Answer:Valves stop blood flowing backwards
Explanation: Valve are flags of tissue that control the direction of the blood in our heart.,it prevent the backwards flow of blood. valves regulate blood from flowing back into the atria.The right and left atrio-ventricular valves prevent blood from flowing backwards into atria. When the ventricle is full,the valve prevent backwards flow of blood.
A virus infects the cell by attaching fibers of its protein tail to a specific receptor on the bacterial cell wall and then injecting the nucleic acid into the host, leaving the empty capsid outside.
In viruses with a membrane envelop, the viral envelop merges with the host cell membrane and is taken in to the host cell by a process called pinocytosis, then releases its nucleic acid inside the host cell to be intergraded with host cell genome.
Answer:
According to the ICSM (Intergovernmental Committee on Surveying and Mapping), there are five different types of maps: General Reference, Topographical, Thematic, Navigation Charts and Cadastral Maps and Plans.
Once they understood the structure of DNA a lot of things became more clear including how DNA was replicated.
So I think your answer is copies? meaning how it is copied (replicated).
The structure also led later on to how it was transcribed into mRNA (and eventually into proteins by ribosomes).
