Owl Pellet Lab Analysis

In this lab, we dissected an owl pellet and observed the bones of a mysterious organism. We first started the dissection off by weighing how much the pellet weighed, which for ours was around 5.41 grams. We then measured the pellet, which was 2.9 centimeters wide by 4.1 centimeters long. We then used a probe to pick apart the pellet, while using tweezers to hold the pellet still. The pellet mainly consisted of feathers and fur. However, we also discovered the bones of what we believed to be a vole, based on the comparisons of the bones structure to that of the owl pellet handbook.

Our first evidence to support this claim is the size of the mandible we discovered from the pellet. According to the owl pellet handbook, the size of the mandible for a vole is about 20 millimeters, or around 2 centimeters. As you can see in the photo below, the mandible we discovered is around 2 centimeters too.

Our second piece of evidence to share is the shape of the skull we discovered in the pellet too. Despite the skull not being longer than the mandible, it still had some noteworthy features with it's shape similar to the vole from the handbook. As you can see in the photo below, the teeth of the skull are more sharper and pointier. We can also observe that the eye sockets (which were thickly filled with pellet remains) are oval shaped, similar to that of the vole from the handbook. 

Our last piece of evidence to present is the humerus that we believe are part of the vole. As you can see in the photo below, we believe we found two humerus' based on the bone indentations. As you can see on both ends, the bones are round and indented at each end. In the middle of the bones are minor indentations, similar to that of the illustration in the owl pellet handbook. 

In many ways, the bones of various organisms throughout the world are similar to that of humans. In this case, voles have very similar distinctions to human skeletons along with differences in the skeletal system. One similarity between a vole skull and the human skull is the mandible, as they hinge to the skull and open up and down just like human jaws. The jaw of the vole also has teeth used to aid in digestion, similar to us humans with our incisors and canines as teeth. Another comparing similarity to draw is the upper leg of the vole is similar in shape to the humerus of the human skeleton, as they both have sockets that hinge onto along with bone indentations at each end and in the middle.

Some notable differences however is the space between the jaw and teeth, as the teeth for humans is at the very front while the teeth for vole are closer to the middle. Another comparing difference is the shape of the eye sockets, as the voles' eye socket is shaped like an oval while a human eye socket is shaped more circular. Another notable difference is the shape of the skull, as the human skull is longer than it is wide, while the vole skull is wider than it is long.

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Unit 6 Reflection

Unit 6 was centralized around the nervous system, along with it's physiology and how it communicates with the body. The main themes in this unit were how do different senses react to a certain environment and how does the body communicate with itself. We first learned about sensation vs. perception, where the brain interprets messages through perception while sensation is where we receive input from our environment. We also have different receptors that interpret our environment: thermoreceptors (temperature), Pain receptors, Photoreceptors (eyes), Chemoreceptors (chemicals), and mechanoreceptors (movement). We learned about these receptors during our reflex lab, in which we tested common reflexes in the human body. For example, our photoreceptors were used when testing our photopupilary reflex, or when our eye is exposed to light after a while in the dark. These reflexes are made possible due to neurons, which send electrical impulses through their myelin sheaths that communicate to the body what to do. One of the first readings in the chapter was the "How to Become a "Superager", in which the article talked about how vigorous mental and physical exercises can have 60+ year olds be just as smart as their 20 year old counterparts. Our second reading was the "Fit Body, Fit Brain", in which the article discussed that any type of exercise can add unused neurons to the brain and sharpens thinking skill. Exercising can also reduce their telomere reductions, preventing neurological diseases too. Our last reading was the "How to Get Addicted" reading, where the article discusses how addiction is in fact a neurological disease such as obesity, as the brain is wired to eat instead of being normal. One of the main readings in the unit was the "Women Perpetually Falling", as it talked about future cures for paralysis and diseases involving the brain and spinal cord. My main strength in the unit was knowing the difference between perception and sensation, as the two are greatly different but can sometimes be confused. My other greatest strength was knowing which type of receptors belonged to which organ or sense. However, my main weakness was the physiology of a neuron, as I am puzzled about how it can communicate messages instantly throughout the body. I would like to learn more about different reflexes in the body, since I find it appealing that these reflexes naturally occur in our body. I would also like to learn more about how the brain matures as we get older too.
As of my New Year goals, I am currently failing one, getting an A in Anatomy and Physiology. My final grade comes out to about an 87.5 percent after all tests have been submitted. The tests have been a major reason as to why my grades have been getting lower. To resolve this, I plan to study more rigorously, and rematch past vodcasts to ace the next test. However, I am succeeding in my second new year goal, getting bigger in hopes of playing college football. I have recently been given a scholarship by Puget Sound to play defensive line in exchange of taking two years of tuition debt off my record. I have also noticed people complimenting me recently, saying I have been getting bigger and more built.

