The muscles of arthropods are attached to the outside of their exoskeletons, which are made of chitin.
a. true
b. false

How energy flows through each level in this energy pyramid. is all the matter and energy from one level transferred to the next level?

Number and variety of living organism; includes genetic, species, and ecological types

When designing a science presentation, look for credible sources. science doesn’t show bias, but humans do. avoid sites and articles that provide facts without citing proper scientific evidence. you must be able to identify reliable sites so that the data in your presentation is credible. use sources that end in .gov, such as cdc.gov. these government sites are reliable sources. you can also use sites ending in .edu. they are usually trustworthy, but sometimes students, not scientists, write content for .edu websites. always identify the source’s author before proceeding. some .org and .com sites are credible, but it’s important to verify their authenticity. when reviewing a source, ask these questions: who is the author? is this person an hiv or aids expert? what is the document’s purpose? does the document state facts that scientists can prove with evidence? are there opinions in the document? how old is the document? do other credible sources support the statements in the document? search for credible websites and note the information they contain. write down two sources that you will use for your presentation, and cite them using modern language association (mla) citation methods.