Unit 5 Reflection

This unit we began by covering the digestive system. The digestive system provides us with nutrients through the breaking down of food. Many of the organs in the digestive tract act as a long tube that keeps the contents away from our body cells. In the String lab, we discussed the length of all the alimentary canal organs stretched out. Other organs, called accessory organs, bring digestive juices to break down the contents to nutrients. The Whole process starts in the mouth with chewing and salivation. Then I swallow and the bolus goes down my esophagus to my stomach. My stomach churns and acid and enzymes eat away at the chyme.

In horses only part of their stomach is glandular, the part that secretes gastric juices. 

After a couple hours, the chyme enters duodenum, then travels to the jejunum and finally the ileum. In the small intestine, the pancreas and liver release enzymes that break down the food and help the small intestine absorb the nutrients as it travels through it. Finally, the remaining matter enters the large intestine where water is removed and is excreted through the anus. Relating to this metabolism is how our body uses the nutrients we take from the digestion process. For the most part, people in Saratoga remain in the fed state most often. The sugars we absorb are taken to the liver and made into glycogen. The remaining nutrients go to body cells(insulin is high and they are ready to take in glucose); the amino acids go to the liver, but the other nutrients become adipose tissue. Then we enter the fasting state. Once again this is quite common in Saratoga, as it occurs in the hours following eating. As the insulin levels drop the glucagon levels rise and glucogenesis, the making of glucose from amino acids and glycerol, kicks in. The body begins to rely on fat for energy and breaks down some adipose tissue, giving the heart and muscles energy. Ketone bodies begin to be made at this point. Finally, the body reaches the starvation state within the next week. Adipose tissue supplies the muscles, while the brain is fueled by ketosis and the glucose is used for making RBC. Eventually, only the vital organs will remain barely functional at which point death shortly follows.
Unfortunately, this metabolic process goes wrong at times often resulting diabetes. In type 1 diabetes the body attacks the beta cells on the pancreas, preventing insulin from being released.Without insulin, the Gult-4 receptors cannot take in glucose to use. In type 2 diabetes the body no longer responds to the insulin and can no longer take in glucose either. Both result in thick syrupy blood that can result in clots and high blood sugar. Long term the kidneys can become problemed from the hyperglycemia and eventually fail.

Diabetes has risen to epidemics in the US. 

The endocrine system controls the hormones in our body. Hormones are chemicals that our body releases to signal other parts of the body to trigger responses. A steroid hormone is lipid based hormone that can travel through cell membranes. The steroid goes into the nucleus and binds with the DNA. Nonsteroid hormones cannot go through the cell membrane so they use receptors on the cell's outer surface. Insulin is one of these that need to react with the receptors to activate a response. In diabetes this is what goes wrong and does not respond. The nonsteroid hormones reacting with the receptors causes a domino effect in the cell. The endocrine system uses negative feedback to regulate the amount of hormones in the body. This works like a thermostat where when it gets to the desired temperature (or hormone level in this case) the supplier shuts off. One major gland is the pituitary gland. This can directly react with the body or it can trigger other glands to release their hormones.

The lymphatic system is like the sewer system of our body. It cleans up the fluids that have come out of the circulatory system and cleans up after the inflammatory response. This system runs closely with the circulatory system, wherever there is a capillary there are lymph capillaries that help clean up. They also are intertwined in each villi to catch anything leaking out of the gut. The lymphatic system has a central pump, but it mainly relies on muscles and valves to pump the lymph around. The lymphatic system produces WBC for the body's immune system. Whenever we go to the doctor they always poke around in our neck area. That is because we have many lymph nodes there. If we are sick with a cold they will be soft and swollen because the lymph system is catching and collecting clumps of the bacteria in the lymph nodes. In cancer the lymph nodes will be hard. The tonsils catch anything that enters through the mouth. The thymus helps develop T-cells.  The spleen makes and recycles RBC.
My goals I have begun to work towards. I wrote my relate and reviews promptly except for one. This has helped me be less stressed about class and more prepared. My running I have not started. I am going to keep this goal. In order to push myself more and give me an incentive, I have signed up for a 4-mile race in April. Now I feel like I have a purpose to run.