Two species of frogs mate with each other. the embryo dies after a few cell divisions. what kind of reproductive isolation does this example represent?

During endocytosis, cells expel what they don't need take in what they need shrink due to loss of water

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.

Which number represents a basic ph, 4 or 9? numerical answers expected! answer for blank 1: i'll give