Biology EOC Practice Test #1

Prophase (chromosomes condense & nuclear membrane disappears)
Metaphase (chromosomes line up in the MIDDLE)
Anaphase (chromosomes are pulled APART)
Telophase (2 nuclear membranes form & cytokinesis occurs

The average number of eggs laid per day over the 5 days is 10. This can be calculated by summing up the number of eggs laid each day (5 + 10 + 25 + 50 = 90) and then dividing it by the number of days (90 / 5 = 18). Therefore, the average number of eggs laid per day is 18.

Urine has a pH of 6.0, which indicates that it is slightly acidic. However, compared to the other options given, urine has the highest pH value. Rainwater has a pH of 5.5, indicating that it is slightly more acidic than urine. Tomato juice and gastric juice both have a pH of 2.0, indicating that they are highly acidic. Therefore, among the given options, urine has the greatest concentration of hydroxide ions (OH-).

Early autotrophs had an advantage over early heterotrophs because they were able to produce their own food. Autotrophs are organisms that can synthesize organic compounds from inorganic substances, such as carbon dioxide and sunlight, through processes like photosynthesis. This ability allowed them to obtain energy and nutrients directly from their environment, without relying on consuming other organisms. In contrast, heterotrophs rely on consuming other organisms or organic matter for their energy and nutrient needs. By being able to produce their own food, autotrophs had a more reliable and independent source of sustenance, giving them an advantage in survival and reproduction.

Based on the graph, the elephant is approximately 1/3 as fast as the cheetah. The graph shows that the cheetah has the highest average fastest speed among the animals. By comparing the position of the elephant on the graph to the cheetah, it can be observed that the elephant's speed is approximately 1/3 of the cheetah's speed. Therefore, the elephant is the correct answer.

An individual with albinism has a genotype of homozygous recessive. This means that both copies of the gene responsible for pigmentation are non-functional, resulting in the absence of pigment in the skin.

The basic assumption of science that Ella is operating under is that nature is orderly. This means that there is a consistent and predictable pattern to natural phenomena, such as the setting of the sun and the occurrence of a full moon. By stating that the sun will set at 6:30 p.m. and there will be a full moon on Thursday night, Ella is implying that these events follow a regular and predictable schedule, which aligns with the assumption that nature is orderly.

The given answer correctly states that Lysine (Lys) in Person A is replaced with Glutamic Acid (Glu) in Person B. This is because there is a difference of one nucleotide between their mRNA sequences, specifically the nucleotide "U" in Person A is replaced with "G" in Person B. This change in the mRNA sequence leads to a different codon being formed, resulting in a different amino acid being incorporated into the protein.

The Golgi apparatus is responsible for processing and packaging cellular materials prior to export. It contains smooth-sided channels called cisternae that help in modifying and sorting proteins and lipids received from the endoplasmic reticulum. This organelle plays a crucial role in the secretion of proteins, lipids, and other cellular materials to their appropriate destinations within and outside the cell.

The experiment's results support Paul's statement because exercise increases both the pulse and the systolic pressure. The table shows that after running in place for 5 minutes, both Paul and Simon experienced an increase in their pulse rates and systolic pressures. This indicates that the heart is pumping more blood during exercise compared to when they are at rest.

The fossil record indicates that the size of horses increased over time. This suggests that larger horses had a slight advantage in terms of survival and reproduction. They were able to produce a slightly greater number of surviving offspring compared to smaller horses. This led to a gradual increase in the overall size of the horse population over generations.

The example that best illustrates the process of natural selection is when giraffe necks varied in length, and the shorter-necked giraffes were at a disadvantage. This is because natural selection involves the survival and reproduction of individuals with traits that are better suited for their environment. In this case, the shorter-necked giraffes would have a harder time reaching food and may struggle to survive, while the longer-necked giraffes would have an advantage and be more likely to pass on their genes to the next generation.

In order to determine whether temperature affects the rate at which mold grows on bread, it is important to have a control group that is subjected to the same conditions as the experimental group, except for the variable being tested (temperature in this case). Placing another piece of bread in a closed Petri dish on the countertop serves as the best comparison because it allows for the bread to be exposed to the same environmental conditions (such as humidity and air quality) as the bread in the refrigerator, but without the temperature difference. This will help to isolate the effect of temperature on mold growth.

