Select all that are true when a muscle fiber is at rest.

a. There is a charge difference across the sarcolemma.
b. There is a charge difference across the sarcolemma.
c. Sodium-potassium pumps are active.
d. Sodium-potassium pumps are active.
e. Calcium is stored in the sarcoplasm.
f. Calcium is stored in the sarcoplasm.
g. ACh receptors are open.

Options f and g

Explanation:

A muscle fiber at rest includes such characteristics that calcium ions have not been released and at still stored in the sarcoplasm (a form of ER). Its release will trigger muscle contraction. Another characteristics is that the acetylcholine receptors that binds the neurotransmitter acetylcholine are open i.e not yet bound to the neurotransmitter. Binding of the neurotransmitter to its receptor will trigger the release of calcium ion from the sarcoplasm thus initiating muscle contraction.

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.

after making a punnet square using bv bv bv bv you will find that the ratio will be 9: 7 or a 128.6% probability.

hope this