Describe how an invasive species can be introduced into an ecosystem by humans. Name a specific situation and species and how it would affect that ecosystem.

What is histamine and what is its role in allergic reactions

In the diagram below, the northern hemisphere would be in what season at position a a.fall b. winter c.summer d.spring

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? question 8 options: the cold balloon expands and rises. the warm balloon shrinks and sinks. the balloons rise at the same rate. both balloons are the same size. the ballons both rise. the cold ballon is larger than the warm balloon. the warm balloon expands and rises. the cold balloon shrinks and sinks.