Explanation:
Psi packaging Element is a cis-acting RNA element identified in the genomes of the retroviruses Human immunodeficiency virus (HIV) and Simian immunodeficiency virus (SIV) It is involved in regulating encapsidation of the retroviral RNA, an essential step in replication.
The <u><em>correct answer</em></u> is:
He needs to select a more representative sample.
Explanation:
Choosing students from the basketball team for the sample he uses on a study of heart rates and exercise will be a biased sample. This is because students on the basketball team are potentially healthier than other students, which means that exercise will not have a large an effect on their heart rate as it would if they were not as healthy and not as physically fit.
In order to reduce the amount of bias, he should choose students from different groups throughout the school.
Answer:
Indirect contact transmission occurs when there is no direct human-to-human contact.
Explanation:
There are two types of contact transmission: direct and indirect. Direct contact transmission occurs when there is physical contact between an infected person and a susceptible person. Indirect contact transmission occurs when there is no direct human-to-human contact.
