GED Science Practice Test 3

Which of the following statements is accurate based on the line graph representing the total renewable energy consumed by the residential and commercial sectors from 2010 to 2022?

U.S. Virologic Surveillance

Nationally, the percentage of respiratory specimens testing positive for influenza in clinical laboratories decreased (change of ≥0.5 percentage points) compared to the previous week. The regions with the highest percent positivity were regions 6 (22.7%), 8 (22.4%), 3 (18.8%), and 4 (15.0%). Since Week 40, influenza A(H1N1)pdm09 has been the predominant virus circulating in all regions. However, the distribution of circulating viruses varies by region. For regional and state level data and age group distribution, please visit FluView Interactive. Viruses known to be associated with recent receipt of live attenuated influenza vaccine (LAIV) or found upon further testing to be a vaccine virus are not included, as they are not circulating influenza viruses.

Clinical Laboratories

The results of tests performed by clinical laboratories nationwide are summarized below. Data from clinical laboratories (the percentage of specimens tested that are positive for influenza virus) are used to monitor whether influenza activity is increasing or decreasing.

Which of the following statements about the data’s probability and sampling is correct?

Pedigrees:

One can record a family history in several ways, including charts, checklists, forms, and drawings of a family tree or “pedigree.” Pedigrees are sometimes the preferred method of collecting family history information because a pedigree can be drawn more quickly than the information can be written and allows patterns of disease to emerge as it is drawn. A pedigree represents family members and relationships using standardized symbols. Because the family history continually changes, the pedigree can be updated easily on future visits. Patients should be encouraged to record information and update their family histories regularly.

Consider a pedigree chart showing the inheritance of a specific genetic trait for a specific family.

The Punnett square for this would look like:

What is the probability that their first child will inherit the trait (aa)?

Breakdown of Pyruvate

In order for pyruvate, the product of glycolysis, to enter the next pathway, it must undergo several changes. The conversion is a three-step process.

Step 1: A carboxyl group is removed from pyruvate, releasing a molecule of carbon dioxide into the surrounding medium. The result of this step is a two-carbon hydroxyethyl group bound to the enzyme. This is the first of the six carbons from the original glucose molecule to be removed. This step proceeds twice (remember: there are two pyruvate molecules produced at the end of glycolsis) for every molecule of glucose metabolized; thus, two of the six carbons will have been removed at the end of both steps.

Step 2: The hydroxyethyl group is oxidized to an acetyl group, and the electrons are picked up by NAD+, forming NADH. The high-energy electrons from NADH will be used later to generate ATP.

Step 3: The enzyme-bound acetyl group is transferred to CoA, producing a molecule of acetyl CoA.

Which of the following statements provides the most accurate claim and evidence about the breakdown of pyruvate in the context of cellular respiration?

What are the major milestones in human evolution?

The human lineage diverged from that of apes at least seven million years ago and maybe as long as 13 million years ago. The earliest undisputed members of our lineage to regularly walk upright were the australopithecines, of which the most famous is Lucy’s species, Australopithecus afarensis. (Lucy herself is dated to 3.2 million years ago.) The oldest known fossil attributed to our genus, Homo, dates to about 2.8 million years ago and was reported just this year. The ability to make stone tools was once thought to be the hallmark of our genus. But the oldest stone tools are now thought to be 3.3 million years old. Either they were made by australopithecines like Lucy—or scientists simply haven’t yet found the early form of Homo that made them. Like australopithecines, early Homo species, such as H. erectus and H. habilis, walked on two legs.

There’s considerable debate over when our ancestors first harnessed fire—it may have been anywhere from 1.8 million to around 800,000 years ago. According to one theory, the invention of cooking allowed us to gain more energy from meat, which fueled the dramatic evolution of the human brain. Bigger brains and more dexterous hands in turn were the prerequisite for the developments that set humans apart, including complex language, art, and agriculture, all of which emerged in the past 100,000 years.

Where did all this happen, and why does it matter where?

Both genetic and fossil evidence show that until relatively recently, human evolution happened in Africa. Whether the genus Homo first emerged in southern or in eastern Africa remains unclear. Knowing where our species evolved matters because the environment it adapted to helped shape the genetic makeup we still carry with us today. Where we came from is the first chapter in the long story of how we got to where we are now.