This experimental design would provide scientists with the best data for investigating which type of feed yields the greatest gain in lean muscle mass in cattle. By testing 5 similar groups of cows with 5 different feed mixtures, the researchers can compare the weight gain of each group and determine which feed mixture leads to the greatest increase in lean muscle mass. This design controls for the variability in cow types and allows for a direct comparison between the different feed mixtures. Additionally, measuring weight gain at the end of a 6-week trial provides a consistent and measurable outcome for evaluating the effectiveness of each feed mixture.

To determine whether temperature influences the population size of Paramecium, it is necessary to compare the growth of Paramecium at different temperatures. By repeating the procedures described using 2 flasks and incubating one flask at 15oC and the other at 25oC, we can observe the population size of Paramecium under different temperature conditions. This will allow us to analyze the effects of temperature on the growth rate and population size of Paramecium.

Organic compounds are distinguished from inorganic compounds by the presence of carbon. Carbon is a unique element that has the ability to form covalent bonds with other elements, including itself, to create a wide variety of complex molecules. This characteristic allows carbon-based compounds to have a vast array of structures and functions, making them essential for life processes. In contrast, inorganic compounds do not contain carbon and are typically simpler in structure. Therefore, the key factor that separates organic compounds from inorganic compounds is the presence of carbon.

Directional selection is occurring in this cricket population. This is because the trait of having flat wings, which prevents the crickets from singing and being detected by parasitic flies, has increased in frequency over time. This suggests that there is a selective advantage for crickets with flat wings, leading to a directional shift in the population towards this trait.

The most accurate conclusion about the growth rate of the bacteria is that the 30-day old culture grows faster regardless of the strain. This can be inferred from the information given in the question, where in both experiments, the 30-day old culture consistently shows more bacterial colonies compared to the new culture. This suggests that the older culture has a higher growth rate, regardless of the strain being used.

The scatterplot shows a positive relationship between height and weight, indicating that as height increases, weight also tends to increase.

The electron transport chain is responsible for generating the majority of ATP during cellular respiration. This process occurs in the inner membrane of the mitochondria and involves the transfer of electrons through a series of protein complexes. As the electrons move through the chain, they create a proton gradient, which is used to generate ATP through oxidative phosphorylation. This process is highly efficient and produces a large amount of ATP compared to glycolysis and the Krebs cycle. Fermentation, on the other hand, does not generate ATP through the electron transport chain but rather through substrate-level phosphorylation.

Metaphase I = homologous chromosomes are pulled to the middle of the cell

In a dihybrid cross, the genotype of the F1 individuals is AaBb x AaBB. This means that one parent is heterozygous for both traits (AaBb) and the other parent is heterozygous for one trait and homozygous dominant for the other (AaBB). When these individuals are crossed, the possible genotypes of the F2 generation are AaBb, AaBB, AABb, and AABB. Since AaBb is one out of the four possible genotypes, the expected ratio of AaBb individuals in the F2 generation is 1/4 or 4/16.

The correct answer is community because a community refers to all the different species that interact and live together in a particular area. In this scenario, the barnyard grass, other weeds, rice, and insects are all different species that exist and interact with each other in the same environment.

The statement "They produce fertile offspring" most likely indicates that the two populations of animals are the same species. This is because the ability to produce fertile offspring is a key characteristic of members of the same species. If two populations can successfully mate and produce offspring that can also reproduce, it suggests that they share enough genetic similarity to be considered the same species. The other statements, such as inhabiting the same general area, having a similar outward appearance, or consuming the same type of diet, may be indicators of similarity but do not necessarily confirm that the populations are the same species.

If both parents are heterozygous, they would have one dominant and one recessive allele for coat color. This would explain why they produced both black and albino offspring. The black offspring would inherit the dominant allele from the heterozygous parents, while the albino offspring would inherit the recessive allele.

A scientific theory is the best definition of a scientific theory because it provides an explanation of how and why a natural phenomenon behaves the way it does. It goes beyond a mere description of an invariable relationship and is not simply a speculation or guess. A scientific theory is also not an unproven fact, as it is based on extensive research, evidence, and experimentation.

