Practice TEAS Science Test

Correct Answer: B

Rationale: The correct answer is B: Medulla oblongata. This part of the brain is located in the brainstem and is responsible for regulating essential involuntary functions such as breathing, heart rate, and blood pressure. It contains vital centers that control these functions, making it the correct choice. Rationale: 1. Cerebrum (A): The cerebrum is responsible for higher brain functions such as thinking, memory, and voluntary movements. It does not directly control involuntary functions like breathing and heart rate. 2. Cerebellum (C): The cerebellum is involved in coordination, balance, and muscle movement but does not regulate involuntary functions like breathing and heart rate. 3. Thalamus (D): The thalamus acts as a relay center for sensory information but is not primarily involved in controlling involuntary functions like breathing and heart rate. In summary, the Medulla oblongata is the correct answer because it specifically houses the centers that control vital involuntary functions, distinguishing

Correct Answer: B

Rationale: The correct answer is B: To filter waste from the blood. The kidneys play a crucial role in filtering waste products, excess substances, and toxins from the blood to form urine. This process helps maintain the body's overall balance of fluids and electrolytes. Choices A, C, and D are incorrect as the kidneys do not produce digestive enzymes (A), white blood cells (C), or red blood cells (D). The primary function of the kidneys is to regulate fluid and electrolyte balance, remove waste products, and help control blood pressure.

Correct Answer: C

Rationale: Natural Killer Cells produce Perforin to create pores in the target cell membrane, leading to target cell rupture. Perforin forms channels in the cell membrane, allowing for the entry of granzymes that induce apoptosis in the target cell. Interferon is produced by infected cells to inhibit viral replication. Apoptosis is a programmed cell death process. Antibodies are produced by B cells in response to antigens but are not involved in the direct lysis of target cells by Natural Killer Cells.

Correct Answer: B

Rationale: The primary function of white blood cells is to fight infection. They are key components of the immune system, identifying and attacking pathogens like bacteria and viruses. White blood cells produce antibodies to neutralize invaders. This function helps the body defend against illnesses and maintain overall health. Choices A, C, and D are incorrect because carrying oxygen (A) is primarily done by red blood cells, transporting nutrients (C) is mainly performed by blood plasma, and transporting waste (D) is mainly the role of the kidneys and liver.

Correct Answer: B

Rationale: The correct answer is B because the pericardium is actually a double-walled sac around the heart, not a single-walled layer. The outer layer is the fibrous pericardium, and the inner layer is the serous pericardium. Choice A is correct because the pericardial fluid between the layers reduces friction. Choice C is also correct because the pericardium helps prevent overfilling of the heart. Choice D is correct as well, as the pericardium does protect and anchor the heart. Therefore, the only incorrect statement is B, as the pericardium is not a single-walled layer.