1. The lymphatic system is primarily responsible for:

A. Transporting nutrients throughout the body
B. Removing excess fluids and waste products from tissues
C. Producing red blood cells
D. Regulating body temperature

Correct answer: B

Rationale: The correct answer is B: 'Removing excess fluids and waste products from tissues.' The lymphatic system plays a crucial role in maintaining fluid balance in the body by collecting excess interstitial fluid and returning it to the bloodstream. This system also helps in removing waste products, pathogens, and toxins from tissues, contributing to the body's immune response. Options A, C, and D are incorrect because transporting nutrients, producing red blood cells, and regulating body temperature are primarily the functions of other systems in the body such as the circulatory system, bone marrow, and the thermoregulatory system, respectively.

2. The "fight-or-flight" response is triggered by the hormone released from the:

A. Thyroid gland
B. Adrenal glands
C. Pituitary gland
D. Pancreas

Correct answer: B

Rationale: The correct answer is B: Adrenal glands. The "fight-or-flight" response is a physiological reaction that occurs in response to a perceived threat or danger. When this response is triggered, the adrenal glands release adrenaline, also known as epinephrine, into the bloodstream. This hormone prepares the body for action by increasing heart rate, dilating airways, and redirecting blood flow to essential organs. The thyroid gland (option A) primarily regulates metabolism, the pituitary gland (option C) controls many other hormone glands, and the pancreas (option D) is responsible for regulating blood sugar levels through the production of insulin and glucagon, but they are not directly involved in the fight-or-flight response.

3. What is the difference between heat and temperature?

A. They are the same thing.
B. Heat is a form of energy, while temperature measures the average kinetic energy of particles.
C. Heat flows from cold to hot, while temperature flows from hot to cold.
D. Heat is measured in Celsius, while temperature is measured in Joules.

Correct answer: B

Rationale: Heat is a form of energy transfer, while temperature reflects the average kinetic energy of particles within a substance.

4. In the reaction 4Al + 3O2 â†’ 2Al2O3, what is the mole ratio of aluminum to oxygen?

A. 4:3
B. 2:3
C. 3:2
D. 3:4

Correct answer: a

Rationale: The coefficients in the balanced equation represent the mole ratio, which is 4 moles of Al to 3 moles of O2.

5. The body's first line of defense against pathogens is the innate immune system. Which of the following is NOT a component of the innate immune system?

A. Physical barriers like skin and mucous membranes
B. Phagocytes that engulf and destroy pathogens
C. Inflammatory response to isolate and contain infection
D. Production of antibodies specific to a particular pathogen

Correct answer: D

Rationale: The innate immune system is the body's first line of defense against pathogens and includes physical barriers like skin and mucous membranes, phagocytes that engulf and destroy pathogens, and the inflammatory response to isolate and contain infection. However, the production of antibodies specific to a particular pathogen is a function of the adaptive immune system, not the innate immune system. The innate immune system provides immediate, nonspecific defenses, while the adaptive immune system generates specific responses to target pathogens. Therefore, option D is NOT a component of the innate immune system, making it the correct answer in this question.

6. What are enzymes?

A. Building blocks of muscle
B. Biological catalysts
C. Energy source
D. Antibodies

Correct answer: B

Rationale: Enzymes are proteins that speed up chemical reactions in our cells. They act like tiny factories, fitting specific molecules (substrates) into their active site to facilitate reactions.