They make up an ecosystem that resides in an environment. For example, a rainforest is an environment that contains ecosystem like the trees, plants, animals and insects, the temperature, humidity and kind of soil.
I believe that C would be the best answer to this question.
I really hope that this helps you out
Bacille Calmette-Guérin (BCG) is a vaccine for tuberculosis (TB) disease. This vaccine is not widely used in the United States, but it is often given to infants and small children in other countries where TB is common. BCG does not always protect people from getting TB.
I think it would be a c shaped backbone
One of the reasons the plasma membrane can have<span> selective permeability</span><span> it's because it's composed by a bi-layer of phospholipids.
The interaction between them and other molecules will influence how these molecules will cross the membrane. If the molecule it's </span>hydrophobic it can easily cross, if it's polar molecules and ions( hydrophilic), they cannot cross easily.
