KEYSTONE PREP #5

Life functions are performed at many levels of biological organization. Which level of biological organization is the simplest level at which a structure can support life functions?

• cell

• tissue

• organelle

• organ system

Cells are largely made of organic compounds that contain carbon. Which property of the carbon atom makes it an essential component of organic compounds?

• Carbon is a nonmetal.

• Carbon oxidizes to carbon dioxide.

• Carbon is solid at room temperature.

• Carbon can form four covalent bonds.

Use the list to answer the question.

A plant cell uses the molecules in the list to synthesize a protein. What role do the ATP molecules play in the protein synthesis process?

• They provide energy.

• They increase activation energy.

• They convert energy into hereditary information.

• They absorb excess energy to prevent overheating.

All living organisms must maintain homeostasis in order to survive. Which statement best describes one way humans maintain homeostasis?

• Temperature is regulated by giving off carbon dioxide.

• Water content is regulated by giving off carbon dioxide.

• Temperature is regulated by sweating.

• Water content is regulated by sweating.

The genetic material of two different individuals of the same species is analyzed. One individual has brown eyes. The other has blue eyes. Which characteristic for eye color would be the same for both individuals?

• the allele

• the DNA sequence

• the amount of pigment

• the location of the gene

New technologies enable oils to be extracted from plants to make renewable biodiesel fuel. Scientists have altered the genome of a specific plant species to increase the amount of oil produced by each plant. Which statement explains why this technology most likely benefits farmers?

• It makes each plant more resistant to disease.

• It lowers the cost of each acre of plants cultivated.

• It increases the value of each acre of land cultivated.

• It eliminates the processing needed to extract plant oils.

A population of squirrels was separated during the formation of the Grand Canyon. Over time the squirrels, separated by the canyon walls and the Colorado River, became unique species. Which mechanism most likely caused the development of the new species?

• habitat preference

• increased gene flow

• geographic isolation

• behavioral isolation

Use the statements to answer the question.

A teacher lists four statements for students to interpret. Which table of information correctly distinguishes between the statements?

• 
• 
• 
• 

Use the diagram to answer the question.

Which energy transfer most likely occurs between organisms in the food web?

• from owl to fox

• from rabbit to fox

• from sparrow to grass

• from mouse to grasshopper

In Pennsylvania, a nonnative plant called stiltgrass out-competes native plants in many forest ecosystems. Which statement best describes how the spread of stiltgrass negatively affects native herbivores?

• Stiltgrass stops the life cycles of native herbivores.

• Stiltgrass reduces the size of the native plant populations.

• Stiltgrass increases the flow of energy through the ecosystem.

• Stiltgrass attracts other nonnative plants to the forest ecosystem.