1. What is the role of surfactant in the respiratory system?

A. To trap dust particles
B. To increase lung compliance
C. To produce mucus
D. To generate oxygen during respiration

Correct answer: B

Rationale: The correct answer is B: 'To increase lung compliance.' Surfactant is a substance produced by the alveolar cells in the lungs that reduces surface tension within the alveoli. This helps to prevent the alveoli from collapsing, making it easier for the lungs to expand and contract during breathing. This action increases lung compliance, which is the ease with which the lungs can be inflated. Trapping dust particles (A) is the role of mucus and cilia in the respiratory system. Surfactant does not produce mucus (C) but rather acts to reduce surface tension. Generating oxygen (D) is the function of the respiratory system as a whole through the process of respiration, and surfactant does not play a direct role in this process.

2. What is the difference between a homozygous recessive genotype and a homozygous dominant genotype?

A. Both have the same phenotype, but different genotypes.
B. Both have the same genotype, but different phenotypes.
C. Homozygous recessive has two dominant alleles, while homozygous dominant has two recessive alleles.
D. Homozygous recessive has two identical recessive alleles, while homozygous dominant has two identical dominant alleles.

Correct answer: D

Rationale: Rationale: - Homozygous recessive genotype refers to an individual having two identical recessive alleles for a particular gene (e.g., rr for a trait where r represents the recessive allele). - Homozygous dominant genotype refers to an individual having two identical dominant alleles for a particular gene (e.g., RR for a trait where R represents the dominant allele). - The difference between the two genotypes lies in the specific alleles present in each case, with homozygous recessive having two recessive alleles and homozygous dominant having two dominant alleles. - This genetic difference results in different phenotypes being expressed, as the dominant allele typically masks the expression of the recessive allele in heterozygous individuals.

3. What is the main function of peroxisomes in the cell?

A. To break down hydrogen peroxide
B. To synthesize lipids and other cellular components
C. To package and transport proteins
D. To store genetic material

Correct answer: A

Rationale: Rationale: Peroxisomes are membrane-bound organelles found in eukaryotic cells that contain enzymes involved in various metabolic processes. One of the main functions of peroxisomes is to break down hydrogen peroxide, a toxic byproduct of metabolism, into water and oxygen through the action of the enzyme catalase. This process helps protect the cell from oxidative damage caused by hydrogen peroxide. While peroxisomes are involved in other metabolic functions such as lipid metabolism and the synthesis of bile acids, their primary role is the breakdown of hydrogen peroxide.

4. The author most likely included information about the Silk Road to...

A. Introduce a famous tourist destination.
B. Explain the architectural style of Petra.
C. Emphasize the historical context of the city.
D. Compare Petra to other ancient trade centers.

Correct answer: C

Rationale: The Silk Road directly impacts Petra's history and prosperity, making it relevant to the historical context

5. Which of the following substances is an example of an acidic gas?

A. Nitrogen (NÃ¢â€šâ€š)
B. Carbon dioxide (COÃ¢â€šâ€š)
C. Sulfur dioxide (SOÃ¢â€šâ€š)
D. Oxygen (OÃ¢â€šâ€š)

Correct answer: C

Rationale: Sulfur dioxide is an acidic gas. The other choices are either neutral or basic gases.

6. What is the main purpose of biological classification?

A. To create a rigid and unchanging system for labeling organisms
B. To understand the diversity and interconnectedness of life
C. To simplify nature into neat and tidy categories
D. To assign organisms to specific ecological niches

Correct answer: B

Rationale: Rationale: Biological classification, also known as taxonomy, is the science of categorizing and organizing living organisms based on shared characteristics. The main purpose of biological classification is not to create a rigid and unchanging system (option A) or to simplify nature into neat and tidy categories (option C). Instead, it aims to help us understand the diversity of life on Earth and how different organisms are related to each other. By classifying organisms into groups based on their evolutionary relationships, we can gain insights into the interconnectedness of life and better appreciate the complexity and beauty of the natural world. Assigning organisms to specific ecological niches (option D) is more related to ecological studies rather than biological classification.