It's a pyramid of numbers, I believe.
Answer:
yes their is
Explanation:
I don,t really know how to explain my answer
Answer:
A) the concentration of calcium ions in the sarcoplasm of a resting muscle
Explanation:
Sarcoplasmic reticulum is a system of the membranous sac that is present around each myofibril and is filled with calcium ions. When muscles are in the resting stage, calcium ions are stored in the sarcoplasmic reticulum.
As the muscle action potential triggers change in voltage-gated calcium ion channels of the sarcoplasmic reticulum, the channels are opened to release the calcium ions in the sarcoplasm. Increased calcium ion levels in sarcoplasm make the muscle fibers to contract.
Removal of acetylcholine from the synaptic cleft ends the production of muscle action potential and calcium ions are moved back from the sarcoplasmic reticulum.
Hence, lower levels of calcium ions are maintained in sarcoplasm when the muscles are in the resting stage.
Answer:
DNA or protein can be used as a ''molecular clock'' that tells how long it has been since two species have diverged from a common ancestor. The fossil record is usually derived from sedimentary rocks laid down millions of years ago.
1. Plastic is made of natural chemicals and is used for multiple things, such as culinary sets and water bottles
2. Metals are found in mines, and are used for currency and engineering
