When it comes into contact with a host cell, a virus can insert its genetic material into its host, literally taking over the host's functions. An infected cell produces more viral protein and genetic material instead of its usual products. Some viruses may remain dormant inside host cells for long periods, causing no obvious change in their host cells (a stage known as the lysogenic phase). But when a dormant virus is stimulated, it enters the lytic phase: new viruses are formed, self-assemble, and burst out of the host cell, killing the cell and going on to infect other cells. The diagram below at right shows a virus that attacks bacteria, known as the lambda bacteriophage, which measures roughly 200 nanometers
Answer:
A. There are fossils of extinct ancestors of horseshoe crabs and the species is still alive today.
Explanation:
C and D have more to do with how it can be a fossil. It is a living fossil because its ancestors have been found in fossils, yet it continues to live today.
D,record observations and measurements.
This is not a question. Do you need anything answered?
Answer:
C) It involves interactions between biotic and
abiotic factors.
Explanation:
Ecosystems need energy imput, need both consumers and producers, and can exist on land, lakes, rivers and oceans.
