Freshman Science Final Exam REVIEW (LONDON) Spring 2025

When designing an experiment, scientists will test a relationship between a “cause” and an “effect.” The “effect,” also represented by what the scientist measures and records, is known as the

• Dependent variable

• Constant

• Independent variable

• Control group

Answer explanation

The "effect" in an experiment is what the scientist measures, which is known as the dependent variable. It depends on the changes made to the independent variable, thus making it the correct choice.

In pea plants, Purple flowers (P) is dominant to white flowers (p). A white flowered plant would have which of the following genotypes

• Homozygous Dominant

• Homozygous Recessive

• Heterozygous

• Codominant

Answer explanation

A white flowered plant must have two recessive alleles (pp) since purple (P) is dominant. Therefore, the genotype for a white flowered plant is homozygous recessive.

Tags

NGSS.HS-LS3-1

What conclusion can be reached by the data shown in the graph above?

• The rate of photosynthesis is greatest during the months of May, June and July, and significantly less during the winter months.

• The rate of photosynthesis is lowest during the months of May, June and July, and significantly less during the winter months.

• The rate of photosynthesis remains the same all year.

• The rate of photosynthesis is greatest in January, February and March.

Answer explanation

The graph indicates that photosynthesis peaks in May, June, and July, aligning with warmer temperatures and longer daylight, while it declines significantly in winter months, confirming the correct choice.

Tags

NGSS.MS-LS1-6

NGSS.MS-LS2-3

According to the Continental Drift Theory:

• The continents were once joined together as a supercontinent. Over time, the supercontinent broke into continents that drifted apart.

• The continents are slowly drifting towards each other. Eventually, they will collide and destroy each other.

• The continents are slowly growing in size due to tectonic plate movement.

• The continents are slowly sinking down into Earth’s mantle.

Answer explanation

The correct choice explains that according to the Continental Drift Theory, continents were once a supercontinent that broke apart and drifted over time, which aligns with the theory's fundamental concept.

Tags

NGSS.HS-ESS1-5

NGSS.HS-ESS1-6

Genes for traits that help an organism be more successful reproductively can be expected to

• cause it to evolve into a new species.

• become more common in the future.

• cause the extinction of the species.

• eventually be eliminated by natural selection.

Answer explanation

Genes that enhance reproductive success are likely to increase in frequency over generations, as they provide a survival advantage. Thus, these beneficial traits can be expected to become more common in the future.

Tags

NGSS.HS-LS4-2

NGSS.HS-LS4-4

What do you call the deep valley between the mountains of a mid-ocean ridge?

• A volcano

• A canyon

• A rift

• A river

Answer explanation

The deep valley between the mountains of a mid-ocean ridge is called a rift. This geological feature forms as tectonic plates pull apart, creating a depression in the ocean floor.

Tags

NGSS.HS-ESS1-5

NGSS.HS-ESS2-1

In performing any laboratory experiment, what is the first step performed out of the following choices

• Collect data

• Analyze data

• Publish results

• Form a hypothesis

Answer explanation

The first step in any laboratory experiment is to form a hypothesis. This involves making an educated guess about the outcome of the experiment, which guides the subsequent steps like data collection and analysis.

A controlled experiment changes only one variable at a time. A student wanted to know which sugar would yield the greatest amount of energy for the cell. The student mixed yeasts in three different types of sugar solutions. Which of these is not a constant?

• The amount of sugar in each solution must be constant.

• Each beaker should receive the same amount of yeast.

• All beakers should be kept at the same temperature.

• The type of sugar should be the same in each beaker

Answer explanation

The type of sugar should be different in each beaker to test which yields the most energy. This is the variable being changed, while the other factors must remain constant to ensure a fair experiment.

Each of the following are examples of experiments that use quantitative data EXCEPT

• Determining the mass, volume and density of an object.

• Calculating the rate of a chemical reaction.

• Measuring the amount of oxygen consumed while exercising.

• Observing and sketching images of the solar eclipse

Answer explanation

The correct choice is 'Observing and sketching images of the solar eclipse' because it involves qualitative data (observations and sketches) rather than quantitative data, which involves numerical measurements.

Tags

NGSS.HS-PS1-7

NGSS.HS-PS3-1

NGSS.HS-PS3-4

Which type of seismic waves can travel across Earth?

• P waves

• S waves

• Surface waves

• All seismic waves travel at the same speed

Answer explanation

P waves, or primary waves, are compressional waves that can travel through solids, liquids, and gases, allowing them to move across the entire Earth. In contrast, S waves and surface waves cannot travel through liquids.