Lydia conducted her investigation to answer the question of how the chemistry of the soil affects the color of hydrangea blossoms. She noticed that the hydrangeas in Container 1 had pink blossoms, while those in Container 2 had blue blossoms. She made sure they all received the same amount of light and water, and her boss informed her that they were all grown from the same seed variety. After testing the soil, she discovered that the soil in Container 1 had a pH of 6.0, while the soil in Container 2 had a pH of 5.0. This suggests that the acidity of the soil, indicated by its pH level, affects the color of the hydrangea blossoms.

Color blindness is a recessive trait that is carried on the X chromosome. In this scenario, the mother is a carrier of the color-blindness allele (Xb) and the father does not carry the allele. Since the father does not carry the allele, he cannot pass it on to any of his children. However, since the mother is a carrier, there is a 50% chance that any daughter they have could be color blind, as daughters inherit one X chromosome from each parent. Therefore, a color-blind daughter is a possible outcome.

Cyclohexamide is a protein synthesis inhibitor that specifically targets the ribosomes, the organelles responsible for protein synthesis. By adding cyclohexamide to the cells and observing the formation of short incomplete protein segments, Naomi can conclude that the drug is interfering with the ribosomes' ability to synthesize proteins. Therefore, the correct answer is ribosome.

The most appropriate unit of measure for Chan to use in determining the mass of fungus growing on a nutrient agar plate over an 8-hour period would be milligram. Milligram is a smaller unit of measure compared to kilogram and kilometer, and it is commonly used to measure small masses. Since the mass of the fungus is expected to be relatively small, milligram would provide a more precise and accurate measurement for Chan's experiment.

Round eye shape is a recessive trait. This is indicated by the fact that Jeanine inherited 2 alleles for round eye shape and has round eye shape, while her brother inherited 1 allele for round eye shape and 1 allele for almond eye shape and has almond eye shape. In genetics, a recessive trait is only expressed when an individual has two copies of the recessive allele.

This example best illustrates Mendel's law of independent assortment because it shows the inheritance of two different traits (height and flower color) that are independently inherited. The fact that the offspring include tall white-flowered pea plants indicates that the traits for height and flower color have segregated independently during the formation of gametes and have recombined in the offspring. This is consistent with Mendel's law of independent assortment, which states that different traits are inherited independently of each other.

The genotype for Individual 1 in the diagram is Aa. This is because the disorder is determined by 2 alleles at 1 locus, and Individual 1 has a combination of both dominant (A) and recessive (a) alleles.

Papain is a protease enzyme, which means it helps in the digestion of proteins. It breaks down proteins into smaller peptides and amino acids, making them easier to absorb and utilize by the body. Therefore, papain aids in the digestion of proteins present in Jenna's favorite breakfast food, papaya.

The second test should be conducted with 1 mL of enzyme suspension incubated at 37oC for 20 min. This is because Edison wants to accurately test the effects of temperature on starch digestion. By increasing the temperature to 37oC, he is testing a higher temperature than the initial test at 25oC. By keeping the enzyme suspension volume and incubation time the same as the initial test, he is isolating the variable of temperature to determine its specific effect on starch digestion.

During yeast respiration, glucose is broken down in the absence of oxygen, leading to the production of ethanol, carbon dioxide, and ATP. The presence of ethanol in the yeast culture indicates that fermentation has occurred. Fermentation is an anaerobic process that converts glucose into ethanol and carbon dioxide, while ATP is produced as an energy source for the yeast cells. Therefore, the yeast culture also contains carbon dioxide and ATP.

The most likely explanation for the cell's gain in mass is that the solution is hypotonic to the cell. In a hypotonic solution, the concentration of solutes is lower outside the cell compared to inside the cell. As a result, water moves into the cell through osmosis, causing the cell to swell and gain mass.

Enzymes speed up chemical reactions by reducing activation energy. Activation energy is the energy required to start a chemical reaction. Enzymes lower this energy barrier, allowing reactions to occur more easily and quickly. They do this by binding to the reactant molecules and bringing them closer together, facilitating the formation of new bonds and the breaking of existing bonds. By reducing activation energy, enzymes increase the rate at which reactions proceed, making them essential for biological processes.

