MORROW'S QUIZ: Variables, Water Concepts, Sea Ice, and Data Interpretation

Flashcards covering dependent/independent variables, control types, water properties (polarity, cohesion/adhesion, solvent behavior, heat capacity, density of ice), how water moves in plants, sea ice importance, and interpretation of error bars in bar graphs.

What is the difference between a dependent variable and an independent variable in an experiment?

The independent variable is the variable deliberately changed or controlled by the experimenter; the dependent variable is what is measured in response to the changes.

What is the purpose of a positive control in an experiment?

A positive control shows the experiment can produce a response when a known effect is present, confirming the test setup works.

What is the purpose of a negative control in an experiment?

A negative control shows no response when no treatment is applied, ensuring that observed effects are due to the experimental variable.

What is cohesion in water?

Cohesion is the attraction between water molecules due to hydrogen bonding, causing them to stick together.

What is adhesion in water?

Adhesion is the attraction between water molecules and other substances (e.g., cell walls), helping water move through materials.

What does polarity mean in a water molecule?

Water is a polar molecule with a partial negative charge on the oxygen atom and partial positive charges on the hydrogen atoms, enabling hydrogen bonds.

How does water move up a plant?

Water moves upward via the cohesion-tension theory and transpiration pull, aided by adhesion to xylem walls and capillary action.

Why is sea ice important for Earth's climate and ecosystems?

Sea ice insulates ocean water, increases Earth's albedo, helps regulate climate and ocean circulation, and provides habitat for polar species.

Why is water often described as a universal solvent?

Because its polarity allows it to dissolve many ionic and polar substances, enabling solvent-based biochemical reactions.

Why does water have high surface tension?

Hydrogen bonds at the surface create cohesive forces, leading to high surface tension that resists external force.

Why does water have a high heat capacity?

Hydrogen bonding absorbs and stores energy, buffering temperature changes and giving water a high specific heat.

Why does ice float on water?

Ice forms a less dense open lattice due to hydrogen bonding, causing ice to float atop liquid water.

In a bar graph with error bars, what does overlap of error bars indicate about differences between groups?

Overlap generally suggests there is no statistically significant difference at the chosen confidence level; non-overlap suggests potential significance, though depends on whether error bars represent SD or SE.