Which work against each other to maintain homeostasis?
A. Hormones and neurotransmitters
B. Motor neurons and sensory neurons
C. Somatic and autonomic nervous systems
D. Sympathetic and parasympathetic nervous systems

Organisms are classified, or grouped into categories, based on similarities in their characteristics and/or evolutionary relationships. the study of how organisms are classified is known as

Put the following steps of the convection process in the correct order. 1. gravity pulls cooler matter downward. 2. the matter expands and decreases in density. 3. an up-and-down flow of matter produces a convection current. 4. matter is heated. 5. warmed matter is forced upward. question 2 options: a) 4, 2, 5, 1, 3 b) 2, 4, 3, 1, 5 c) 3, 2, 5, 4, 1 d) 1, 4, 2, 5, 3

Cells destroy body cells infected by a virus or bacteria.