Science Challenge

Imagine Aria's body as a city. What is the function of the city's central library, akin to the nucleus in a cell?

• Control center and storage of genetic material

• Energy production

• City wall formation

• Protein synthesis

Answer explanation

The function of the nucleus in a cell is to act as the control center and storage of genetic material, which includes DNA and RNA.

In the process of baking a cake, what are the reactants?

• Ingredients present at the end of baking

• Ingredients present at the beginning of baking

• The cake itself

• Tools used in baking the cake

Answer explanation

Reactants are substances present at the beginning of a chemical reaction, which undergo a chemical change to form products.

Explain the difference between mutualism and commensalism in ecological relationships through the interaction between bees and flowers, and a barnacle living on a whale's skin.

• Mutualism benefits one species and does not affect the other

• Commensalism benefits both species involved

• Mutualism involves competition between species

• Mutualism benefits both species involved, while commensalism benefits one species and does not affect the other.

Answer explanation

Mutualism benefits both species involved, while commensalism benefits one species and does not affect the other.

In a biology class, Sophia and Benjamin are learning about flower colors. How does a dominant allele for purple flower color differ from a recessive allele for white flower color in genetics?

• Dominant allele for purple color is expressed when present in a gene pair, while recessive allele for white color is only expressed when two copies are present.

• Dominant allele for purple color is only expressed when two copies are present, while recessive allele for white color is expressed when present in a gene pair.

• Dominant allele for purple color is recessive in nature, while recessive allele for white color is dominant.

• Dominant allele for purple color is always masked by the recessive allele for white color, while recessive allele for white color is always expressed.

Answer explanation

Dominant allele is expressed when present in a gene pair, while recessive allele is only expressed when two copies are present.

Describe how energy is transferred through a food chain in a forest ecosystem.

• Energy is transferred through a food chain in a forest ecosystem by spontaneous generation.

• Energy is transferred through a food chain in a forest ecosystem as organisms consume other organisms.

• Energy is transferred through a food chain in a forest ecosystem by physical contact between organisms.

• Energy is transferred through a food chain in a forest ecosystem by photosynthesis only.

Answer explanation

Energy is transferred through a food chain as organisms consume other organisms.

During a school project on environmental science, Liam, Noah, and Abigail are discussing the impact of various human activities on climate change. Which of these activities do they identify as contributing to climate change?

• Planting trees

• Burning fossil fuels, deforestation, industrial processes, and agriculture

• Reducing waste production

• Using renewable energy sources

Answer explanation

Human activities such as burning fossil fuels, deforestation, industrial processes, and agriculture contribute to climate change by releasing greenhouse gases into the atmosphere.

Imagine Lily's body as a city. What is the role of the mitochondria in the cells of this city?

• Regulates the city's growth and division

• Stores the city's blueprint and genetic material

• Manufactures products for the city

• Produces energy (ATP) to power the city through cellular respiration

Answer explanation

The mitochondria produces energy (ATP) through cellular respiration, which is its primary role in a cell.

During a science experiment, Isla and Luna mixed vinegar and baking soda in a sealed container. What does the Law of Conservation of Mass tell us about the mass of the container and its contents before and after the reaction?

• The total mass of the container and its contents is greater after the reaction than before.

• The total mass of the container and its contents before the reaction is equal to the total mass after the reaction.

• The total mass of the container and its contents before the reaction is irrelevant to the total mass after the reaction.

• The total mass of the container and its contents is less after the reaction than before.

Answer explanation

The Law of Conservation of Mass states that in chemical reactions, the total mass of the reactants equals the total mass of the products.

Give an example of a predator-prey relationship in an ecosystem.

• Lions hunting zebras

• Eagles feeding on grass

• Wolves hunting rabbits

• Sharks eating algae

Answer explanation

The correct example of a predator-prey relationship in an ecosystem is lions hunting zebras. This relationship demonstrates the predator (lions) preying on the prey (zebras) for survival.

In a biology class, Grace and Jackson are comparing how sexual reproduction (meiosis) and asexual reproduction (mitosis) contribute to the diversity of traits in offspring. How does their comparison highlight differences in genetic variation?

• Both processes, as discussed by Grace and Jackson, involve crossing over and independent assortment to produce variation.

• According to their findings, mitosis leads to a higher degree of genetic variation than meiosis.

• They conclude that meiosis results in genetic variation through crossing over and independent assortment, while mitosis does not.

• Their comparison suggests that meiosis results in less genetic variation compared to mitosis.

Answer explanation

Meiosis results in genetic variation through crossing over and independent assortment, while mitosis does not.