B4B

B4B The diagram illustrates the activity of vesicles during a cellular process .

Which statement best explains the function of the vesicles?

• Delivering packaged materials to the Golgi apparatus for protein synthesis

• Exchanging genetic information between the Golgi apparatuses of separate cells

• Extracting portions of the Golgi apparatus to be regenerated for growth within the cell

• Transporting packaged molecules from the Golgi apparatus to be re leased out of the cell

B4B When mammals get an infection, their internal body temperature often rises 2 to 3 degrees Celsius. The body gets the energy it needs to react to an infection by -

• increasing the rate of cellular division

• decreasing the rate of glucose movement into the cell

• increasing the rate of cellular respiration in mitochondria

• decreasing the rate at which carbon dioxide is removed from the cell

B4B Which molecule synthesized by plants is a major source of energy for cellular processes in both plants and animals?

• Wax

• Nucleic acid

• Glucose

• Chlorophyll

Which cellular process takes place in the ribosomes that are bound to the endoplasmic reticulum?

• The breakdown of waste material

• The conversion of radiant energy to glucose

• The synthesis of new proteins

• The replication of nucleic acids

B4B The picture shows a contractile vacuole of a unicellular freshwater organism. The contractile vacuole regulates the flow of water into and out of the cell in an aquatic environment.

What conditions cause the contractile vacuole to fill with water?

• The concentration of water is greater outside the cell than inside the cell.

• The temperature of water in the vacuole is higher than the temperature of its environment .

• The concentration of water inside the cell is the same as the concentration outside the cell.

• The temperature of water in the vacuole is lower than the temperature of its environment

B4B In the early 1900s a scientist hypothesized a link between DNA and the production of proteins in the cytoplasm. However, the fact that DNA could not be found outside the nucleus led scientists to believe that another substance was also involved in the synthesis of protein in the cytoplasm. In the 1940s scientists performed an experiment that ultimately identified the site of protein synthesis. They also identified the molecule responsible for transporting

information from the nucleus to the site of protein synthesis. What was this newly identified molecule?

• A gene

• mRNA

• ATP

• Thymine

B4B This diagram shows cellular activity across a cell membrane. Which two processes does this diagram most directly model?

• Energy conversions and synthesis of new molecules

• Synthesis of new molecules and homeostasis

• Transport of molecules and energy conversions

• Homeostasis and transport of molecules

B4B Cells can generate as many as 36 to 38 molecules of adenosine triphosphate (ATP) from the metabolism of one molecule of glucose. Which cellular process results in this amount of ATP production?

• Anaerobic cellular respiration

• Protein synthesis

• Aerobic cellular respiration

• Photosynthesis

B4B Some students used vinegar to dissolve away the shells of three eggs and used these eggs as models of human red blood cells. The students observed the changes in the eggs when they were placed in different solutions.

Which statement best describes the role of the cell membrane in this model?

• The cell membrane is an impermeable barrier that prevents water from entering the cell.

• The cell membrane allows solutes to enter the cell, which causes the cell to shrink.

• The cell membrane allows water to enter and leave the cell.

• The cell membrane removes solutes from the environment

B4B Which group of organelles is directly responsible for the production of new molecules with in a cell?

• Ribosomes, the endoplasmic reticulum, and Golgi apparatuses

• Golgi apparatuses, lysosomes, and the plasma membrane

• The endoplasmic reticulum, plastids, and vacuoles

• The nucleolus, vacuoles, and ribosomes