Answer:
Nerve impulse
Explanation:
A nerve impulse is transmitted through the synaptic cleft by acetylcholine. When an impulse reaches the synaptic knob, it stimulates the vesicles to move towards the presynaptic membrane releasing the acetylcholine. The transmitter substance makes the membrane permeable. An action potential is then formed along the neuron.
Answer:
A physical change, such as a state change or dissolving, does not create a new substance, but a chemical change does. In a chemical reaction, the atoms and molecules that interact with each other are called reactants. In a chemical reaction, the atoms and molecules produced by the reaction are called products.
Explanation:
Answer: For an animal or being to move from one place to another.
Explanation:
Birds migrate from north to south every year. (Example)
Endocasts of Homo erectus (left) and Homo sapiens (right) illustrate rapid increase in brain size. As early humans faced new environmental challenges and evolved bigger bodies, they evolved larger and more complex brains. Large, complex brains can process and store a lot of information.