Answer: B
Explanation:
The T helper cell needs to acttivate the T cyctotoxic cell in order for the Tc cell to go do its work.
Once the TC cell is active it interacts with MHC-1 proteins on the surface of the infected host cell, this allows the Tc cell to recignise the host cell and begin secreting cytotoxins (perforins and granzymes) in order to degrade the infected cell and cause apoptosis (controlled cell death)
<span>A CO2 molecule found a friendly stomata on the bottom of a leaf. As the sun rose, the leaf's cells opened up to let the molecule in through the stoma. Soon, it was moving around inside with other CO2 and water molecules.
Soon, the plant--powered by the sun--began re-assembling the molecule into new forms, adding and subtracting bits with other molecules, to make sweet glucose and release oxygen into the air.
A curious rabbit couldn't resist a few nibbles of the sweet leaves with their glucose, and soon the CO2 molecule, in its new form as glucose, was inside the bunny's belly, being converted into energy.</span>
Prenatal care as well as preconception can help prevent complications and inform women about important steps they can take to protect their infant and ensure a healthy pregnancy.