Understand the context: A nephron is the functional unit of the kidney, responsible for filtering blood and forming urine.
Identify the components of a nephron: The main parts include the glomerulus, Bowman's capsule, proximal convoluted tubule, loop of Henle, distal convoluted tubule, and collecting duct.
Analyze the options given: Alveolus, Glomerulus, Lymph node, and Bronchiole.
Recognize that the glomerulus is a key component of the nephron, where blood filtration begins.
Conclude that the glomerulus is the correct answer as it is the only option listed that is part of a nephron.