10 8 13 10 08 2013 Skeletal Muscle Motor implate when i release acetyl choline im gonna enough nicotinic receptors and get an action potential does down to t tubule then goes down through the t tubule The dhp protein goes for a riodine recepotor which later opens the calcium dhp receptor responds to the voltage change by changing its shape Actually a calcium receptor then calcium goes down into the cystocsol then bind to troponin pull tropmyosin out of the way then start a crossbridge cycle which is a repetitive cycle of this so four steps for cross bridge cycle o 1 Make the Cross bridge Calcium coming in move tropomysoin away make a bond with actin and myosin o 2 Cross bridge moves o 3 break the cross bridge break the bond o 4 change the shape of myosin head energize the myosin the cycle doesn t provide movement but it provides tension But can provide movement with how much tension produced Myosisn still has hydrolysis products Adp and p Calcium role Atp roles o break o memorize Latent period All or none rule we kinda follow Treppe get an increase in amount of tension with each muscle twitch contraction the environmental conditions are changing around it might have been temperature ion availability the way the muscles work when its cold or operating temperature as the muscles move they heat up a little so it works better when the muscle is being used Unfused tetanus get a little more contraction before its fully relaxed This is faster These are frequency tension relationships Fused tetanus is when you stimulate at the peak so it never relaxes Is a good thing because I can control it can turn it on and off these Trepp and tetanus break the all or none rule by changing the conditions frequency of the stimulous when I stretch a sarcomere the amount of actin and myosin overlap is the number of cross bridges affects the strength of the tension production length tension relationship we have an optimal length The more stretched a muscle is the lower the tension in a muscle contraction If I compress it the contraction strength decreases Because this is skeletal muscle its attached to bone so its already at its optimal length cant really change it But some muscles can stretch outside of this like muscles in teeth Muscle contraction requires energy have to have ATP to drive cross bridge cycle Creatine phosphate if I want a sustainable with fewest amount of bi products we go through oxidative phosphorlation Kreb cycle We need glucose Then we have CO2 which is relatively easy for us to get rid of 10 08 2013 10 08 2013