Chloroplasts are the organelles responsible for photosynthesis in plants and algae. Therefore, their presence indicates that cells are capable of photosynthesis. Since the question asks for the structure that indicates cells are NOT photosynthetic bacteria, the correct answer is chloroplast.

The molecules move into the cell through the channel protein because facilitated diffusion is a passive process that allows molecules to move across the cell membrane with the help of specific channel proteins. These channel proteins create a pathway for the molecules to pass through the hydrophobic phospholipid bilayer, which would otherwise be impermeable to them. Therefore, the molecules move into the cell through the channel protein.

DNA and RNA both contain purine bases, which are a type of nitrogenous base. Purine bases include adenine (A) and guanine (G). These bases are responsible for the genetic information stored in DNA and RNA molecules. They form hydrogen bonds with their complementary bases (thymine (T) in DNA, and uracil (U) in RNA) to maintain the double-stranded structure of DNA and the single-stranded structure of RNA. Therefore, the similarity in purine bases is a significant structural similarity between DNA and RNA.

The functional group -NH2, also known as the amino group, is absent from monosaccharides, polysaccharides, fatty acids, and glycerol. This group is characteristic of amino acids, which are the building blocks of proteins. Monosaccharides, polysaccharides, fatty acids, and glycerol do not contain the amino group and are not involved in protein synthesis.

Assigning the subjects to groups at random is important in order to ensure scientifically valid results because it helps to eliminate bias and ensure that the groups are comparable. Random assignment helps to ensure that any differences observed between the two groups are due to the medication and not other factors. It helps to control for confounding variables and increases the internal validity of the study.

In dark conditions, Chlorella is unable to perform photosynthesis due to the absence of light. As a result, it relies on cellular respiration for energy production. During cellular respiration, organic compounds, including glucose, are broken down to release energy. This process requires the uptake of oxygen and the release of carbon dioxide, leading to a negative uptake (release) of CO2. Therefore, the correct answer is that cellular respiration is taking place.

Glucose is the correct answer because it undergoes hydrolysis in a process called glycolysis, which occurs in the cytoplasm of cells. During glycolysis, glucose is broken down into pyruvate, and this process releases energy in the form of ATP. The ATP generated from glycolysis is then used as a source of energy for muscle contraction. Therefore, the hydrolysis of glucose provides the necessary energy for muscle contraction.

not-available-via-ai

During aerobic cellular respiration, ATP molecules form in the mitochondrial matrix and inner mitochondrial membrane only. This is because the process of aerobic respiration occurs in the mitochondria, where the majority of ATP synthesis takes place. The mitochondrial matrix is the innermost compartment of the mitochondria, where the citric acid cycle occurs, leading to the production of ATP. The inner mitochondrial membrane contains the electron transport chain, which generates a proton gradient that drives the synthesis of ATP through the process of oxidative phosphorylation. Therefore, ATP molecules do not form in the cytoplasm or the outer mitochondrial membrane during aerobic cellular respiration.

Methylation of some regions of DNA prevents transcription by adding a methyl group to the DNA molecule, which can inhibit the binding of transcription factors and RNA polymerase to the DNA. This prevents the transcription of genes in those regions, leading to a decrease in the production of specific proteins. This regulation of gene expression allows cells to specialize by selectively activating or deactivating certain genes, enabling different cell types to develop with unique functions and characteristics.

When the pH in a stomach increases from 2 to 4, it means that the stomach becomes less acidic. The pH scale is logarithmic, which means that each unit change in pH represents a tenfold change in acidity or alkalinity. Therefore, an increase in pH from 2 to 4 indicates a decrease in hydrogen ion concentration by a factor of 100.

During glycolysis, glucose is broken down into two molecules of pyruvate. Pyruvate is then further processed in the aerobic pathway of cellular respiration, specifically in the Krebs cycle. NADH is also produced during glycolysis as a result of the oxidation of glucose. Both pyruvate and NADH are essential for the subsequent steps of cellular respiration, making them necessary products of glycolysis. The other options, NADPH and ATP, are not directly produced during glycolysis but have other roles in cellular processes.