Human brain contains trillion vein. The human brain has the same general structure as the brain of this mammals but is larger than any other in relation to body size. Th brain is the most complex organ is the human body and perhaps the most remarkable. This jelly-like mass of tissue, weighing in at around1.4 kilograms, contains a staggering one hundred billion nerve cells or neurons.
The human cerebral cortex is a thick lager of neural tissue that covers most of the brain. This layer is folded in a way that increases the amount of surface than can fit into the volume available. The pattern of folds is similar across individuals, although there are many small variations. The cortex is divided into four"lobes" called the frontal lobe,parietal lobe,temporal lobe, and occipital lobe.
The left and right sides of the cortex are broadly similar in shape and most cortical areas are replicated on both sides. Some areas though show strong lateralization,particularly areas that are involved in language in most people the left hemisphere is "dominant" for language, with the right hemisphere playing only minor role.
There are many divided in vein such as internal jugular vein,cerebral veins, external veins, basal vein,terminal vein,choroid vein, cerebellar veins.
Scientifically, the techniques that are used to study the human brain differ in important ways from those that are used to study other animal species. On the one hand, invasive techniques such as inserting electrodes into the brain, or disabling parts of the brain in order to examine the effect on behavior, can be used with non-human species, but for ethical reasons, are generally not performed with humans. On the other hand, humans are the only subjects who can respond to complex verbal instructions. Thus, it is often possible to use non-invasive techniques such as functional neuroimaging or EEG recording more productively with humans than with non-humans. Furthermore, some of the most important topics, such as language, can hardly be studied at all except in humans. In many cases, human and non-human studies form essential complements to each other. Individual brain cells can only be studied in non-humans; complex cognitive tasks can only be studied in humans. Combining the two sources of information to yield a complete functional understanding of the human brain is an ongoing challenge for neuroscience.
Overall brain is more useful for human body. If we have no brain, imagined it, we can't do anything