Answer: A
Explanation: Vaccines create memory cells with a weak version of the pathogen, so when they meet that pathogen again the body can respond more quickly and more efficiently since they have already been exposed to the pathogen.
Answer:
Renewable resources cannot disappear, non-renewables will not last forever. Non-renewable energy sources, such as coal, nuclear power, oil, and natural gas, are available in limited quantities.
Explanation:
A renewable resource, for example, is solar energy. It is renewable because the sun can never disappear.
Non-renewable resources take a long time to replenish, if this ever happens. Renewable resources naturally recharge over a relatively short period. Non-renewable resources are natural resources that exist in fixed quantities and can be utilized. Examples include fossil fuels such as oil, coal and natural gas.
Both types of resources have a big influence on biodiversity and people shouldn't be spending them without limit.
Answer:
Your answer is 2.
Explanation:
To calculate the mechanical advantage of a pulley you simply have to count the number of rope sections that support whatever object you are lifting (not counting the rope that is attached to the effort). For example, in a one pulley system the MA is 1. In a two pulley system the MA is 2.
Your answer is After DNA replication, the cell leaves S phase and enters G2, when the cell prepares for mitosis or meiosis. At the G2 checkpoint, the cell checks two things. First, it checks DNA for any damage that might have occurred during replication. It also ensures all the proteins needed for cell division are present.