7 Comments

1. 

   mensahc on October 13, 2015 at 9:20 pm

   1
   a) The calcium attaches with troponin, causing this molecule to move on the actin myofilament. As a result the the troponin on the actin filament shifts its position, exposing myosin binding site on the actin filament. This allows the myosin head to bind with the actin filament, creating cross-bridges.

   ii)) The muscle cell contracts when the myosin heads, readjusts is shape, and forms a cross bridge with the actin filament.

   b) Adenosine Diphosphate is converted into Adenosine Triphosphate by the adding of an inorganic phosphate molecule. This allows the myosin myofilament to create the initial phase of a muscle contraction. The ATP is then converted into ADP and the energy released from this exothermic reaction is used to break this cross bridge and allow the cycle to start all over again.

   2
   a) Phosphocreatine allows, ADP to be converted back into ATP, through a chemcical reaction which also produces creatine.

   b-(i) Large amounts of glycogen present in the muscle fibres means that large amounts of energy can be used ti fuel intense muscle contractions.

   (ii) Slow muscle fibres have capillaries in close contact, this allows a large blood supply to the slow twitch muscle fibres. This allows large contents of oxygen to be supplied to the muscle fibre, to fuel aerobic respiration.

   Reply
   • 

     kcritchley on October 19, 2015 at 10:38 am

     Nice work, Curtis!

     You and Reiss will be peer asessing these in class so watch this space for your feedback!

     Reply
     • 

       kcritchley on October 19, 2015 at 5:46 pm

       Right! I have to say REiss very accurately corrected your work today though I do abhor the term “peachy.”

       Please snure you descirbe the temporary binding and shape change of the head.

       I would add the following to extend this piece. Reply Below:

       How does a nearby capilliary bed aid respiration?

       Reply
2. 

   mensahc on October 19, 2015 at 11:35 am

   3

   Adenosine Diphosphate is converted into Adenosine Triphosphate by the adding of an inorganic phosphate molecule. This allows the myosin myofilament to create the initial phase of a muscle contraction. The ATP is then converted into ADP and the energy released from this exothermic reaction is used to break this cross bridge and allow the cycle to start all over again.

   The calcium attaches with troponin, causing this molecule to move on the actin myofilament. As a result the the tropomyosin on the actin filament shifts its position, exposing myosin binding site on the actin filament. This allows the myosin head to bind with the actin filament, creating cross-bridges.

   4
   a)
   (i)
   (ii)

   b)
   (i) 2.8 milliseconds
   (ii)
   (iii)
   (iv)

   c)
   Insecticides are effective at killing of insects as they prevent the muscle contracttions in the insect from occurring. This is because they inhibit the acetylcholine from being hydrolysed by this enzyme, preventing muscle functions and important transport of nutrients.

   d)
   e)
   (I) The calcium attaches with troponin, causing this molecule to move on the actin myofilament. As a result the the tropomyosin on the actin filament shifts its position, exposing myosin binding site on the actin filament. This allows the myosin head to bind with the actin filament, creating cross-bridges.

   (ii) Mitochondria is the site where ATP is produced through the Krebs cycle, this provides energy for the attachment and detachment of the mysoin head onto the actin filament, which causes the muscle cointraction.

   5
   a)
   1. Many Mitochondira
   2. Deeply Situated

   Reply
3. 

   Reiss Amoah on October 19, 2015 at 11:37 am

   1)
   a)

   i)good but you wrote troponin “shifts its position, exposing myosin binding site on the actin filament.” this is only correct for TROPOMYOSIN.

   ii) Add that the changing of the shape of the Myosin head pulls the Actin filament along the Myosin, which causes Sarcomere to contract.

   b) Mention that ATP is hydrolyzed to form ADP to produce the energy required to alter the shape of the Myosin head (this causes it to reach binding sites on Actin filament).

   2)
   a) No issue.

   b)
   i) You said “ti” instead of “to”.
   ii) Peachy.

   Reply
   • 

     kcritchley on October 19, 2015 at 5:43 pm

     Thanks, Reiss. I have recorded your missing homework. Please post it to your own Hippo site and I will check it when I am notified. Link below just in case this time please.

     Reply
     • 

       kcritchley on October 19, 2015 at 5:47 pm

       A simply punctuation error- It’s Kreb’s Cyle not Krebs Cycle. Kreb was a man. Please correct.

       Looking forward to next week’s work chaps!

       Reply