • When a molecule fits into the binding site of a receptor protein on a cell’s surface – The receptor can open an ion channel in the cell membrane – The receptor can act as a n enzyme, causing chemical changes in the cytoplasm – The receptor can cause the information of a second messenger
Receptor Protein • Membrane receptor proteins transmit information into the cell by responding to signal molecules
Messengers • A second messenger always carries a signal within a cell
Chapter 8 Test is tomorrow
- Slides: 29