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.
A derived character refers to a particular character that is shared by members of a particular population. Genes are considered to be derived characters because THEY ARE TRANSFER FROM GENERATION TO GENERATION FROM PARENTS TO THEIR OFFSPRING. Genes are derived from the DNA molecule of the parents and these are passed to their offspring during the process of cell division in reproduction.
Answer:
During Diffusion, molecules move from areas of high concentrations to areas of low concentration.
Diffusion does not require energy
When you swallow food, it doesn't just drop down into your stomach. Muscles contract in a wave-like motion to move the food along through the esophagus. This muscle movement is called, peristalsis, or peristaltic waves. These peristaltic waves contract behind the food bolus pushing it along the digestive tract.
