The rigid, outer layer of earth is referred to as the asthenosphere.
a. true
b. false

What does it mean for a cell membrane to be selectively permable

List two modern organisms that have pentameral symmetry

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.