Comprehending scientific presentations

The answer comes straight from the table. In the column Resting heart rate (beats per minute), the value 100 appears in the row for Medium dog.

Step by step:

1. Read the column headings first so you know which column holds heart rates (the third column).
2. Run your finger down that column until you find 100.
3. Move left along the same row to the first column: "Medium dog".
4. Check the other choices: the cat is 150, the human is 70 and the horse is 40, so none of them match.

The correct answer is C, medium dog.

Tip: In a table, always find the right column first, then stay in one row. Many wrong answers come from sliding up or down a row by mistake.

Read the two number columns together. Going down the table, mass increases (0.02 kg → 4 → 20 → 70 → 500 → 5,000 kg) while resting heart rate decreases (600 → 150 → 100 → 70 → 40 → 30 beats per minute). The passage says the same thing in words: "larger mammals have slower resting heart rates than smaller mammals."

Step by step:

1. Check the direction of each column: mass goes up, heart rate goes down.
2. When one value rises as the other falls, the relationship is inverse (opposite directions).
3. Test each choice against the numbers. Choice B says both rise together, which the data contradict. Choice C claims a doubling rule, but going from 4 kg to 20 kg (five times heavier) the rate falls only from 150 to 100. Choice D is about lifespan, which is not in the table at all.

The correct answer is A.

Tip: Describe a relationship by its direction first ("as X goes up, Y goes down"). Reject choices that add a precise rule the numbers do not follow or that talk about data that were never shown.

The answer comes straight from the table. In the column Seeds germinated after 7 days (%), the value 70 appears in the row that begins with 15 °C.

Step by step:

1. Read the three column headings so you know which column holds the germination percentages (the middle column).
2. Run down that column until you reach 70.
3. Stay in the same row and move left to the temperature column: 15 °C.
4. Check the other choices: 10 °C gave 35%, 20 °C gave 92% and 30 °C gave 80%.

The correct answer is B, 15 °C.

Check: The row for 15 °C also shows 3 days until the first sprout, which is a different column and does not change the answer.

Tip: When a table has more than two columns, put your finger on the right column first and keep one row at a time.

Look at the whole germination column, not just one part of it: 8, 35, 70, 92, 95, 80, 40.

Step by step:

1. From 5 °C to 25 °C the percentage rises: 8 → 35 → 70 → 92 → 95.
2. From 25 °C to 35 °C the percentage falls: 95 → 80 → 40.
3. So germination rises to a peak near 25 °C and then drops at higher temperatures. This also matches the class's note that the seeds have a best range of temperatures.

The correct answer is C: germination increased as the temperature rose to about 25 °C and then decreased at higher temperatures.

Check: Choice A only describes the first five rows. Choice B is the reverse of the first five rows. Choice D ignores a clear pattern.

Tip: Before choosing a trend statement, check the first, the peak and the last values. A trend that changes direction needs a two-part description.

22 °C was not tested, so you must interpolate, which means estimate a value between two measured points.

Step by step:

1. Find the tested temperatures on either side of 22 °C: 20 °C and 25 °C.
2. Read their results: 92% at 20 °C and 95% at 25 °C.
3. A temperature between 20 °C and 25 °C should give a result between 92% and 95%. About 93% fits.

The correct answer is B, about 93%.

Check: 75% is lower than both neighbors; 99% is higher than every value in the table; 50% would only make sense near 10–15 °C or near 35 °C.

Tip: To estimate an untested value, find the two data points that 'sandwich' it. Your estimate must lie between their results unless the text gives a reason otherwise.

Read two points from the graph. At 10 °C the point is labeled 11.3 mg/L. At 30 °C the point is labeled 7.6 mg/L.

Step by step:

1. Find 10 on the x-axis (water temperature) and go up to the point: 11.3 mg/L.
2. Find 30 on the x-axis and go up to the point: 7.6 mg/L.
3. The decrease is the difference: 11.3 - 7.6 = 3.7\text{ mg/L}.
4. Check the units: the question asks about dissolved oxygen, so the answer is in mg/L, not degrees.

The correct answer is B, 3.7 mg/L.

