Bacteria and humans are similar in that they both*

Which cell structure is mainly responsible for releasing energy from food molecules in some single-celled organisms?*

During gas exchange, the cell membrane of a single-celled organism has the same function as which organ system in humans?*

An ecosystem is self-sustaining as long as organ- isms have sufficient quantities of energy, oxygen, minerals, and water. When organisms die, some of these materials are recycled back to plants in the ecosystem primarily through the activity of*

Which sequence represents structures organized from least complex to most complex?*

Which group consists entirely of organic molecules?*

A scientist plans to cut a segment of DNA so that it can be inserted into the DNA of a bacterium, a single-celled organism. The scientist needs to use a special type of organic molecule to perform this cutting process. This molecule is*

A finite resource in the environment that keeps a population from steadily increasing is known as*

Human reproduction usually involves*

Even though human proteins are synthesized from only 20 different amino acids, there are thousands of different proteins found in human cells. This great variety of proteins is possible because the*

Aphids, small insects that feed on the sap of plants, undergo asexual reproduction during the summer months. They produce eggs that are formed without the separation of chromosomes. These eggs do not need to be fertilized, and all of the resulting offspring are female.

The best explanation for all of these offspring being female is that*

Potato farmers in Ireland during the mid 1800s all grew the same type of potato. The potato plants were all produced as clones of one another. When a fungus infected the crop, all of the potatoes were destroyed. This occurred because these potato plants*

A cell is represented in the diagram below.

The coded information that the cell uses to synthesize many different proteins is stored in structure*

Wildflowers grow and reproduce during the spring snowmelt in the desert region of Death Valley, California. Which environmental factor would most likely have the greatest influence on these activities?*

Which statement best describes how a major change in the size of one population affects an ecosystem?*