The correct answer is; D
Homologous structures is the term used to describe physical similarities between related species that indicates a common ancestry.
Homologous structures are structures that have the same form or functions in different animals, indicating that the animals have evolved from a common ancestor. Homologous structures usually appear very similar in form but it may or may not have the same function in the different animals that are suggested to be related. The bones in the front limbs of many different mammals (such as humans, deer and bats) which are similar in their structure and arrangement are homologous structures.
Rivers, because rivers have currents that streamlined bodies are built for
They are a great way to beat the summer heat, with much milder temperatures at higher elevations bc there is fresh air, and studies have shown that living in higher elevations can have positive health benefits, such as improved cardiovascular health, weight loss, and longevity of life.
Answer:
Infectious dose refers to the minimum number or amount of pathogens required in order to produce a disease or its symptoms. In the given case, the bacterium is non-resistant and is treated with antibiotics.
The antibiotics help in neutralizing the infectious agents; however, full course should be done to eliminate the infectious agent completely out of the body.
If the course is left in between then, there are very high chances that some bacteria may survive. They might not produce disease or symptoms as they would be less than infectious dose.
However, with time, the survived bacteria gain more and more mutations during replication which can develop antibiotic resistance capability in them.
In addition, it is also possible that the survived bacteria can get R-plasmid (which has antibiotic resistant gene) from body's normal flora or from any other infectious agent present in the body by the process of transformation or conjugation.
The R-plasmid enables them to survive even in the presence of antibiotics due to which the treatment of the disease might become difficult.