BIo 111 1.04

Cell theory is one of the foundations of biology. What are the tenants of the cell theory? Check all that apply.

Cells carry genetic material passed to daughter cells during cellular division. Cells arise from other cells through the process of cell division. All living organisms consist of cells

Viruses contain DNA or RNA, but lack genes necessary for metabolism and reproduction. Why are viruses not considered to be alive?

Viruses are unable to reproduce independently of a host

Viruses defy characterization as living organisms even though they possess nucleic acids and proteins. The reason why viruses are not considered to be alive is because they

cannot reproduce without a host cell

Unifying themes of biology. For each statement below, indicate whether it is true or false.

1. All living organisms are composed of one or more cells. true 2. Different cell types develop in a multicellular organism because each cell has its own unique set of genes. false 3. Underlying similarities in biochemistry and genetics support the idea that all life evolved from a single ancestor. true 4. Molecules in different organisms that perform the same function are likely to have a similar structure. true 5. Evolutionary conservation explains the diversity of life. false 6. Information stored in inorganic molecules is used to direct the synthesis of cellular components. false 7. Cells process information stored in their DNA as well as information they receive from the environment. true 8. Organisms are closed systems that require an input of energy in order to maintain their high level of complexity and organization. false 9. Homeostasis is possible because elaborate signaling networks coordinate the activities of different cells within an organism. true 10. The unity of living systems arises through evolutionary change. false