The brain and spinal cord are part of the nervous system.
The electrical charges that act as nervous signals are called .
Jellyfish do not have a brain. Instead their nervous system is called a .
After nervous systems began to develop in bilaterally symmetric animals, some developed ventral, or front, nerve cords, while chordates developed nerve cords.
Skeletons that allow for movement by using muscles and squeezing liquid to change the body shape are called skeletons.
do not grow with arthropods, and so occasionally must be shed and regrown from chitin.
Muscles move endo- and exoskeletons by .
is the joining of two gametes called sperm and egg.
A fish that lays her eggs in a cluster is initiating fertilization.
are an adaptation by reptiles to allow for reproduction and embryo development on land.
Describe three different strategies used by three different animals to thermoregulate.
If you see a snake coiled up in a sunny patch of grass, what can you probably conclude about the type of thermoregulator it is. Why?

1. central

2.  action potential

3.  nerve net

4.  dorsal

5.  hydrostatic

6.  Exoskeletons

7.  contraction/contracting

8.  Fertilization

9.  external fertilization

10.  Eggs

11.  Animals with fur thermoregulate by panting. Winged birds will flap against their mouths/heads to dissipate heat. Humans will produce sweat to evaporatively cool. Polar bears have developed blubber. Bears drop body temperatures during hibernation.

12.  Seeing a snake using the warmth of the sun leads us to conclude that it is likely a thermo conformer that cannot produce its own body heat.

Explanation:penn-Foster

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.

answer; microsoft;