Q: Answer the following question given this paragraph:      Q: What is the lowest level of organism that can perform all activities required for life?   Choices:  - system  - nucleus  - atom  - cell  A:
A: cell


Q: Answer the following question given this paragraph:   Even compounds with the same number of carbon and hydrogen atoms can have different shapes. These compounds are called isomers . Look at the examples in Figure below . The figure shows the structural formulas of butane and its isomer iso -butane. Both molecules have four carbon atoms and ten hydrogen atoms (C 4 H 10 ), but the atoms are arranged differently. Butane is a straight-chain molecule. Iso -butane is branched. You can see three-dimensional models of these two isomers at the URLs below. You can rotate the molecule models to get a better idea of their shapes.   Q: What are compounds with the same number of carbon and hydrogen atoms called?   Choices:  - alcohols  - hydrocarbons  - monomers  - isomers  A:
A: isomers


Q: Answer the following question given this paragraph:   Sponges are filter feeders. They pump water into their body through their pores. The water flows through a large central cavity called the spongocoel (see Figure above ). As the water flows by, specialized collar cells filter out food particles such as bacteria. Collar cells have tiny hairs that trap the particles. They also have a flagellum that whips the water and keeps it moving. Once the food is trapped, the collar cells digest it (see Figure below ). Cells called amebocytes also help digest the food. They distribute the nutrients to the rest of the body as well. Finally, the water flows back out of the body through an opening called the osculum. As water flows through the sponge, oxygen diffuses from the water to the sponge’s cells. The cells also expel wastes into the water for removal through the osculum.   Q: Filter feeders, such as sponges, pump water into their body through what structures?   Choices:  - fibers  - lungs  - valves  - pores  A:
A: pores


Q: Answer the following question given this paragraph:   In alcoholic fermentation , pyruvic acid changes to alcohol and carbon dioxide. This is shown in Figure below . NAD + also forms from NADH, allowing glycolysis to continue making ATP. This type of fermentation is carried out by yeasts and some bacteria. It is used to make bread, wine, and biofuels.   Q: In alcoholic fermentation , which acid changes to alcohol and carbon dioxide?   Choices:  - rain  - chloride  - lipoic  - pyruvic  A:

A: pyruvic