What do the arrows on the graph below represent? a. extinction events
b. meteorite impacts
c. changes in earth temperature
d. the evolution of a new species

Which property is used to identify the origin of an igneous rock? color density hardness crystal size

Complete the possible outcomes for each generation in the pedigree chartaa aa aa

Why does meiosis produce cells with half the chromosomes? o a. most of the chromosomes are not necessary to keep an organism alive. b. a gamete needs only half the number of chromosomes because two gametes join together. o c. it makes the gametes easier to move around in the organism. o d. it is faster to produce gametes with fewer chromosomes.