12. To further describe the structure of atoms, fill in the blanks below.
Every atom consists of a central mass called the
__and a surrounding region (sometimes called the
electron cloud) that contains one or more
.The
move around the
at very high speeds. In the central mass we always find particles called
and
sometimes additional particles of equivalent mass called

Ry was studying two populations of the same species of lizards. one population lived on an island and the other lived on the mainland. both populations were affected by a hurricane that hit the island and the mainland with equal force. a year later, henry was testing the gene frequency and saw a decrease in genetic variation in the island species, but not in the mainland species. which best describes a conclusion he might have reached? gene flow greatly affects small populations, but large populations can recover. genetic drift greatly affects small populations, but large populations can recover. gene flow greatly affects large populations, but small populations can recover. genetic drift greatly affects large populations, but small populations can recover.