(1) People can do math problems by learning, and dogs can also do this simple calculation. This is a new behavior gradually established through life experience and "learning" after birth, which belongs to learning behavior.

(2) Pupils can calculate 2+3=5, which is a unique human conditioned reflex when pupils understand the meaning of numbers through the language center; Dogs can calculate 2+3=5, which is caused by certain conditions such as the shape of numbers (the gesture of animal trainers or the color of plates, etc.). ), but the puppy doesn't understand its meaning, and it belongs to a conditioned reflex caused by a specific stimulus involving the cerebral cortex.

(3) The brain consists of two hemispheres. The surface of the cerebral hemisphere is gray matter, called cerebral cortex. The more important centers in the cerebral cortex are: body movement center (which manages the movement of contralateral skeletal muscle), body sensation center (which is related to the stimulation of contralateral skin and muscle, making people feel), language center (which is related to speaking, writing, reading and understanding language, and is a unique nerve center for human beings), and visual center.

So the answer is: (1) learning;

(2) significance; Shape;

(3)B