Q1. 1. Every time Spike went to a boxing match, he wanted to see a knockout. Finally his friend explained what happens when someone gets knocked out. What is the explanation? What may be the repercussions?

2. Explain how hypothalamus of the brain and the autonomic nervous system allow us to fight or flee in a stressful situation.

3. What are the differences between myelinated and unmyelinated axons? Which conducts axon potentials (nerve impulses) more rapidly? Why give reasons?

Q2. In the tide pool, a student encounters an organism with a hard outer covering that contains much calcium carbonate, an open circulatory system, and gills. The organism may well potentially be a crab, a shrimp, a barnacle, or a bivalve. The presence of which structures would allow for the most certain identification of the organism?