Answer:
Placer mining can be less damaging to the environment than surface mines, as the sediment is returned to the water after the minerals have been extracted.
Explanation:
Opioid drugs. They disrupt the natural production of norepinephrine and act as central nervous system depressants. Opioids block pain sensations, induce drowsiness, reduce body temperature, and slow heart rate, blood pressure, and respiration functions.
Explanation:
The pulmonary valve (sometimes referred to as the pulmonic valve) is a valve of the heart that lies between the right ventricle and the pulmonary artery and has three cusps. It is one of the four valves of the heart and one of the two semilunar valves, the other being the aortic valve. Similar to the aortic valve, the pulmonary valve opens in ventricular systole, when the pressure in the right ventricle rises above the pressure in the pulmonary artery. At the end of ventricular systole, when the pressure in the right ventricle falls rapidly, the pressure in the pulmonary artery will close the pulmonary valve.
Answer:
Explanation:
c. stimulating the release of luteinizing hormone