Biology Forums - Study Force

I know this is a long question, but if anyone could help me I will greatly appreciate it!

Part 1 which of the following are true for myosin

1. each myosin head has a binding site for actin and ATP
2. during muscle contracting, thick and thin filaments slide past each other causing an overall lengthening of the muscle.
3. in a muscle cell, myosin tails group togethe to form a thick filament.
4. the myosin-actin rxn cycle is powered by atp hydrolysis.
5. the interaction between myosin and actin converts chemical energy to mechanical work.
6. the head of the myosin molecule acts as a molecular lever.



Part 2

which are true for kinesin

1. kinesin has a low processivity
2. kinesin molecules have a stiff neck region between the globular head and the tail.
3. each kinesin head has a tubuli-binding site and a nucleotide-binding site.
4. kinesin's cargo binds to the light chains of the kinesin molecule.
5. kinesin requires the energy produced from ATP hydrolysis to move its cargo.
6. kinesin moves its cargo toward the negative end of the microtubule.

thank u so much for your help!

which are true for kinesin

1. kinesin has a low processivity
2. kinesin molecules have a stiff neck region between the globular head and the tail.
3. each kinesin head has a tubuli-binding site and a nucleotide-binding site.
4. kinesin's cargo binds to the light chains of the kinesin molecule.
5. kinesin requires the energy produced from ATP hydrolysis to move its cargo.
6. kinesin moves its cargo toward the negative end of the microtubule.

I have tried this question several times and I still get the incorrect answer.

For myosin I said that 1-5 were true, but it is wrong.

For kinesin, I said that 6 is wrong and all the others are right, and it does have a low processivity.  But my answer is marked wrong.

Any help will greatly be appreciate it!

Thanks again.

hey nickname,

Here is some information I found.

- Kinesins generally move towards the plus end of a microtubule. Dyneins move towards the opposite end.
- They are ATP hydrolyzing.
- Cargo binds to the light chains of the kinesin molecule.
- each kinesin head has a tubuli-binding site and a nucleotide-binding site (For ATP of course).
- Kinesin still has a very low processivity.

So it should be 2,3,4,5, and 1 that are true

1. each myosin head has a binding site for actin and ATP
2. during muscle contracting, thick and thin filaments slide past each other causing an overall lengthening of the muscle.
3. in a muscle cell, myosin tails group togethe to form a thick filament.
4. the myosin-actin rxn cycle is powered by atp hydrolysis.
5. the interaction between myosin and actin converts chemical energy to mechanical work.
6. the head of the myosin molecule acts as a molecular lever.

Seems like all of them are correct :-\. Is that allowed?