The water vascular system of echinoderms (A) functions as a circulatory system that distributes nutrients to body cells. (B) functions in locomotion and feeding. (C) is bilateral in organization, even though the adult animal is not bilaterally symmetrical. (D) moves water through the animal’s body during filter feeding. 4. Which of the following combinations of phylum and description is correct? (A) Echinodermata—radial symmetry as a larva, coelom (B) Nematoda—roundworms, internal skeleton (C) Platyhelminthes—flatworms, gastrovascular cavity, no body cavity (D) Porifera—gastrovascular cavity, coelom

Melting glaciers is a serious threat to the environment what is the possible consequence of melting glaciers on polar bears?

On a recent expedition to a remote region of northern canada, scientists uncovered skeletal remains from about 100,000 years ago. surprisingly, all the skeletal remains, which included many species from differing biological families and spanned about two thousand years, showed evidence of experiencing temperatures in excess of 1000 degrees fahrenheit (or 538 degrees celsius). which of the following, if true, best explains the apparent paradox between the cold environment and the evidence of the bones experiencing hot temperatures? (a) chemical changes that naturally occur during the process of decay in only one north canadian species produce the same evidence of the species' skeletons being exposed to hot temperatures as the expedition scientists found. (b) a little over 103,000 years ago, a large fire is known to have occurred in northern canada. (c) strong evidence exists that as early as 70,000 years ago, homo sapiens around the world relied heavily on fire to cook animals. (d) in the same expedition and in roughly the same layer of excavation, scientists found rudimentary wood cutting and hunting tools used by early humans.

Sarah and john are having a discussion on genetic diversity. sarah believes that it happen over a long period of time. john it happens immediately. who is correct? a. sarah is correct because genetic diversity occurs over a long period of time. b. john is correct because genetic diversity occurs immediately. c. both are correct because genetic variation can occur or long period of time. d. neither are correct because genetic diversity occurs over any period of time