UIL Science Review 4/24

Which of the following best describes the role of mitochondria in cell biology?

• They are the site of protein synthesis.

• They package and distribute proteins.

• They are involved in the digestion of cellular waste.

• They are the powerhouse of the cell, providing energy through the process of cellular respiration.

Answer explanation

The mitochondria are the powerhouse of the cell, providing energy through the process of cellular respiration.

In a chemical reaction, what does the principle of conservation of mass state?

• The total mass of the reactants increases after a chemical reaction.

• The total mass of the reactants decreases after a chemical reaction.

• The total mass of the reactants equals the total mass of the products.

• The total mass of the products is always zero.

Answer explanation

The principle of conservation of mass states that the total mass of the reactants equals the total mass of the products in a chemical reaction.

Which of the following is a key principle of Mendelian genetics?

• Traits are inherited as discrete units called genes.

• Organisms inherit two copies of each gene, one from each parent.

• Both A and B are correct.

• None of the above.

Answer explanation

The key principle of Mendelian genetics is that traits are inherited as discrete units called genes and organisms inherit two copies of each gene, one from each parent. Therefore, both statements A and B are correct.

Which of the following best describes the concept of ecological succession?

• The process by which a community acquires its final, unchanging form.

• The predictable replacement of one community by another over time.

• The random formation of new species within a community.

• The decrease in species diversity within a community.

Answer explanation

Ecological succession is the predictable replacement of one community by another over time, as different species establish and thrive in an area.

Which of the following laws explains why it is harder to stop a moving truck than a moving bicycle?

• Newton's First Law of Motion

• Newton's Second Law of Motion

• Newton's Third Law of Motion

• The Law of Conservation of Energy

Answer explanation

Newton's Second Law of Motion states that the force needed to stop an object is directly proportional to its mass and acceleration. A truck has more mass than a bicycle, so more force is required to stop it.

What principle does Pascal's law relate to?

• The behavior of gases under pressure

• The transmission of fluid pressure in all directions within a fluid

• The increase of pressure at a point in a fluid at rest due to the weight of the fluid above it

• The buoyant force on an object submerged in a fluid is equal to the weight of the fluid displaced by the object

Answer explanation

Pascal's law relates to the transmission of fluid pressure in all directions within a fluid.

Which of the following best explains the function of ribosomes in a cell?

• They are the site of lipid synthesis.

• They are responsible for detoxifying drugs and poisons.

• They are involved in the modification, sorting, and packaging of proteins and lipids.

• They are the site of protein synthesis.

Answer explanation

Ribosomes are the site of protein synthesis in a cell, where they translate mRNA into proteins. This is their primary function.

What does the law of segregation in genetics state?

• Each individual has two alleles for each gene, which segregate during gamete formation.

• Genes for different traits are sorted independently of one another in the formation of gametes.

• Alleles for a trait are distributed to offspring based on probability.

• Genetic traits are inherited based on environmental factors.

Answer explanation

The law of segregation in genetics states that each individual has two alleles for each gene, which segregate during gamete formation. This means that the alleles separate and only one allele is passed on to each offspring.

What is the primary function of chloroplasts in plant cells?

• They are responsible for breaking down sugar molecules to release energy.

• They are involved in the storage of genetic material.

• They play a key role in the process of photosynthesis, converting light energy into chemical energy.

• They assist in the production of proteins within the cell.

Answer explanation

Chloroplasts play a key role in photosynthesis, converting light energy into chemical energy, making them essential for plant cell survival.

According to Darwin's theory of natural selection, which of the following statements is true?

• Individuals adapt to their environment during their lifetime and pass these adaptations to their offspring.

• Species that are stronger and more intelligent are guaranteed to survive and reproduce.

• Organisms with traits that increase their chance of survival and reproduction are more likely to pass on these traits to the next generation.

• All members of a species evolve together at the same rate.

Answer explanation

Darwin's theory of natural selection states that organisms with traits increasing survival and reproduction are more likely to pass on these traits to the next generation.