Use the following diagram to answer questions 8–12:

What conditions (temperature and pH) are optimal for Enzyme B to function?

Use the following diagram to answer questions 8–12:

Which enzyme is more likely to function within the body?

Use the following diagram to answer questions 8–12:

An experiment requires that both Ezyme A and Enzyme B are used simultaneously. What conditions should be used?

Use the following diagram to answer questions 8–12:

Which enzyme works most efficiently under basic conditions?

A new drug is in its clinical trial phase. The graph below shows the data for participants sleep patterns before medication use and then after using the medication for three months. Series 1 shows the average hours slept a night for each participant prior to medication. Series 2 shows the average hours slept a night for each participant after three months of use. The average hours slept a night was obtained by recording sleep every night for one month, and then finding the average. Patients one through five took a placebo pil, not the actual Moonlight medication. Note: The y-axis is measured in hours slept a night, while the x-axis lists each anonymous patient numerically.

A separate experiment was performed that concluded patients taking Moonlight had an increase in the amount of REM cycles in a given night. Patients also reported feeling better rested. How does this experiment impact the results of the experiment described above? 

Scientists studied a species of termites and looked at their foraging habitats across the United States. The termite’s population in a given tree was measured by the level of decomposition within a tree due to the termites eating the bark. The experiment also kept track of the level of shade tolerance for each species of tree. For the species of trees in this experiment, shade tolerance fell into two main categorizes- shade tolerant (ST) and intermediate shade (IS). Lastly, they recorded the average amount of rainfall in that given month for the species location being observed. The chart below summarizes the data. Scientists hypothesized that the level of decomposition would be highest in tree species with a higher average rainfall. In addition, they hypothesized trees allowing more shade would allow for more termites, and in turn more decomposition. 

Do the results of species Acer rubrum weaken or strengthen the hypothesis? 

Genes are hereditary units that are responsible for the phenotypes of an organism. Genes are the directions for the body. Genetic change exists when genes are altered from their previous form. Genes are made up of DNA, or deoxyribonucleic acid. DNA is made up of four bases- adenine, guanine, cytosine, and thymine. Genetic change can result from a variety of factors. Both scientists mentioned below agree on this basic information about genes. However, the scientists do not agree on the primary driving force behind genetic change.

Scientist 1

A mutation is a permanent change in the sequence of the DNA of a gene. There are several types of mutations—point mutations, silent mutations, frame mutations, and nonsense mutations. Mutations are very important because proteins are synthesized by reading the DNA sequence. If the DNA sequence is changed, the proteins transcribed from the DNA will be different proteins. Mutations directly and substantially change the genes by changing the sequence of the four bases. Therefore, mutations are the main factor when looking at genetic change.

Scientist 2 

Sexual reproduction is the biggest contributor to genetic change. New combinations of genes are created with every random union of a sperm and egg. During division of the sex cells, or meiosis, crossing over can occur. Crossing over describes the situation when the genes from one parent’s chromosome are traded with genes from the other parent’s chromosome. This results in new combinations of genes. Lastly, a phenomenon called independent assortment results from sexual reproduction. Independent assortment is the random assortment of chromosomes during reproduction. Therefore, by its random nature, sexual reproduction is the largest contributor to genetic change.

When Scientist 1 states that mutations "change the genes by changing the sequence of the four bases," the word "bases" is referring to what? 

Mitochondria make 90% of the energy needed by the body to sustain life. The Mitochondrial Free Radical Theory of Aging (MFRTA) theorizes that individuals who live longest produce fewer mitochondrial oxygen reactive species than individuals that have a shorter life span. Therefore, lifespan will increase if fewer mtROS are produced, and lifespan will decrease if more mtROS are produced. An experiment was done to test this theory, and the results are shown in the chart below. Four test groups of flies were involved, two groups consisted of females, and two groups consisted of males.

An independent experiment concluded that mtROS amount had a less significant effect in male test groups than in female test groups. Assuming these results were accurate and test group 1 was a male test group, which other test group is also a male test group?

The significant increase in atmospheric carbon dioxide since pre-industrial levels can be seen in the world’s oceans which absorb the CO₂ and in turn undergo changes in chemistry. The consequences of increased CO₂ include acidification of seawater and a decrease in carbonate ion (CO₃^2-) concentration. 

Changes in seawater chemistry affect marine organisms. The early life stages of invertebrates, such as squid, may be particularly vulnerable to changes in carbon dioxide levels. Acting as both predator and prey, squid are a significant component of marine ecosystems.   For example, fish and sea birds, such as tuna and albatross, are dependent on squid as a source of prey. Furthermore, the fishing industry is impacted by the health of squid populations. California fisheries produce the majority of market squid.

In order to determine how increased levels of carbon dioxide affect the development of squid, eggs were hatched in two different conditions: normal (380 µatm) and elevated (2100 µatm) levels of CO₂. The time to hatch and the size of the larval mantle (the anatomical feature that includes the body wall and fins) were measured and recorded. Two trials were conducted for each carbon dioxide concentration.

According to the passage, which of these are most directly  affected by changes in marine carbon dioxide levels?

The significant increase in atmospheric carbon dioxide since pre-industrial levels can be seen in the world’s oceans which absorb the CO₂ and in turn undergo changes in chemistry. The consequences of increased CO₂ include acidification of seawater and a decrease in carbonate ion (CO₃^2-) concentration. 

Changes in seawater chemistry affect marine organisms. The early life stages of invertebrates, such as squid, may be particularly vulnerable to changes in carbon dioxide levels. Acting as both predator and prey, squid are a significant component of marine ecosystems.   For example, fish and sea birds, such as tuna and albatross, are dependent on squid as a source of prey. Furthermore, the fishing industry is impacted by the health of squid populations. California fisheries produce the majority of market squid.

In order to determine how increased levels of carbon dioxide affect the development of squid, eggs were hatched in two different conditions: normal (380 µatm) and elevated (2100 µatm) levels of CO₂. The time to hatch and the size of the larval mantle (the anatomical feature that includes the body wall and fins) were measured and recorded. Two trials were conducted for each carbon dioxide concentration.

In this experiment, which of the following most likely affects squid-egg hatching?