Sand dollars are radially symmetrical and have an internal skeleton but no backbone. Which phylum do sand dollars belong in?

A) chordates

B) echinoderms

C) arthropods

D) mollusks

What is an eruption of ash, cinders, bombs, and gases from a volcano is called?

Many scientists are concerned that the Oglala Lakota aquifer in the United States is being depleted at an alarming rate. What would most likely be a major effect of this aquifer running dry

Best defense for a bird?

Which of the following statements is true? All prokaryotes are part of the Protista kingdom. Mushrooms and yeast belong to the Plantae kingdom. Organisms in the Eubacteria kingdom do not have membrane bound organelles.

Draw a conclusion about the relationship of chloride ions to the excessively thick mucus in a patient suffering from cystic fibrosis

In which phase of meiosis does the chromosome number change from diploid to haploid? Prophase I Anaphase I Prophase II

Irene occasionally experiences unpredictable episodes of intense dread accompanied by chest pains and a sensation of smothering. Since her symptoms have no apparent cause, they would probably be classified as indicative of:

A scientist has discovered the means to block the chemical that directly provides cells with energy for cellular processes. Which cell substance is most likely to be inhibited by this discovery?

For questions 4 and 5, refer to the passage below. Many cells make and use an enzyme, called catalase, to facilitate the decomposition of hydrogen peroxide (H2O2). The products of the decomposition are hydrogen (H2) and oxygen (O2). 4.

Which scientific area is major force in shaping modern classification methods