The following structures are found on the underside of fern leaves (microphylls) and contain sporangia:
a- sori
b- rhizomes
c- megaphylls
d- archegonia

economic impact of malaria is estimated to cost africa $12 billion every year. this figure factors in costs of health care, absenteeism, days lost in education, decreased productivity due to brain damage from cerebral malaria, and loss of investment and tourism.

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link:

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.