电压门控离子通道:铰链细胞失水 entry of auditory ectorial membrane closed channel suppon hair cell open linking FeD:'. basilar membrane auditory nerve fibers BUNDLE NOT BUNDLE TILTED TILTED 应力激活的离子通道:2X1013N,004
电压门控离子通道：铰链细胞失水 应力激活的离子通道：2X1013N，0.04nm
3. Active transport: Carrier protein mediated movement up the gradient A. This process differs from facilitated diffusion in two crucial aspects s Active transport maintains the gradients for potassium sodium calcium. and other ions across the cell membrane Always moves solutes up a concentration or electrochemical gradient Active transport couples the movement of substances against gradients to ATP hydrolysis. i.e Always requires the input of energy
3. Active transport: Carrier proteinmediated movement up the gradient A. This process differs from facilitated diffusion in two crucial aspects: ❖Active transport maintains the gradients for potassium, sodium, calcium, and other ions across the cell membrane. Always moves solutes up a concentration or electrochemical gradient; ❖Active transport couples the movement of substances against gradients to ATP hydrolysis. i.e Always requires the input of energy
B. Cells carry out active transport in three main ways LIGHT electrochemical gradient ATP ADP+P COUPLED ATP-DRIVEN LIGHT-DRIVEN TRANSPORTER PUMP PUMP 8 Couple the uphill transport of one solute across membrane to the downhill transport of another. ouple uphill transport to the hydrolysis ofATP. .o Mainly in bacteria, couple uphill transport to an input of energy from light
B. Cells carry out active transport in three main ways ❖ Couple the uphill transport of one solute across membrane to the downhill transport of another. ❖ Couple uphill transport to the hydrolysis of ATP. ❖ Mainly in bacteria, couple uphill transport to an input of energy from light
C Direct active transport depends on four types of transport ATPases Exterior T T Y E ATP-binding ATP-binding region P-class pump F and V-class pump ABC superfamily The four classes ofATP-powered transport proteins P" type stands for phosphorylation ABC(ATP-binding Cassette)superfamily, bacteria--humans Two transmembrane(t) domains and two cytosolic ATP-binding(a)domains
C. Direct active transport depends on four types of transport ATPases The four classes of ATP-powered transport proteins: “P” type stands for phosphorylation; ABC (ATP-binding Cassette) superfamily, bacteria—humans. Two transmembrane (T) domains and two cytosolic ATP-binding (A) domains
今 The na+-K+ ATPase A coupling active transport to ATP hydrolysis. OuTINe >The Na*-Kt ATPase requires Kt outside. Nat and ATP inside, and is inhibited by ouabain CF CEL >The ratio of Na: K pumped 种1gur810TheN/ Pump. Tte Ne ' cum和 und in eit mmal cels toasts ef tan aand tao p sitn The a sbna are 3: 2 for each ATP hydrolvzed 1me如面am知Amr agosta Tne pump is soan in me E, tomatin, which is roen ID he ited of re oell tintin cf soum nre ta a >The Na*-K+ ATPase is a P-type comformational cango to the f form whicn coens to he outsde pump. This ATPase seruentially phosphorylates and dephosphory- K- and ouabain- lates itself during the pumping cycle. electrochemical astrochemical >The Nat-K ATPase is found Na° binding only in aniimals △DP+P
❖The Na+ -K+ ATPase ---A coupling active transport to ATP hydrolysis. ➢The Na+ -K+ATPase requires K+ outside, Na+ and ATP inside, and is inhibited by ouabain. ➢The ratio of Na+ :K+ pumped is 3:2 for each ATP hydrolyzed. ➢The Na+ -K+ATPase is a P-type pump.This ATPase seruentially phosphorylates and dephosphorylatesitself during the pumping cycle. ➢The Na+ -K+ATPase is found only in aniimals