The brain is the most sophisticated organfound within most species. Its ability to receive, interpret, and directsensory information of any kind truly makes it marvelous. Composed of the spinalcord and the brain, the nervous system is the most essential system in thebodies of most mammals. “Although the brain constitutes only 2% of the totalbody weight, its metabolic demands are extremely high. It utilizes around 20 %of the total oxygen and 20 % of the total glucose consumption” (Fblt.cz, 2018).
The most prominent feature of the brain, the cerebrum, is divided into twohemispheres (right and left) as shown in Figure.1that accounts for nearly 85% of the total brain mass (Windward.hawaii.edu,2018). Such a significant part of the brain is responsible for carrying outhigher thought process which include language, learning, memory, and much more(Icuf.org, 2018).
As shown in Figure.1,the cerebrum is completely engulfed with folds of tissue known as gyri. Groovesfound outlining the gyri are known as sulci and together they both increase thesurface area of the cerebrum allowing for more neurons which can be used forvarious purposes in the brain (Bailey, 2018). Likewise, a fissure serves thesame role as a sulcus, however it is relatively deeper in depth and is used todivide the four lobes; parietal lobe, frontal lobe, occipital lobe, and the temporallobe as seen in the cerebral cortex in Figure.2. This part of the brain consists ofnearly 90% of all the neurons found in the brain which suggests that most ofthe transmission of neural signalling occurs here via synaptic transmission (Human-memory.net,2018). Located at the front-most end of the cerebral cortex, the frontal lobeis responsible for the decision-making process, problem solving, and all theexecutive actions made by the body.
Similarly, the parietal lobe is associatedwith recognizing various sensory information meanwhile the occipital lobe is responsiblefor distinguishing various colors and what one sees. However, the temporallobe’s main function is to perceive auditory information and is involved withmemory, speech, and emotions (ThoughtCo, 2018). As you move along the cerebrumand proceed to go down, the cerebellum is seen (smaller version of a cerebrum)as shown in Figure.1. The joint thatconnects between the cerebrum and the cerebellum is known as the transversefissure, and once cut, separates the two regions as shown in Figure.3. The cerebellum’s job is to regulatemuscle movement and maintain constant balance within the body (Anon, 2018). When comparing the gyriof the cerebellum and the cerebrum, one can easily tell that there are muchmore gyri found in the cerebrum and that the gyri present in the cerebellum isnot as big as suggested by Figure.
4. Whenthe brain is flipped and placed on its ventral side, the two prominent features,the olfactory bulb and the optic chiasma can be shown in Figure.5. In most mammals, the olfactory bulbs are used to processvarious smells present in an environment (Encyclopedia Britannica, 2018).Unlike the olfactory bulbs which are used to process smell, the optic chiasma isthe location where the optic nerves cross; transmit image from your eyes to thebrain (Verywell, 2018). As you move along the brain and come near the spinalcord, you come through the midbrain, pons, and medulla oblangata which are all partof the brain stem as shown in Figure.
6.The medulla serves as a gateway connection between the spinal cord and thecerebellum and maintains involuntary actions such as breathing, digesting, etc.Likewise, the pons connects the medulla with the cerebellum followed with themidbrain (Windward.hawaii.edu, 2018). Interestingly, the pons and the midbrain releasethe neurotransmitters, Norepinephrine and Serotonin which are both considered stresshormones which aid in sleep, temperature, appetite and neuroendocrine control (Hajjawi,2018).