Final answer:
Neutrophils and macrophages form pseudopodia, which are temporary cytoplasmic extensions that facilitate cell motility and are crucial for the phagocytosis process in our immune system.
Step-by-step explanation:
Neutrophils and macrophages extend cytoplasm into the extracellular matrix, forming pseudopodia. These are temporary extensions of the cytoplasmic membrane produced through the forward flow of soluble actin filaments, leading to the creation of cell motility. This process is central to the function of phagocytes in our immune system, which engulf and digest foreign particles via phagocytosis. Pseudopodia are distinct from other cellular structures such as cilia and flagella, which are made of microtubules and aid in locomotion, and microvilli, which are involved in absorption.