That is it as of now. Check back soon for future labs and updates!

Reflex Lab

In this lab, we tested multiple reflexes in the human body and our mechanorecptors too. In order to learn about this lab, we had to study the nervous system and it's anatomy and physiology. The main component of the nervous system is the neuron, a nerve cell that transmits nerve impulses throughout the body. Neurons help make our body mobile and agile, all due to the reflexes in our body. A reflex is a response to a stimulant, and is usually not forced, but rather a natural part of the body.
When shining a light into a closed iris hidden in the dark, we are testing the photo pupillary reflex. The iris widened when exposed to light, most likely due to the iris adjusting to the sudden light change in the eye. The second experiment dealt with the patellar reflex, just below the knee cap and is usually tested during a physical. The patellar reflex did occur since it was stimulated through a gentle tap into the kneecap. The third reflex tested was our blink reflex. We as humans tend to close our eyes when being subjected to pain. We threw a cotton ball at an invisible barrier, and both times tested we did blink. This most likely occurred since we naturally as humans close our eyes when we are about to experience pain. The fourth reflex tested was the plantar reflex. We stroked a pen down the sole of our feet, and our toes did flex. This occurred due to the high amount of neurons in our foot, and how sensitive our feet are. Lastly, we measured how fast we reacted by grabbing a dropping meter stick. We tested it twice, one normally and then one while texting. We found that during texting, our reaction time increased by around 0.15 seconds. This may seem like nothing, but if we were driving, we would increase our chance of colliding with another car. This is why we have at least a two second buffer when driving behind cars, since reactions usually occur in less than a second.

Not texting

Texting

Sheep Brain Dissection

In this dissection, we examined a sheep brain and how it's functions are quite similar to that of a human brain. We first started the dissection by tearing out some meninges from the brain, a protective, shiny membrane that protects the brain. This is where the term meningitis originates from, as the disease is diagnosed when the meninges are infected or inflamed. We then cut the brain in half through the corpus callosum, a bundle of fibers that connect the two hemispheres together, to observe the left and right hemispheres. We discovered parts of the brain such as the thalamus and the midbrain, along with other main parts of the deep brain that maintain homeostasis and control our hormones. We then cut the brain again horizontally to examine the gray and white matter deep inside the brain. We have learned of white matter before, as it protects the brain from cognitive diseases such as Alzheimers, and to preserve such matter, we need to exercise daily.

A picture of the brain with pins describing each part. The white pin represents the anterior side while the black pin represents the posterior side. The red pin represents the brain stem while the green pin represents the cerebellum. Lastly, the yellow pin represents the cerebrum of the brain.

The brain dissected vertically. The lower left pin represents the optic nerve while the other white pin represents the hypothalamus. The green pin represents the medulla oblongata while the blue pin represents the pons. The black pin represents the thalamus while the red pin represents the corpus callosum. Lastly, the yellow pin represents the whole midbrain.

Observing grey and white matter. You can see grey matter at the outer ridges while white matter fills in the inner portion of the brain.

Sheep Eye Dissection Analysis

Recently, we had dissected a sheep eye to learn about it's anatomical structures along with it's functions. The first step of the dissection was removing the fatty tissue and muscle surrounding the sclera. The muscle and fat tissues served as cushions for the eye in order for it to stay in place and not pop out the socket constantly. We also noticed this hard stem-like structure sticking out the back of the eye, determining it to be the optic nerve. The optic nerve transfers visuals from the eye to the brain for the brain's interpretation, making the eye part of the sensation group. The second step of the procedure was to cut the eyeball in half through the sclera to view the inner contents of the eye. Upon opening the eye, we discovered the cornea on one side of the hemisphere and the vitreous humor on the other. The cornea is the transparent outer layer at the front of the eye, whose job is to focus the entry of light into the eye. The vitreous humor was a clear, gelatin-like substance that filled the eye to help maintain it's shape so that the eye would not be deflated. Upon closer inspection, we found the retina on the opposite hemisphere of the vitreous humor. The retina is greatly important to the eye since it sorts all neural images our eyes absorb so that they can be interpreted easily by the brain. after removing the vitreous humor from the eye, we discovered the lens. The purpose of the lens is to adjust focus according to our environment so that we can see clearly. Without the lens, our vision would be blurry and we would technically be blind. This lab helped opened my eyes (pun intended) on how little we take our eye for granted, when it provides us with the greatest natural gift of them all: vision.