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Thursday, March 16, 2017

Unit 6 Reflection

This unit focused on our brain and how it connects our bodies. It controls all of our movements, basic functions and is able to comprehend sensory input and react with the appropriate action. Our brains are made up of nervous tissues (neurons) that work together to create a complex system of communication. It takes information in from the ears, eyes, nose, mouth and skin to allow us to hear, see, smell, taste and feel.

In order to get a better understanding as to how the brain and eyes work, we dissected a brain and eye of a sheep. We were able to see how all of the parts are connected; the most memorable for me was the brain lab, because I could clearly see the division of left and right brain connected by the corpus collosum.

"The Woman with a hole in her Brain" by Helen Thomson is about a girl in China who had lived without a central sulcus until age 24. The central sulcus separates the frontal and parietal lobes of the brain, and without out it, her sensory skills are impaired, which is why she did not learn how to walk until age 6 and talk at age 7.

"How to Become a Superager" by Lisa Feldman Barrett explains how older people who are mentally nimble tend to be more active, physically. They have purpose in their lives and work, no matter the intensity of the tasks. They learn to overcome pain in a healthy and productive way, rather than relying on medications as they age. This is because plasticity allows our brains to adapt and grow overtime, and learn new information.

"Fit Body, Fit Brain and Other Fitness Trends", by Gretchen Reynolds explains the importance of physical activity. In specific, she mentions that the telomeres, or caps at the ends of our chromosomes, shrink with age. However, those who maintain a healthy lifestyle have proven to have longer, and stronger telomeres.

"How We Get Addicted" by Michael D. Lemonick is an article that medically describes addiction as a disease. Although many believe that it is only a psychological problem, it is in fact a physical disease that we cannot just wish away. Sensory adaptation desensitizes our sensory cells overtime, and overwhelming amounts of dopamine can do the same.

Finally, "A Woman Perpetually Falling", is a book following a woman who was born without a vestibular system, vital for our sense of balance. She was not able to stand on her own because her body did not provide the sensations necessary for understanding balance. However, overtime, her brain learned to overcome this deficiency, another example of brain plasticity.

I found this unit incredibly interesting because we are learning about our brains while using our brains and experiencing these different processes. I think it is a very in depth topic that I overanalyze and confuse myself with, but for the most part I understand the concepts. Our brain has four different lobes that control different parts. The frontal lobe is the boss of executive functioning, the parietal controls muscle movement, the temporal lobe controls auditory functions, and the occipital lobe is in charge of sight. The brain is divided laterally into left and right parts that are connected by the corpus collosum.

My new years goals have been going well now that I have put more energy into achieving them. I have already reached a 200 pound squat and want to continue focusing on form before increasing more weight. I also have been getting much more sleep which is very important for my overall wellbeing. I have to force myself to put my phone down but once I do, I sleep well.

Wednesday, March 15, 2017

Reflexes Lab

1. In this lab, we learned that our bodies have certain reflexes as a mechanism to protect our bodies. For example, our irises contract in the sunlight to shield us from the extra harsh light. The sensory information travels down a synapse to the brain and then responds quickly. In order to test these, we did several experiments.
2. a) The photo pupillary reflex contracts the smooth muscle of the iris to control the size of the pupil. Upon shining a phone light at my partner's eye, her pupils did contract and become smaller. This is because we need to be able to constantly adapt to our environments, and by adjusting how much light is let into our eyes, we are better able to stay alert.
b) The patellar reflex causes the knee to jerk in a monosynaptic reflex. It occurs so fast because there is only one synapse in the circuit needed to complete the reflex. This proved to be true when the knee of my partner immediately kicked out when tapping the spot of the knee. This is a good defense reflex to have evolved because at one point we would be able to quickly react to danger
c) The blink reflex is a defense barrier we create to protect ourselves. By throwing a cotton ball towards my partner's eyes, I am simulating possible danger causing her to blink without thinking.
d) The plantar's reflex is used to measure the strength of the body's communication lines. In some diseases such as MS, the signals to the brain are interrupted and therefore the reflex irregular.
e) The reaction tests for this part doesn't measure a single reflex, but your ability as a whole to respond to stimuli.

3. Texting made a much more delayed reaction time, because your brain is trying to balance focus between the ruler and composing sentences.

Brain Dissection Relate and Review

In this lab, we dissected sheep brains in order to have a better understanding of the brains structures and functions. I observed a clear distinction between the two hemispheres of the brain by the corpus collosum which transfers information between the two.
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3. Myelin is an insulation for neurons that speeds up processing and transmitting signals and allows for faster communication.
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6.

   

Strength Comes Slow: 20 Time Progress Report #2

So far, my 20 time project has been slow but steady. Learning to hold a solid and controlled handstand does not come with instant results, it takes patience and practice. I am goal oriented and so this project has been frustrating at times, because I cannot have a clear-cut, number defined goal. I've been taking time lapse videos of my progress so far, and I have slowly noticed that my balance has increased. Doing exercises such as squats and core activation drills helps to improve strength.




I have also added on to my project. I want to see how other people's balance is better/worse depending on their life styles. I will survey a large group of people by timing their ability to stand on one foot with and without their eyes closed, and then compare it to the sports they play.

Since starting this 20 time project, I have been sick several times which stops me from being able to go to the gym and workout everyday. Although this sets me back, it is also important to take care of my body. I will continue to practice these drills and also find new ones that will help condition muscles from all angles.

In unit 6, we have learned a lot about the vestibular system, which ties in a lot with my project. I find it very interesting that our bodies can improve balance and even make up for disorders that occur.


Monday, March 6, 2017

Sheep Eye Dissection Analysis

 In this lab, we used sheep eyes to develop a deeper understanding of the structure of an eye. We examined the eye from an external view as well as internally once dissected.

Sclera, white tissue
We know that the sclera, or the whites of the eye is tough and fibrous to protect the cornea and internal eye, and so in order to view the internal anatomy we must cut through it.
Optic nerve  
Similar to the sclera, the cornea also serves as protection, controls the entry of light and is the outermost lens of the eye
We noticed the optic nerve that projects from the back of the eye; it transmits signals to the brain through ganglionic (nerve) cells

Once making a frontal cut into the eye, we are able to see the two hemispheres revealing the retina, vitreous humor and choroid.


To the left we can see the retina peeling away from the choroid to reveal the tapetum lucidum, which reflects light onto the retina so that animals can see better in low lights. Humans do not have this, which explains why animals have better night vision.
The vitreous humor maintains the shape of the eye and once scraping it away the lens was revealed. The pupil lies inside the iris and is a small opening that regulates the amount of light that enters the eye.

Eyes contain sensory cells called rods and cones. These help to see shades of grey and different colors.
When light enters the eye it follows a pathway that leads it to the optic nerve. It enters the cornea, which focuses our vision. It goes through the gelatinous aqueous humor which gives the eye structure. Entering the iris, the pupil controls how much light goes through depending on the surroundings, (kind of like aperture on a camera). It travels through the vitreous humor which separates the retina from the pupil which contains the rods and cones. Finally, the optic nerve sends this information to the brain for processing.