Answer:
C
Explanation:
To send signals to the blood vessels to constrict or dilate , to increase or decrease blood flow respectively.
Answer: Layer a is 500 million years old.
Explanation:
Trilobite is a member of the group of extinct arthropods found as fossils and they can be identified by the three-lobed as well as three segmented forms. These were the marine animals. These were appeared initially in the Cambrian Period. They used to live 542 million years ago so the fossils can be estimated to be aged of 500 above years old. These animals used to dominate in the sea area.
Answer:
Nuclear decay rates are constant
Explanation:
Spontaneous decay of unstable nuclei is a process of a statistical nature, it is not possible to predict with certainty when an individual radioactive nucleus will decay, nor can the decay process be influenced in any way.
Therefore, the half-life of radionuclides (specific for each radionuclide) is defined as the time period in which half of the initial number of radioactive nuclei decays.
The unit of measurement for the radioactivity of the material is the becquerel (Bq) and denotes the number of decays in one second (1Bq = 1 decay / 1 second).
The major purpose(s) of mitosis is for growth and to replace worn out cells.
