Biomes include both biotic and abiotic elements. Which set includes both biotic and abiotic elements of an estuary? A. cordgrass water salinity, great blue herons
B. ospreys, oysters, black needle rush
C. silt, air temperature, tidal pattern
D. periwinkles, bats, egrets

Abird flies by moving its wings up and down. which two systems are most directly responsible for the movement of a bird's wings? a. skeletal and muscular systems b. respiratory and muscular systems c. skeletal and digestive systems d. respiratory and digestive systems