With which human organ systems (or human systems) are the following associated?
(i) vena cava
(ii) glomerulus
(iii) alveoli
(iv) villi
(i) Vena cava is associated with human circulatory system.
(ii) Glomerulus is associated with human excretory system.
(iii) Alveoli is associated with human respiratory system.
(iv) Villi is associated with human digestive system.