Tip: On a graph question, say the axis names to yourself ("temperature across, oxygen up"). A choice that equals the change in the x-variable (here 20 °C) is a classic trap.

Translate the graph into words. The line goes down from left to right, so warmer water holds less oxygen. Now look at the size of the drops for each 5 °C step: 14.6 → 12.8 is a drop of 1.8; 12.8 → 11.3 is 1.5; ... 7.6 → 7.0 is only 0.6. The drops get smaller, so the line falls steeply at first and then more gradually.

Step by step:

1. Direction: down (eliminates choice A, which says it increases).
2. Rate: drops shrink from 1.8 to 0.6, so the decrease is not the same every step (eliminates choice C).
3. Choice D talks about fish needing oxygen in cold water, a claim about animals, not what the graph shows; the graph only shows how much oxygen water can hold.

The correct answer is B.

Tip: A good summary of a graph names the direction AND the shape (steady straight line, or steep-then-flat curve). Check both against the numbers.

The passage explains the model directly: "each arrow points from an organism to the organism that eats it. The arrow therefore shows the direction in which energy flows."

Step by step:

1. The arrow starts at Grasshopper and points to Frog.
2. By the rule in the passage, the organism at the arrowhead (Frog) eats the organism at the tail (Grasshopper).
3. So energy stored in the grasshopper's body moves to the frog when the frog eats it.
4. Choice A reverses the arrow. Choice C confuses a food web with a life cycle. Choice D invents a comparison of population size that the diagram does not show.

The correct answer is B: energy flows from the grasshopper to the frog when the frog eats the grasshopper.

Tip: Before answering any diagram question, find the key or the sentence that explains the symbols. In food webs, arrows point toward the eater ("goes into").

This question asks you to extrapolate, or predict beyond the last data point, using both the graph and the text.

Step by step:

1. At 40 minutes the water is 29 °C, and it is cooling more and more slowly (drops of 4, 3 and then 2 degrees per 5 minutes).
2. The passage says the water 'keeps cooling until it reaches room temperature,' which is 22 °C, and then stops changing.
3. So at 60 minutes the water should be a little cooler than 29 °C but not below 22 °C. About 25 °C fits.

The correct answer is B, about 25 °C.

Check: 10 °C and 0 °C are below room temperature, which the passage rules out. 29 °C would mean the water stopped cooling while it was still warmer than the room.

Tip: When you predict beyond a graph, look for a limit in the text (room temperature, 100%, zero). A curve that is levelling off approaches that limit; it does not keep falling in a straight line.

Every paragraph helps explain why a sea breeze forms. Paragraph 2 says 'A sea breeze begins because land and water heat up at different rates.' Paragraphs 3 and 4 describe warm air rising over land and cool air moving in from the sea in a loop the author calls a convection current. Paragraph 5 shows the same process reversed at night.

Step by step:

1. Ask: what is the passage mostly about? The cause of the sea breeze.
2. Find the sentence that combines the cause (uneven heating) and the result (cool air moving from sea to land).
3. Eliminate statements that describe only one detail or say something the passage does not.

The correct answer is D.

Check: A is a true detail from paragraph 3, but it does not mention breezes. B is too broad. C contradicts paragraph 5, where the sea is warmer than the land at night.

Tip: A main-idea answer must be true and cover the whole text. A true detail is often the most tempting wrong answer.

Scientific terms are often defined right in the passage. Paragraph 4 says: 'Scientists call this kind of loop, in which warm fluid rises and cooler fluid sinks, a convection current.'

Step by step:

1. Find the bold term in paragraph 4.
2. Read the whole sentence: the definition is 'this kind of loop, in which warm fluid rises and cooler fluid sinks.'
3. Match that definition to the choices. Only C describes a loop of rising warm fluid and sinking cool fluid.

The correct answer is C.

Check: A describes the land breeze from paragraph 5, which is one example of the loop at night, not the meaning of the term. B uses the everyday meaning of 'current' (water moving in the ocean). D describes the different heating rates from paragraph 2.

Tip: When the GED asks what a term means 'as used' in a passage, look for a definition clue nearby: commas, the words called, known as, which means, or a phrase set off with in which.

