Chemical reactions convert to . In nonliving systems, the presence of a(n) allows the reaction to proceed very quickly and have a lower . In living systems, this function is carried out by proteins called . activation energy
catalyst
enzymes
products
reactants

According to piaget, children have acquired the cognitive skill of conservation when they're able to a. understand that six ounces of liquid in a jar and six ounces in an elongated tube are equal. b. understand the viewpoint of other people. c. relate objects around them to their own needs. d. realize that the term heavy describes an object one way and the term big describes it another way. it is not b nor c. did this 2 x wrong..

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

Support mangrove trees out of the water. a) pneumatophores b) prop roots c) sand dunes d) tide supports