What is found in all adult exhinoderms

Cladistics is a way of classifying organisms by examining the characteristics of their ancestors and descendants and depicting the relationships in a cladogram. which of the following best describes a challenge in classifying organisms this way? a. there are millions of species on earth, and a cladogram is not a practical means for classifying all of them. b. it is impossible to tell which organisms are most closely related to each other using a cladogram. c. cladograms are detail-oriented and do not provide a useful understanding of evolutionary relationships. d. there is a limited number of ways to organize the information, so most cladograms end up looking very similar.

The double bond between a carbon atom and two oxygen atoms (a molecule of carbon dioxide) has two characteristics. what are they? a. an ionic bond is formed between the oxygen and carbon atoms. b. four valence electrons are shared. c. two valence electrons are shared. d. valence electrons are shared between oxygen atoms.

Which of these statements is true about autotrophs, but not heterotrophs? a. they use sugar and oxygen to make carbon dioxide and water. b. they use chlorophyll and oxygen to make carbon dioxide and water. c. they use sunlight, water, and carbon dioxide to make sugars. d. they use sunlight, water, and oxygen to make chlorophyll.