The brain is the center of the nerv

The brain is the center of the nervous system in all vertebrate and most invertebrate animals. Some primitive animals such as jellyfish and starfish have a decentralized nervous system without a brain, while sponges lack any nervous system at all. In vertebrates the brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing, balance, taste, and smell.
Brains can be extremely complex. The cerebral cortex of the human brain contains roughly 15–33 billion neurons, perhaps more, depending on gender and age, linked with up to 10,000 synaptic connections each. Each cubic millimeter of cerebral cortex contains roughly one billion synapses. These neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body and target them to specific recipient cells.
The brain controls the other organ systems of the body, either by activating muscles or by causing secretion of chemicals such as hormones and neurotransmitters. This centralized control allows rapid and coordinated responses to changes in the environment. Some basic types of responsiveness are possible without a brain: even single-celled organisms may be capable of extracting information from the environment and acting in response to it. Sponges, which lack a central nervous system, are capable of coordinated body contractions and even locomotion. In vertebrates, the spinal cord by itself contains neural circuitry capable of generating reflex responses as well as simple motor patterns such as swimming or walking. However, sophisticated control of behavior on the basis of complex sensory input requires the information-integrating capabilities of a centralized brain.
Despite rapid scientific progress, much about how brains work remains a mystery. The operations of individual neurons and synapses are now understood in considerable detail, but the way they cooperate in ensembles of thousands or millions has been very difficult to decipher. Methods of observation such as EEG recording and functional brain imaging tell us that brain operations are highly organized, while single unit recording can resolve the activity of single neurons, but how individual cells give rise to complex operations is unknown.

Kết quả (Việt) 1:

Não là trung tâm của hệ thần kinh trong tất cả các động vật có xương sống và đặt không xương sống. Một số động vật nguyên thủy như sứa và con sao biển có một hệ thống thần kinh phân cấp mà không có một bộ não, trong khi bọt biển thiếu bất kỳ hệ thống thần kinh ở tất cả. Trong động vật có não nằm ở đầu, được bảo vệ bởi hộp sọ và gần gũi với các cơ quan cảm giác chính của tầm nhìn, nghe, cân bằng, hương vị và mùi.Bộ não có thể vô cùng phức tạp. Vỏ não của bộ não con người có khoảng 15-33 tỷ tế bào thần kinh, có lẽ nhiều hơn, tùy thuộc vào giới tính và tuổi tác, liên kết với lên đến 10.000 synaptic kết nối mỗi. Mỗi / mm khối vỏ não chứa khoảng một tỷ synapse. Các tế bào thần kinh liên lạc với nhau bằng phương tiện của lâu protoplasmic sợi, gọi là sợi trục thần kinh, mang xe lửa tín hiệu xung được gọi là hành động tiềm năng cho các bộ phận xa xôi của não hoặc cơ thể và nhắm mục tiêu chúng đến các tế bào người nhận cụ thể.The brain controls the other organ systems of the body, either by activating muscles or by causing secretion of chemicals such as hormones and neurotransmitters. This centralized control allows rapid and coordinated responses to changes in the environment. Some basic types of responsiveness are possible without a brain: even single-celled organisms may be capable of extracting information from the environment and acting in response to it. Sponges, which lack a central nervous system, are capable of coordinated body contractions and even locomotion. In vertebrates, the spinal cord by itself contains neural circuitry capable of generating reflex responses as well as simple motor patterns such as swimming or walking. However, sophisticated control of behavior on the basis of complex sensory input requires the information-integrating capabilities of a centralized brain.Despite rapid scientific progress, much about how brains work remains a mystery. The operations of individual neurons and synapses are now understood in considerable detail, but the way they cooperate in ensembles of thousands or millions has been very difficult to decipher. Methods of observation such as EEG recording and functional brain imaging tell us that brain operations are highly organized, while single unit recording can resolve the activity of single neurons, but how individual cells give rise to complex operations is unknown.