Correct Answer: A

Rationale: The endocrine system is largely responsible for controlling stress through the release of hormones such as cortisol and adrenaline. These hormones help regulate the body's response to stress by increasing heart rate, blood pressure, and energy production. The endocrine system plays a crucial role in the body's stress response and helps the body adapt to and cope with stressful situations. The digestive system (Choice B) is primarily responsible for breaking down food and absorbing nutrients, not controlling stress. The lymphatic system (Choice C) is responsible for immune function and maintaining fluid balance, not controlling stress. The respiratory system (Choice D) is responsible for the exchange of oxygen and carbon dioxide, not controlling stress.

Correct Answer: A

Rationale: Thiamine is another name for Vitamin B1. It is an essential vitamin that plays a crucial role in energy metabolism and is important for the proper functioning of the nervous system. Vitamin B2 is riboflavin, not thiamine. Vitamin B6 is pyridoxine, not thiamine. Vitamin D is a different vitamin responsible for calcium absorption and bone health, not thiamine. Therefore, the correct answer is Vitamin B1.

Correct Answer: C

Rationale: The correct answer is C: Columnar Epithelium. Columnar epithelium is characterized by tall, pillar-like cells that are closely packed together. This arrangement allows for absorption and secretion in tissues like the digestive tract, where this type of epithelium is commonly found. Squamous epithelium (choice A) consists of flat cells, cuboidal epithelium (choice B) has cube-shaped cells, and transitional epithelium (choice D) is found in areas that need to stretch and expand, like the urinary bladder.

Correct Answer: B

Rationale: The correct answer is B: The pulmonary artery carries blood from the heart to the lungs. The first step in pulmonary circulation involves the right ventricle of the heart pumping deoxygenated blood into the pulmonary artery. The pulmonary artery then carries this deoxygenated blood from the heart to the lungs for oxygenation. This step is crucial for the exchange of carbon dioxide for oxygen to occur in the lungs, facilitating the oxygenation of blood. Choices A, C, and D are incorrect because they do not represent the initial step in pulmonary circulation. Option A refers to blood moving away from the heart, option C describes the gas exchange process that occurs in the lungs but not as the first step, and option D mentions oxygenated blood moving through the aorta, which happens after oxygenation in the lungs.

Correct Answer: C

Rationale: The skeletal system collaborates with the nervous system by providing protection and support for critical nervous system components. The vertebrae of the spine play a crucial role in safeguarding the spinal cord, a key component of the nervous system responsible for transmitting messages between the brain and the body. Protecting the spinal cord is essential to prevent neurological complications. Choices A, B, and D are incorrect because while bones do play a role in body position and can sense pain, the primary focus of the skeletal system's interaction with the nervous system is to protect vital components like the spinal cord, rather than generating nerve cells.