Correct Answer: B

Rationale: The correct answer is B: Ureter. The ureter is the muscular tube that carries urine from the kidneys to the bladder. The nephron is the functional unit of the kidney responsible for filtering blood and producing urine. The urethra is the tube that carries urine from the bladder out of the body. The glomerulus is a network of capillaries in the nephron where filtration of blood occurs.

Correct Answer: A

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.

Correct Answer: A

Rationale: The main function of the kidneys is to filter waste products, excess ions, and water from the bloodstream to form urine, which is then excreted from the body. This process helps maintain the body's internal environment by regulating the balance of electrolytes, fluid volume, and pH levels. While the kidneys do produce urine as a result of filtering the blood, their primary function is to filter waste products rather than solely producing urine. Although the kidneys play a role in regulating blood pressure by controlling blood volume and electrolyte concentration, their main function is waste filtration. While the kidneys do produce hormones like erythropoietin and renin that regulate physiological processes, such as red blood cell production and blood pressure, the main role of the kidneys is waste filtration.

Correct Answer: C

Rationale: The correct answer is C, Cardiac muscle. Cardiac muscle fits the description provided in the question as it exhibits involuntary contractions, striations, and is predominantly located in the heart. Skeletal muscle, while also striated, is voluntary and not involuntary like cardiac muscle. Smooth muscle lacks striations and is typically found in the walls of internal organs. Elastic muscle is not a recognized type of muscle tissue in human anatomy, making it an incorrect choice.

Correct Answer: B

Rationale: Kidney failure is the term used to describe the inability of the kidneys to effectively filter waste products from the blood. Dehydration refers to insufficient fluid intake and not the kidney's filtering function. Incontinence is the loss of bladder control, not related to kidney filtration. Nephritis is the inflammation of the kidneys, not specifically related to the kidneys' inability to filter waste products.