1. 1. A chemist leaves an open dish of water at 25°C on a lab bench, well below its 100°C boiling point, and records that the water level in the dish drops noticeably over several hours as molecules escape from the liquid's surface into the air. What term describes this surface-level vaporization occurring below the boiling point?

   A.CondensationB.DepositionC.EvaporationD.Sublimation

2. 2. When a strip of magnesium metal is ignited, it combines with oxygen in the air to form magnesium oxide, a powdery substance with properties very different from the original metal. What type of change does this describe?

   A.A chemical changeB.A physical changeC.A phase changeD.A nuclear change

3. 3. A cell biologist treats a muscle cell sample with a poison that specifically disables one organelle, and within minutes the cell's ATP production drops by more than 90%, even though oxygen and glucose remain abundant. Which organelle has most likely been disabled?

   A.NucleusB.MitochondrionC.Golgi apparatusD.Ribosome

4. 4. Astronomers detect a small body of ice, dust, and rock entering the inner solar system on a long, elongated orbit from far beyond Neptune. As it approaches the Sun and warms, its icy surface begins to turn directly into gas. Which of the following best identifies this object?

   A.A star nearing the end of its life cycleB.A body of ice and dust that develops a glowing tail as it nears the SunC.A rocky body that orbits mainly between Mars and JupiterD.A large cloud of interstellar gas and dust

5. 5. A cell biologist uses a fluorescent tag to follow a newly made protein inside a cell and observes it move from the endoplasmic reticulum into a stack of flattened membranes, where it is modified and packaged into a vesicle before being shipped to its final destination. Which organelle is shown performing this packaging and shipping role?

   A.MitochondrionB.LysosomeC.NucleusD.Golgi apparatus

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