In this model every arrow points in the direction blood flows, so follow the arrow that leaves the Lungs box.

Step by step:

1. Two arrows touch the Lungs box. The blue arrow from the right side of the heart points into the lungs.
2. The dashed red arrow starts at the lungs and points down into the Left side of heart box.
3. So blood goes from the lungs straight to the left side of the heart. The key says this blood is oxygen-rich, which matches the passage: 'Blood picks up oxygen in the lungs.'

The correct answer is A, the left side of the heart.

Check: Body tissues come next, but only after the left side of the heart pumps the blood. The right side of the heart sends blood to the lungs; it does not receive blood from them.

Tip: In any flow model, follow arrows one link at a time. 'Immediately after' means the very next box, not one further along the path.

Symbols in a scientific figure are explained by its key. The key at the bottom of the diagram shows a dashed red arrow labeled 'Oxygen-rich blood', and the note says the arrows show the direction blood flows.

Step by step:

1. Find the dashed red arrow in the key: it stands for oxygen-rich blood.
2. Check the diagram: dashed red arrows run from the lungs to the left side of the heart and from the left side of the heart to the body tissues.
3. This agrees with the passage, which says blood picks up oxygen in the lungs.

The correct answer is A, the flow of oxygen-rich blood.

Check: One dashed red arrow goes toward the heart and one goes away from it, so B is wrong. Solid blue arrows show oxygen-poor blood (C). The model does not show air moving (D).

Tip: Before answering any question about a figure, read its title, labels and key. The GED often tests whether you used the key or guessed from color alone.

This question needs two readings from two different data sets on one graph.

Step by step:

1. Find the tallest blue bar. June has the most daylight, 15.5 hours (July is close at 15.2 hours).
2. Move up to the red line above June. The point is labeled 68, read on the right axis in °F.
3. So the average temperature in the month with the most daylight is 68 °F.

The correct answer is B, 68 °F.

Check: 73 °F is July, the warmest month, but July does not have the most daylight. 15.5 is June's daylight in hours, not a temperature. 8.7 is December's daylight, the least of the year.

Tip: On a two-axis graph, decide which axis goes with which data set before you read anything. Bars here use the left axis; the line uses the right axis.

This graph has two y-axes, so the question takes two steps.

Step by step:

1. Find the wettest month (bars, left axis). The tallest bar is June, reaching 4.5 inches (one gridline below 5). The next tallest is May at 4.0 inches.
2. Read June's temperature (line, right axis). The red dot for June sits on the gridline labeled 70 on the right axis, so June's average temperature is 70 °F.
3. Watch the trap: the top of the June bar lines up with 90 on the right axis. But bars must be read on the left axis only, so 90 °F is not a temperature from this graph's data.
4. July is the warmest month (75 °F), but it is not the wettest.

The correct answer is A, 70 °F.

Tip: On a dual-axis graph, match each data series with its own axis. The passage tells you: bars with the left axis, line with the right axis.

Translate each month carefully, one series at a time. Each gridline is 0.5 inch on the left axis and 10 °F on the right axis.

Step by step:

1. March: the bar reaches 3.5 inches; the red dot is on the 40 line of the right axis → 3.5 in, 40 °F.
2. April: the bar also reaches 3.5 inches; the dot is on 50 → 3.5 in, 50 °F.
3. May: the bar reaches 4.0 inches; the dot is on 60 → 4.0 in, 60 °F.
4. Now check the traps. Choice B reads the red dots against the left axis (a dot at 40 °F sits at the 2.0-inch height). Choice C reads the bar tops against the right axis (a 3.5-inch bar top lines up with 70). Choice D copies February, March and April by mistake, one month too early.

The correct answer is A.

Tip: When translating a graph into a table, work one month (one x-value) at a time and say which axis you are using. Then double-check you started on the right month.

To move data from a table onto a graph, each row becomes one point written as (x, y). Here x is the year and y is the CO₂ level.

Step by step:

1. Choose a row, for example 1990. Its CO₂ value is 354.4 ppm.
2. Write x first and y second: (1990, 354.4).
3. Check each choice against the table. Only choice A pairs a year with its own CO₂ value in the right order.

