Answer: Ultrafine particles cause poor health. Ultrafine particles are absorbed by the lungs when people breathe
Explanation: Its A and C
Bohr's model treats electron energy levels as clearly defined orbital paths around the nucleus like planets orbit the Sun. The cloud model treats the energy levels as probability clouds, regions in which electrons are likely to be found.
The signs of REM sleep include flickering of the infant's<span> eyes that are closed and brain waves that are rapid.</span>
When mpf activity declines in a normal healthy cell it is due to degradation of cyclin.
<h3>What is the cell cycle?</h3>
The cell cycle refers to the process by which new cells are formed by mitosis from an existing cells.
Several cell components are important in the cell cycle.
Cyclin is an important part involved in the cell cycle.
A decrease in cyclin due to increased degradation results in a decline in mpf activity.
Learn more about cell cycle at: brainly.com/question/8283140
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