Around 60,000 years ago—again according to both genetic and fossil evidence—modern humans migrated out of Africa and began colonizing the world. Genetic evidence suggests that soon after leaving Africa, they interbred to some extent with the Neanderthals and a mysterious population in Asia called the Denisovans. Homo sapiens is now the only species of human on Earth. But that’s been true for less than 30,000 years.

Which of the following represents the accurate chronological sequence of key events in human evolution and migration, considering both genetic and fossil evidence?

Common Health-Promoting Dietary Patterns

Based on our understanding of nutritional requirements and their likely health impacts, healthy dietary patterns can be generally described as those that are rich in health-promoting foods, including plant-based foods, fresh fruits and vegetables, antioxidants, soya, nuts, and sources of omega-3 fatty acids, and low in saturated fats and trans fats, animal-derived proteins, and added/refined sugars.

Patterns such as these are naturally occurring in certain regions of the world and rooted in local/regional tradition and food sources, as is the case for the traditional Mediterranean and Asian diets. Healthy dietary patterns have also been developed based on studies of nutrient intake and subsequent health measures or outcomes that share some common characteristics.

Which of the following strategies could contribute to a healthier lifestyle?

I. Implementing a diet rich in diverse fruits, vegetables, and whole grains.
II. Advocating for the consumption of processed foods high and sugary treats.
III. Encouraging regular physical exercise to enhance metabolic processes.
IV. Promoting the increase of water intake.

A team of researchers aims to investigate the potential impact of chemical properties and reactions on human systems. They design a complex experiment to explore the interaction between a newly synthesized chemical compound (Compound X) and a specific human cellular process.

In this experiment, three groups of human cells are exposed to varying concentrations of Compound X for different durations. The researchers measure multiple parameters, including cell viability, gene expression profiles, and metabolic activity, at different time points. Additionally, they conduct control experiments with untreated cells to establish baseline values.

The researchers hypothesize that Compound X may influence a critical cellular pathway implicated in human disease. To test this hypothesis, they employ cutting-edge molecular techniques to analyze the intricate molecular changes induced by Compound X.

After months of meticulous experimentation, the research team gathers a vast dataset comprising quantitative and qualitative results. The data exhibit intricate trends and patterns, making the interpretation challenging.

Additional Information About the Experiment:

• Dependent Variables (What is being measured): Cell viability, gene expression profiles, and metabolic activity.
• Independent Variables (What is being changed): Concentration of compound X and duration of exposure to compound X.

What is the role of the control experiments conducted by the research team in the described experiment?

The Carbon Cycle

Carbon is a fundamental part of the Earth system. It is the backbone of life on Earth. We are made of carbon, we eat carbon, and our civilizations—our economies, our homes, our means of transport—are built on carbon. Forged in the heart of aging stars, carbon is the fourth most abundant element in the Universe. Most of Earth’s carbon—about 65,500 billion metric tons—is stored in rocks. The rest is in the ocean, atmosphere, plants, soil, and fossil fuels. Carbon moves from the atmosphere to the land, ocean, and life through biological, chemical, geological and physical processes in a cycle called the carbon cycle. Any change in the cycle that shifts carbon out of one reservoir puts more carbon in the other reservoirs. Carbon flows between each reservoir in slow and fast cycles.

This diagram of the fast carbon cycle shows the movement of carbon between land, atmosphere, and oceans. Yellow numbers are natural fluxes, and red are human contributions in gigatons of carbon per year. White numbers indicate stored carbon.

Over the long term, the carbon cycle seems to maintain a balance that prevents all of Earth’s carbon from entering the atmosphere (as is the case on Venus) or from being stored entirely in rocks. This balance helps keep Earth’s temperature relatively stable, like a thermostat. This thermostat works over a few hundred thousand years, as part of the slow carbon cycle. This means that for shorter time periods—tens to a hundred thousand years—the temperature of Earth can vary. And, in fact, Earth swings between ice ages and warmer interglacial periods on these time scales. Parts of the carbon cycle may even amplify these short-term temperature changes.

Considering the intricacies of the carbon cycle, what is the correct sequence of events in the movement of carbon among various reservoirs?

Did age-specific death rates in 2021 change from 2020 for those aged 1 year and over?

