*emergency* ! true or false? 13. all synaptic transmission is electrical rather than chemical. 14. acetycholine, discovered by otto loewi was one of the first neurotransmitter chemicals identified and is released from nerve endings to decrease heart rate. 15. when you send a message from your skin that you've touched something hot, a motor neuron sends the message to the brain.

How do water’s relative densities as a solid and a liquid differ from that of most other substances? water’s solid and liquid forms have different densities, while most other substances have solid and liquid forms with similar densities. water’s solid and liquid forms have similar densities, while most other substances have solid and liquid forms with different densities. water’s liquid form is less dense than its solid form, while the opposite is true of most other substances. water’s solid form is less dense than its liquid form, while the opposite is true of most other substances.