👉 Biological fluids, also known as body fluids, are essential components of the human body that perform a variety of critical functions. These fluids include blood, lymph, saliva, mucus, and synovial fluid, among others, each with specific roles. Blood, for instance, transports oxygen, nutrients, hormones, and waste products throughout the body, while also playing a key role in immune defense and clotting. Lymph serves a similar circulatory function but primarily aids in immune response by carrying white blood cells and filtering out pathogens. Saliva lubricates the mouth, aids in digestion, and contains enzymes that start breaking down food. Mucus lines the respiratory, digestive, and reproductive tracts, trapping harmful particles and pathogens to prevent their entry into sensitive areas. Synovial fluid lubricates joints, reducing friction and absorbing shock during movement. Collectively, these fluids maintain homeostasis, support cellular function, and protect the body from damage.