From 2020 to 2021, death rates increased for each age group 1 year and over (Figure 3). Age-specific rates increased 10.1% for age group 1–4 (from 22.7 deaths per 100,000 population in 2020 to 25.0 in 2021), 4.4% for 5–14 (13.7 to 14.3), 5.6% for 15–24 (84.2 to 88.9), 13.4% for 25–34 (159.5 to 180.8), and 16.1% for 35–44 (248.0 to 287.9).

Rates increased 12.1% for 45–54 (473.5 to 531.0), 7.5% for 55–64 (1,038.9 to 1,117.1), 3.8% for 65–74 (2,072.3 to 2,151.3), 2.4% for 75–84 (4,997.0 to 5,119.4), and 3.5% for 85 and over (15,210.9 to 15,743.3).

What general conclusion can we come to by using the data above?

Humans have well-developed muscles in the face that permit a large variety of facial expressions. Because the muscles are used to show surprise, disgust, anger, fear, and other emotions, they are an important means of nonverbal communication. Muscles of facial expression include frontalis, orbicularis oris, laris oculi, buccinator, and zygomaticus. These muscles of facial expressions are identified in the illustration below.

There are four pairs of muscles that are responsible for chewing movements or mastication. All of these muscles connect to the mandible and they are some of the strongest muscles in the body. Two of the muscles, temporalis and masseter, are identified in the illustration above.
There are numerous muscles associated with the throat, the hyoid bone and the vertebral column; only two of the more obvious and superficial neck muscles are identified in the illustration: sternocleidomastoid and trapezius.

Which pair of muscles, responsible for chewing movements or mastication, are identified in the given illustration?

An ecologist conducted a study to examine the impact of a new predator introduced into an ecosystem on the population of a prey species. The ecologist collected data on the prey population over time.

The graph below illustrates the relationship between time (x-axis) and prey population (y-axis).

Based on the provided graph, at which point in time did the prey population experience the highest decline?

The Work–Energy Theorem

In physics, the term work has a very specific definition. Work is application of force, f, to move an object over a distance, d, in the direction that the force is applied. Work, W, is described by the equation W = fd.

Some things that we typically consider to be work are not work in the scientific sense of the term. Let’s consider a few examples. Think about why each of the following statements is true.

• Homework is not work.
• Lifting a rock upwards off the ground is work.
• Carrying a rock in a straight path across the lawn at a constant speed is not work.

The first two examples are fairly simple. Homework is not work because objects are not being moved over a distance. Lifting a rock up off the ground is work because the rock is moving in the direction that force is applied. The last example is less obvious. Recall from the laws of motion that force is not required to move an object at constant velocity. Therefore, while some force may be applied to keep the rock up off the ground, no net force is applied to keep the rock moving forward at constant velocity.

A group of students conducted an experiment to investigate the relationship between the force applied to an object and the resulting work done. They measured the force applied (in Newtons) and the corresponding work done (in Joules) and recorded their observations in the table below:

​The students plotted a graph with force on the x-axis and work done on the y-axis. They most likely obtain a (choose a, b, or c) graph with a (choose d, e, or f) slope.

Researchers conducted an experiment to investigate the effects of a newly discovered substance, Xylozyme, on human metabolism. They recruited two groups of participants: Group A and Group b. Group A received a daily dose of Xylozyme for six weeks, while Group B received a placebo. Both groups were subjected to the same controlled diet and exercise regimen throughout the study.

At the end of the experiment, the researchers observed significant changes in metabolic rates among individuals in Group A compared to those in Group b. However, the researchers want to ensure the validity of their findings.

Which of the following actions would BEST contribute to the validity of the experiment’s results?

The following table shows the energy content and consumption rates within an aquatic ecosystem:

On plotting the energy content (Joules) against the daily consumption rate(kg/day) on the following graph, which point would represent the energy content and daily consumption rate of the 3^rd trophic level?

The Hardy-Weinberg principle, is a crucial concept in population genetics. It predicts how gene frequencies will be inherited from generation to generation given a specific set of assumptions.

The Hardy-Weinberg principle states that in a large randomly breeding population, allelic frequencies will remain the same from generation to generation assuming that there is no mutation, gene migration, selection, or genetic drift. This principle is important because it gives biologists a standard from which to measure changes in allele frequency in a population.

