Answer: By definition, if the atomic number =
7
, then there are 7 protons, 7 electrons, and 8 neutrons!
Explanation:
The atomic number is by definition the number of protons, positively charged particles, contained within the atomic nucleus. So if there are 7 protons, there MUST be 7 electrons, 7 negatively charged particles. Why? Because matter is electrically neutral, and positive and negative particles must be equal.
Electrons have negligible mass; the mass number depends on the number of protons contained within the nucleus, PLUS the number of neutrons. Given that we have 15 N
, there must be 8 neutrons contained within the nucleus. does this help?
Answer:
Active transport of calcium into the sarcoplasmic reticulum.
Explanation:
- The sarcoplasmic reticulum (SR) is a membrane-bound structure found within muscle cells that is similar to the endoplasmic reticulum in other cells. The main function of the SR is to store calcium ions (Ca2+)
- In response to an action potential traveling along the t tubule, voltage-sensitive proteins change shape, opening calcium channels in the adjacent terminal cisterns of the sarcoplasmic reticulum.
Answer:
The nucleus tells other parts of the cell what to do
Explanation: