Define the Cambrian Explosion and include the dates

Why do you sandy beaches form at many sea shores

Which of the following are the functions of the skeletal system? blood cell production in soft marrow tissues and mineral reserves largest organ of the body for defense and support vitamin d production and pumping blood through vessels voluntary movement and contractile movement

Ineed the answer asap. in order to be considered alive, an organism must simultaneously possess the characteristics of homeostasis, heredity, cells, reproduction, and