Hardy-Weinberg Equation:

1 = p² + 2pq + q²

Notes About Equation:

• p² represents the frequency of the homozygous dominant genotype (AA)
• 2pq represents the frequency of the heterozygous genotype (Aa)
• q² represents the frequency of the homozygous recessive genotype (aa)
• p is the frequency of the dominant allele (A)
• q is the frequency of the recessive allele (a)

Consider a case study examining the inheritance of a specific genetic trait in a population. In a cohort of 1000 individuals, a gene variant associated with the trait of interest is being studied. Analysis reveals that 40% of the individuals carry the dominant allele (A), while 60% carry the recessive allele (a) for this particular gene.

Assuming Hardy-Weinberg equilibrium, what is the probability that two randomly chosen individuals from this population are both homozygous dominant (AA) for this gene variant?

In a plant species, flower color is determined by two alleles: the allele for red color (R) is incompletely dominant over the allele for white color (r). When heterozygous, the flower color is pink. A gardener crosses two pink-flowering plants.

The Punnet Square is listed below:

Notes:

• RR = Red
• Rr = Pink
• rr = White

What is the probability that the offspring from these pink-flowering plants will have red flowers?

An object undergoes motion along a straight line under the influence of a varying force. As it moves, the following observations are recorded:

(1) Initially at rest, the object begins to accelerate uniformly,
(2) The acceleration continues until the object reaches a maximum speed,
(3) Eventually, the object decelerates uniformly and comes to a stop.

Which of the following graphs most likely represents the relationship between force and displacement experienced by the object during this motion?

Patterns of Inheritance:

Inheritance, the transmission of genetic characteristics from parents to offspring, follows various patterns determined by the underlying genetic mechanisms. Gregor Mendel, often regarded as the father of modern genetics, discovered fundamental patterns of inheritance through his experiments with pea plants in the 19th century. One of his key findings was the concept of dominant and recessive traits. In Mendelian inheritance, certain traits are dominant over others.

When an organism carries two different versions of a gene (heterozygous), the dominant allele masks the expression of the recessive allele. This results in the dominant trait being observable in the offspring’s phenotype. Additionally, Mendel observed segregation and independent assortment of alleles during gamete formation. Alleles segregate randomly during meiosis, ensuring that each gamete receives only one allele for a particular trait.

Furthermore, the principle of independent assortment indicates that alleles for different traits assort independently during gamete formation, provided the genes are located on different chromosomes. Other patterns of inheritance include codominance, where both alleles are expressed equally in the heterozygous condition, and incomplete dominance, where a blending of traits occurs in the heterozygous state.

Moreover, some traits follow sex-linked inheritance, where the gene responsible for the trait is located on one of the sex chromosomes and shows distinct inheritance patterns between males and females. Understanding these diverse patterns of inheritance provides insights into the transmission of genetic traits across generations and forms the basis for genetic studies in various organisms.

Sarah conducted an experiment to investigate the inheritance of a specific trait in a population of fruit flies. She crossed two fruit flies with different traits: one exhibiting red eyes (RR) and another with white eyes (rr). All their offspring had red eyes. In a subsequent generation, Sarah crossed two of these red-eyed flies and obtained a ratio of 3:1 red eyes to white eyes in their offspring.

Based on these results, which of the following best represents the inheritance pattern Sarah observed for the eye color trait in the fruit flies?

When an object rests on an inclined plane, the force due to gravity can be resolved into two components: one parallel to the plane (the force that tends to slide the object down the incline) and the other perpendicular to the plane (the force pressing the object against the surface of the incline). The force that tends to move the object down the incline is proportional to the sine of the angle of inclination.

Mathematically, the force parallel to the incline F_{parallel} can be expressed as:

F_{parallel} = force due to gravity * sin

Sophia conducted an experiment to investigate the relationship between the angle of inclination and the force required to move an object up an inclined plane. She used a wooden block of known mass and altered the angle of the inclined plane, measuring the force needed to move the block at different angles.

Analyzing Sophia’s experiment with the inclined plane and the block’s movement, which statement accurately describes the trend between the angle of inclination and the force required to move the block?

The following table describes various facets of ecosystems. It provides a comprehensive overview, showcasing how these terms correlate with aspects like biodiversity, trophic dynamics, pollutant accumulation, and nutrient availability within ecosystems.

A farmer accidentally had some of his runoff enter a freshwater system. 6 months later, the ecosystem was showing signs of low levels of nitrogen.

How has the ecosystem changed due to the agricultural runoff into the freshwater system?