Answer:
Cleaning.
Explanation:
Ultrasound are the high sound waves that has the frequency above than 20kHz. The ultrsonic sound can be detected by animals like bats and has medical importance as well.
The cleaning of the medical instruments and machines are done by ultrasonic cleaners. These cleaners uses the ultrasonic waves to clean the dirt and needs a proper solvent medium for cleaning. The cavitation bubbles are produced that are used for cleaning.
Thus, the correct answer is cleaning.
Answer: 7cm
Explanation:
The surface area of a sphere is calculated by using the formula:
A = 4πr²
Since the surface area is 616cm², using the formula given, the radius will be calculated thus:
A = 4πr²
616 = 4 × 22/7 × r²
616 = 88/7 × r²
Multiply both side by 7/88
616 × 7/88 = 88/7 × 7/88 × r²
49 = r²
r = ✓49
r = 7
The radius is 7cm
Answer:
THC’s chemical structure is similar to the brain chemical anandamide. Similarity in structure allows the body to recognize THC and to alter normal brain communication.
Answer:
b. The rats press the lever least when cocaine is presented.
Explanation:
Reinforcement or reward refers to the physiological processes by which a given behavior, such as drug use, becomes habitual. This occurs when neurons release the neurotransmitter dopamine to the nucleus accumbens (NAc) after drug use.
In tobacco, nicotine is the main component triggering of the reinforcement. Once inside the brain, nicotine activates nicotinic receptors, which in turn contributes to the reinforcement mechanism. Following repeated exposure to nicotine, a neuroadaptation process is established for some (but not all) effects of nicotine. Increased brain nAChRs (acetylcoline receptors) are observed in response to desensitization of these nicotine-mediated receptors. This desensitization can play an important role in the development of tolerance and dependence.
The fact that nicotine is a weak reinforcer, means that maybe the rat already had an neuroadaptation with this drug, not feeling anything with this drug anymore, and thats why he would prefer other drug, like cocaine, pressing the lever of nicotine less often.