Which of the following events occurred during the first trimester?
a. heart beat begins
b. lungs fully develop
c. bones become solid
d. fetus moves and kicks and swallows

How does the carbon cycle involve an exchange of carbon

In a cladogram, what occurs at a node? a derived trait appears. evolution is stopped. an ancestor dies. the cladogram ends. aa as s as ss what are the chances that their offspring will have sickle cell anemia? 0% 25% 50% 100%

Which particle controls what element an atom is?