Unit 6 Reflection

This unit was all about the brain and its behavior. In this we learned about the brain and the many different structures and the functions of them as well. The brain is composed of the forebrain, midbrain, and hind brain. It is also has many other parts. The cerebrum is located in the area where the forebrain is. It is sectioned into a right hemisphere, which controls the left side of the body and overall picture, and the left hemisphere, which controls the right side of the body and language and detail. It is also sectioned into different lobes: frontal, temporal, occipital, and parietal. The frontal lobe is in charge of executive control. The temporal lobe is in charge of language, hearing, and memory. The occipital lobe is in charge of vision. The parietal lobe is in charge of sensation. The cerebellum, which is located in the back of the brain, controls motor control and motor memory. The pituitary gland is located right below the hypothalamus, which maintains homeostasis, and is in charge of sending off hormones. In our sheep brain dissection, we were able to physically view many of the structures in the brain. More explanations of the different structures and functions can be found there. We also learned how the brain can adapt as we grow older through brain plasticity. In one of our first readings titled "Women of 24 found to have no Cerebellum in her Brain," explained how the body can adapt to problems such as this. It displays how one part of the brain does not do one function; all the different structures work together in unison to allow a person to perform day-to-day activities. Also, the reading "A Woman Perpetually Falling," discussed a women that had problems with her vestibular apparatus. It described how she was able to find a doctor who found a way around this by taking advantage of the brain's plasticity. An article called "How to Come a Superager," explained how exercise prevents the brain from deteriorating as fast.

We also learned about our senses and the difference between sensation, which is the receiving of input from the environment via sensory neurons, and perception, which is the brain interpreting and organizing sensory info. There are four main senses: sight, hear, taste, and smell. In sight, the main organ is the eye, and it uses photoreceptors. We were able to physically examine the path that light travels through the eye with the sheep eye dissection. We learned that in a myopic person, which is known as nearsightedness, an individual's eye is too long, causing the image to land in front of the retina. In a hyperopic, or farsighted, person, their eyes are too short, causing the image to land behind the retina. In hearing, the main organ is the ear, which has mechanoreceptors. The ear can hear by the auditory ossicles magnifying sound which amplifies to the cochlea, which contains the tiny hair cells that physically process the sound waves. The organ for smelling is the nose, which has chemoreceptors. Sensory cells in the nose are located higher up, allowing the chemicals that enter the nose to travel there. Taste is very similar to smell. It uses the organ of the mouth, which also uses chemoreceptors, to sense taste. Taste buds on the tongue take in tastants, which dissolve in saliva to enter one of the five specialized receptors. The reading "Fit Body, Fit Brain and Other Fitness Trends," showed that exercise greatly decreases the deterioration of brain function and young fit people tended to have better brains as they grew older. Also, it prevented chromosomes from deteriorating.

The article "How we get Addicted" explained how addiction is a real and serious disease that many people fight. It talked about how people struggle to get clean and the reasons that they get addicted in the first place. This related to the next chapter of the unit, which was neurons and some of the nervous system. A neuron is composed of a cell body, axon, which conducts nerve impulses away from the cell body; axon terminals, which pass the signal from the dendrites; dendrites, which receive impulses and move them to the cell body; and a synaptic cleft that separates axons from each other. The signal gets moved along through action potentials, which is basically the rapid changing of charge along the axon, with sodium ions coming in and potassium ions going out, allowing the signal to be passed on. When it reaches the synaptic cleft, it releases neurotransmitters that pass through the synapse, sending the signal on to the next neuron. The nervous system is made up of the central nervous system, which acts as the command center, and the peripheral nervous system, which serves as the communication lines. In these nervous systems, there are many different diseases that can form. One example of a central nervous system disease is meningitis, which is the inflammation of the meninges, which usually creates a blood-brain barrier for the brain. An example of a peripheral nervous system disease is shingles, where the body develops painful and itchy rashes on the skin. We discussed how addiction is in fact a disease because there are signs and symptoms and many risk factors. Addiction can cause some change in the brain that include brain structure, brain pathways, and brain chemicals. The four C's of the addiction cycle are craving, compulsion, loss of control, and continued use despite consequences.

I think that some of my bigger strengths are the nervous system because I have already learned about it in biology. Even though it is not a topic that I did particularly well on, I still have learned it earlier, making the relearning process much easier. One of my weaknesses is the different diseases and structures of the brain. Even though we worked on the brain for a good amount of time, it is still difficult for me to grasp some of the locations of the parts. Also the diseases in general are hard to learn in such a short period of time. I want to learn more about specific aspects about the brain such as seizures. I want to know more about what exactly causes them to happen besides the fact of an overload of information. Why does extreme exhaustion affect them? What distinguishes a dangerous seizure from a harmful one? I also want to go more into the topic of concussions since it is a very prominent topic in sports and around people that I know in general. I don't think that I have been doing that well on my New Years Goals physical wise. I have not been able to find the willpower or time to go out and run on my own. I have still been exercising though. However, I think I've done a good job relating what we learn to my own life. I know many people who had brain issues and I was able to think about my own eyes and how the light would travel through them.