I'm not sure about the first two but I think the one about the halite crystal is cubic. :)
I think tissue or a nucleus
<span>These are viroids. They are some of the smallest types of matter that have been shown to take on the properties of living beings. They have the ability to replicate, while not having many of the mechanisms that are commonly found in DNA and required for them to replicate.</span>
Velocity is how fast the river is moving, the Volume is how much is in the river!
Tissue damage activates nociceptors or pain receptors in the skin. A signal is sent to the peripheral nerve to the spinal cord where neurotransmitters or chemical messengers are released. It activates other nerves to pass signal to the brain. The signals are relayed to the somatosensory cortex for sensation, frontal cortex for thinking and limbic system for emotional response.