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28 terms

Physiology Ch3

third ch. of the tortora textbook.
STUDY
PLAY
what are the four characteristics of the cell membrane?
double layer of phospholipids
"gate keeper" (regulate what comes in and out)
amphipathic (both polar and non-polar qualities)
What model describes the plasma membrane?
Fluid Mosaic. it is a dynamic structure. NOT STATIC.
What are the substances that make up the Cell membrane?
lipids
proteins
What are the different types of lipids that make up the Cell membrane?
Phospholipids
Glycolipids
Cholesterol
Phospholipids
Amphpathic- polar and nonpolar
Make up 75% of the C.M.
Arranged in a bilayer
Glycolipids
20% of CM
Found on the outside of cell facing the ECF
Aid in cell adhesion, communication and regulation of cell growth
Cholesterol
5% of CM
Strengthens the membrane but reduces flexibility
What are the two types of membrane proteins?
Integral
peripheral
Intergral proteins
extend across the membranec among fatty acids. poke out on both sides. most are Glycoproteins.
Peripheral proteins
DO NOT extend though. attached to the inner or outer surface of the membrane.
*aid in the function of intergral proteins
What is the key concept of proteins?
membrane proteins and Glycoproteins largely reflect the the functions a cell can proform
What are the different types of Integral proteins
Marker
Receptor
Channel
Enzyme
Transporter(carrier)
Linker
(MR.CELT)!
Channel proteins (Ion Channel)
have pores where substances can easily pass in or out.
Transport protein
transports specific substances across CM by changing shape
Receptor protien
Recognized specific Lingand and alters cell function.
Enzymes
Catalyzes reactions inside or outside CM
Linker protein
provide structural stability by anchoring filaments inside or outside CM
Markers
Distinguishes one cell from another. Glycolipids and Glycoproteins
What are the functions of the Cell membrane?
Cellular communication
Est. electrochemical gradient
Selective permeability
Cellular communication
the cell must communicate w/ other cells, proteins, neurotransmitter, and hormones
Est. electrochemical gradient
the CM separates the ECF from the ICF and creates a chemical and electrical difference.
ECF
Greater Concentration of Na and Cl
ICF
Greater concentration K cations and PO4 anions. is more negative than the ECF
membrane potential
the difference in charges btwn the 2 sides of the CM create a Voltage Difference. for most cells -20mV and -200mV
what are the four major factors that determine membrane permeability?
lipid solubility
charge (Ion)
size
presence of channels or transports
Passive transport
no energy required
Simple Diffusion
Osmosis
Facilitated diffusion
Active transport
energy required
Primary ATP
Secondary ATP
Vesicular transport
Exocytosis
Endocytosis
Phagocytosis
Pinocytosis