Question

Q1. As ATP binds to the myosin head,

Select one:
a) the myosin head detaches from actin
b) the myosin molecule lengthens
c) the myosin head attaches more tightly to actin
d) the myosin molecule shortens
e) the myosin head's actin binding site is physically blocked

Q2. Which type of autonomic receptor is found on the adrenal medullary cells?

Select one:
a) alpha
b) nicotinic
c) beta-2
d) beta-1
e) muscarinic

Answer 1

1. Answer ; a) the myosin head detaches from the actin.

Reason ; In muscle contraction cycle, there would be a changes in the attachment of myosin with the actin, whenever it meets a new kind of ATP there would be a spontaneous release of actin from its head, which is mentioned in the above statement. Where as it will not lengthen or strongly attach with these protein molecules. Therefore the above mentioned option would be the right answer.

2. Answer ; B) nicotinic

Reason ; The type of autonomic receptor found on the above mentioned region of the endocrine gland is nicotinic type and it act in the preganglionic neuron part of the nerve transmission, there should not be muscarinic receptor at this place, therefore among the listed types of receptor the above mentioned type would be the most appropriate one founds at that region and other options are not relevant one.