1. During gas exchange in the alveoli, what happens to oxygen?

A. Oxygen is released from the bloodstream into the alveoli.
B. Oxygen is absorbed from the alveoli into the bloodstream.
C. Oxygen is converted into carbon dioxide.
D. Oxygen is stored in the alveoli for later use.

Correct answer: B

Rationale: During gas exchange in the alveoli, oxygen is absorbed from the alveoli into the bloodstream. In the alveoli, oxygen diffuses across the thin walls of the alveoli and into the surrounding capillaries where it binds to hemoglobin in red blood cells. This oxygen-rich blood is then transported to the body's tissues for cellular respiration. Therefore, option B is correct as it accurately describes the direction of oxygen movement during the process of gas exchange in the lungs.

2. What is the function of the pituitary gland?

A. Produces hormones that regulate growth and metabolism
B. Filters blood and removes waste products
C. Stores and releases bile
D. Produces red blood cells

Correct answer: A

Rationale: The pituitary gland is often referred to as the "master gland" because it controls the activity of many other endocrine glands in the body. It is located at the base of the brain and produces a variety of hormones that regulate various bodily functions, including growth, metabolism, reproduction, and blood pressure.

3. Which sentence avoids a dangling modifier?

A. Walking down the street, a bird swooped down from a tree.
B. Having finished the report, it was time for lunch.
C. Reading the book, I learned a lot about ancient history.
D. Exhausted from the hike, the tent was a welcome sight.

Correct answer: C

Rationale: Option C places the participle phrase "Reading the book" in front of the subject "I," eliminating the dangling modifier.

4. What is the difference between exhalation (expiration) and inhalation (inspiration)?

A. Exhalation involves active muscle contraction, while inhalation is passive.
B. Inhalation brings in oxygen-rich air, while exhalation releases oxygen-depleted air.
C. Exhalation occurs through the nose only, while inhalation can occur through the nose or mouth.
D. Inhalation warms and humidifies air, while exhalation cools and dries air.

Correct answer: B

Rationale: Option B is the correct answer because inhalation is the process of breathing in, where the diaphragm and intercostal muscles contract to expand the chest cavity, allowing air to enter the lungs. This air is rich in oxygen, which is essential for cellular respiration. On the other hand, exhalation is the process of breathing out, where the diaphragm and intercostal muscles relax, causing the chest cavity to decrease in size and air to be expelled from the lungs. This air is depleted of oxygen as it has been used up during cellular respiration. Understanding the difference between inhaling oxygen-rich air and exhaling oxygen-depleted air is crucial for comprehending the respiratory system's function and the exchange of gases in the body.

5. When you push a book across a table, the book experiences an equal and opposite force from the table. Why doesn't the table move as well?

A. The table is much heavier than the book.
B. The force on the book acts in a different direction.
C. The table has a much larger surface area, distributing the force over a wider area
D. All of the above

Correct answer: C

Rationale: While Newton's third law states that for every action, there is an equal and opposite reaction, the unbalanced force acting on each object depends on their respective masses. The larger mass of the table (compared to the book) experiences a smaller acceleration, making its movement almost imperceptible.

6. What protein complex controls the progression of mitosis through its activation and degradation?

A. Ribosome
B. Cyclin-dependent kinase (CDK)
C. Centriole
D. Microtubule

Correct answer: B

Rationale: Rationale: A) Ribosome: Ribosomes are cellular organelles responsible for protein synthesis and are not directly involved in controlling the progression of mitosis. B) Cyclin-dependent kinase (CDK): CDKs are a family of protein kinases that regulate the cell cycle, including the progression of mitosis. CDK activity is controlled by cyclins, which bind to CDKs to activate them at specific points in the cell cycle. The activation and degradation of cyclins regulate the activity of CDKs, which in turn control the progression of mitosis. C) Centriole: Centrioles are involved in organizing the microtubules of the mitotic spindle but do not directly control the progression of mitosis. D) Microtubule: Microtubules are structural components of the cytoskeleton and are involved in various cellular processes, including mitosis, but they do not control