The correct answer is A, (1990, 354.4).

Check: B has the right numbers in the wrong order. C pairs 1990 with the 2000 value (369.7). D uses 1985, a year that is not in the table, even though 354.4 belongs to 1990.

Tip: When you translate a table into a graph, say the pair aloud: 'year first, value second.' Then check that both numbers come from the same row.

This is a key detail question, so the answer is stated directly in the text. Paragraph 1 says: 'The site was chosen because it is far from cities, forests and other large local sources of CO₂. As a result, the air there gives a good picture of the well-mixed air of the Northern Hemisphere.'

Step by step:

1. Find the signal word because in paragraph 1.
2. Read the reason: the site is far from local CO₂ sources, so its air represents the wider atmosphere.
3. Match this reason to the choices. Choice D says the same thing in different words.

The correct answer is D.

Check: A is the opposite of the text, which says the site is far from forests and cities. B mentions plants, but the passage uses plants to explain the seasonal rise and fall, not the choice of site. C is never stated.

Tip: For 'according to the passage' questions, find the exact sentence. Wrong answers often reuse words from the passage (forests, plants) in a way the passage did not.

Read each mass on the x-axis and the matching stretch on the y-axis.

Step by step:

1. 100 g → 2.5 cm (halfway between the 2 and 3 cm gridlines).
2. 300 g → 7.5 cm.
3. 500 g → 12.5 cm.
4. Only choice B lists all three pairs correctly.

The correct answer is B.

Check: A reads every value too low (for example, 10.0 cm instead of 12.5 cm at 500 g). C keeps the correct first pair but then uses the values for 200 g and 300 g. D swaps the columns, writing stretch values as masses.

Tip: When you match a table to a graph, test every row. Distractors often get the first value right and slip on the next ones.

The passage defines the term and then tells you what happens when it is exceeded: the elastic limit is 'the largest load a spring can hold and still return to its original shape,' and 'If a spring is loaded beyond its elastic limit, it stays permanently stretched.'

Step by step:

1. Use the definition: within the elastic limit, the spring goes back to its original length when the load is removed.
2. Use the next sentence: beyond the limit, the spring stays permanently stretched.
3. So the sign of passing the limit is that the spring stays longer than its original length after the masses are removed.

The correct answer is C.

Check: A describes what happens within the limit (the student's own results). B is just the normal straight-line pattern in the graph. D describes a spring returning to its original shape, which means it was not overloaded.

Tip: When a passage defines a term, the definition plus the sentence right after it usually tell you how to recognize it in a new situation.

This value requires two conditions: the row for freezing and the column for tun-state animals.

Step by step:

1. Find the row 'Frozen at −20 °C for 30 days.'
2. Find the column 'Tun-state tardigrades surviving (%)', the third column.
3. Where they meet, the value is 91.

The correct answer is C, 91%.

Check: 72% is in the same row but the active-tardigrade column. 88% is in the tun-state column but the 60 °C heating row. 96% is the tun-state value for the comparison group kept in water.

Tip: For a two-way table, trace the row with one finger and the column with another. The answer is where they meet. Wrong choices on the GED are usually the neighboring cells.

The main finding should be supported by all of the data and match the researchers' conclusion: 'entering the tun state greatly improves a tardigrade's chances of surviving extreme heat and cold.'

Step by step:

1. Compare the columns in each harsh condition: freezing 72% vs. 91%, 60 °C 15% vs. 88%, 90 °C 0% vs. 54%. Tun-state survival is higher every time.
2. In the comparison group (98% vs. 96%) both groups survive well, so the big difference appears only under harsh conditions.
3. The best summary is that the tun state helps tardigrades survive extreme temperatures much better than active tardigrades.

The correct answer is A.

Check: B is too absolute: 46% of tun-state animals died at 90 °C. C is one true detail (active animals at 90 °C), not the main finding. D is not tested: the study covered only heat and cold, not space or every condition.

Tip: A good summary of an experiment compares the groups the way the researchers did and does not go beyond the conditions tested.