CH 3 Flashcards
What is the cell theory?
cells can arise only from preexisting cells
Human Cells have 3 basic parts, which are…
1) Plasma Membrane- flexible outer boundary
2) Cytoplasm- intracellular fluid containing organelles
3) Nucleus- DNA containing control center
memorize anatomy of cell
memorize anatomy of cell
What is passive process?
no energy required, goes with the concentration gradient
1) Diffusion- simple, facilitated, osmosis
2) Filtration
What is Active process?
energy required, goes against concentration gradient
What is a concentration gradient?
different concentrations of a chemical on either side of the plasma membrane
What is an electrical gradient?
different amounts of ions on either side of the plasma membrane
What is diffusion?
movement of a solute from an area of high solute concentration, to an area of low solute concentration until you reach equilibrium.
What is tonicity?
ability of a solution to change the shape of cells
What is simple diffusion?
: diffusion that occurs without any assistance from proteins; substances simple pass through membrane pores
What is facilitated diffusion?
diffusion that occurs with assistance from protein membrane channels/carriers
What is osmosis?
movement of solvent from area of low solute concentration to an area of high solute concentration
what is isotonic?
same concentration as the inside of a cell;
(RBC would stay the same)
What is hypertonic?
higher concentration than the inside of a cell;
(RBC will crenate/shrivel-up)
What is hypotonic?
solution that has a lower concentration than the inside of a cell;
(RBC will swell and lyse/burst)
What is exocytosis?
-transports into, across, then out of cell
What is endocytosis?
extracellular substances are taken into the cell
What are the 3 things that are endocytosis…
• Phagocytosis
• Pinocytosis
• Receptor-mediated endocytosis:
What is phagocytosis?
cell takes in large particles; “cell eating”
what is pinocytosis?
cell takes in small particles like fluid droplets; “cell drinking”
what is Receptor-mediated endocytosis?
receptor on plasma membrane must be bound to (activated) before substance is taken into the cell (mediated endocytosis)
What is resting membrane potential?
Electrical potential energy produced by separation of oppositely charged particles across plasma membrane in all cells
Difference in electrical charge between two points is referred to as voltage
Cells that have a charge are said to be polarized
Voltage occurs only at membrane surface
Rest of cell and extracellular fluid are neutral
Membrane voltages range from –50 to –100 mV in different cells (negative sign (–) indicates inside of cell is more negative relative to outside of cell)
What organelles are membranous?
Mitochondria
Endoplasmic reticulum
Golgi apparatus
Peroxisomes
Lysosomes
What organelles are non-membranous?
Ribosomes
Cytoskeleton
Centrioles
What is the function of cytoskeleton?
scaffolding
What is the function of Centrioles?
makes microtubules (cell division)
What is the function of Rough ER?
protein production
What is the function of Smooth ER?
fat production, detoxification
What is the Golgi Complex?
packaging
What is the Lysosome?
garbage collectors
what is the function of mitochondria?
ATP production
what is the function of ribosomes?
protein production
what is the function of the nucleus?
Chromosomes
what of the function of the nucleoli?
r-RNA synthesis (ribosomes assembly)
What is the function of the peroxisomes?
detoxification of free radicals
