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Anatomy Ch. 3 Cells
Ch. 3 Cells: The Living Unit
Question | Answer |
---|---|
What is the smallest living unit in our bodies? | Cells |
What carry on essential functions of cells? | organelles "little organs" |
What separates two of the body's major fluid compartments-intracellular and extracellular fluid? | Plasma membrane |
Types of membrane proteins | 1. Integral, 2. Glycocalx, 3. Peripheral |
Integral Proteins | firmly imbedded in or attached to lipid bilayer |
Glycocalx | fuzzy, sticky, carbohydrate-rich area at the cell surface |
Peripheral Proteins | attach to membrane surface and support plasma membrane from cytoplasmic side |
hydrophillic head | polar |
hydrophobic tails | non-polar |
Passive Transport | molecular movement occurs spontaneously without input of energy; movement of molecules down their concentration gradient through integral protein |
Active Transport | molecular movement occurs only with input of energy; integral proteins move molecules across plasma membrane against concentration gradient |
Simple Diffusion | pass directly through lipid bilayer |
Facilitated Diffusion | move across lipid bilayer with help of carrier molecule |
Diffusion | tendency of molecules or ions to move from an area where they are in higher concentration to lower concentration |
What is the diffusion of water molecules across a membrane? | Osmosis |
Hypertonic | solute concentrations higher in extracellular fluid |
Hypotonic | solute concentrations lower in extracellular fluid |
Isotonic | solute concentrations are balanced |
What transports via integral proteins? | Active Transport |
What is the mechanism by which particles enter cells? | Endocytosis |
What is the type of endocytosis in which cell engulfs large particles by projecting pseudopods (false feet) around it and enclosing it within a membrane sac? | Phagocytosis |
What cell "gulps" drops of extracellular fluid containing solutes into tiny vesicles? | Pinocytosis |