1. Which of the following is the primary function of the lymphatic system?

A. Transporting oxygen and nutrients to cells
B. Carrying waste products away from tissues
C. Regulating body temperature
D. Producing red blood cells

Correct answer: B

Rationale: The correct answer is B: 'Carrying waste products away from tissues.' The primary function of the lymphatic system is to collect excess fluid from tissues and return it to the bloodstream, while also transporting waste products, pathogens, and cellular debris away from tissues to be filtered and eliminated. This helps maintain fluid balance in the body and supports the immune system by removing harmful substances. Options A, C, and D do not accurately describe the primary function of the lymphatic system, making them incorrect choices.

2. Antigen-antibody binding is the principle behind:

A. Vaccination
B. Disinfection
C. Sterilization
D. antibiotic resistance

Correct answer: A

Rationale: Rationale: Antigen-antibody binding is the principle behind vaccination. When a vaccine containing antigens (weakened or killed pathogens) is introduced into the body, the immune system produces antibodies that bind to these antigens. This binding triggers an immune response, leading to the production of memory cells that provide immunity against future infections by the same pathogen. Vaccination helps the body develop immunity without causing the disease itself, thereby protecting individuals from infectious diseases. Disinfection and sterilization involve different processes to eliminate or reduce pathogens on surfaces or objects. Antibiotic resistance is a phenomenon where bacteria evolve to resist the effects of antibiotics and is not directly related to antigen-antibody binding.

3. When is work done by a force on an object?

A. Only when the object moves in the direction of the force
B. Only when the object moves against the force
C. Only when the object moves vertically
D. Only when the force is applied for a specific duration

Correct answer: A

Rationale: Work is done by a force on an object when the object moves in the direction of the force. If the object moves perpendicular to the force, no work is done, as the force does not contribute to the displacement of the object. Similarly, if the object moves against the force, work is done because the force is causing the displacement. The vertical movement of the object does not determine whether work is done; it is the direction of the force relative to the object's displacement that matters. The duration of the force application does not affect whether work is done; as long as the force causes the object to move in its direction, work is being done.

4. What is the main factor limiting population growth in K-strategists?

A. Predation
B. Availability of resources
C. Competition
D. Disease

Correct answer: B

Rationale: Rationale: K-strategists are species that have a low reproductive rate and invest more resources in raising fewer offspring. These species typically inhabit stable environments where resources are limited. The main factor limiting population growth in K-strategists is the availability of resources such as food, shelter, and space. When resources are scarce, K-strategists may struggle to find enough resources to support their population size, leading to decreased reproductive success and population growth. Predation (option A), competition (option C), and disease (option D) can also impact population growth, but the primary limiting factor for K-strategists is the availability of resources.

5. If 3 nurses can care for 15 patients, how many nurses are needed for 25 patients?

A. 4
B. 5
C. 6
D. 7

Correct answer: B

Rationale: 3 nurses / 15 patients = x nurses / 25 patients. Solve for x.

6. What is the 3D structure of a protein called?

A. Tertiary structure
B. Secondary structure
C. Primary structure
D. Quaternary structure

Correct answer: A

Rationale: Rationale: - Primary structure refers to the linear sequence of amino acids in a protein. - Secondary structure refers to local folded structures within a protein, such as alpha helices and beta sheets. - Tertiary structure is the overall 3D shape of a protein, which is determined by interactions between amino acid side chains and the environment. - Quaternary structure refers to the arrangement of multiple protein subunits in a protein complex. Therefore, the 3D structure of a protein is called the tertiary structure because it represents the overall folding of the protein into a specific shape.