Heart Lab

This blog is to sum up the ECG lab. In this lab we measured our heartbeats. We were able to do this by hooking up electrodes to our arms and then connected by wires the electrical currents were able to be picked up. We measured several people and it was crazy to see how different all of them were. Jodi's was the highest of all of the graphs and I am not exactly sure why this was. Her R wave was definatly had the highest peak a long with the S wave having the highest dip. Then we also measured me and Nicks and ours were much different. Our heartbeats were very straight and did not have such extreme peaks and dips in the QRS complex unlike Jodi's. This could be because we were more relaxed or that it was low because we were in basketball and were in good condition. Whatever the case this blog showed the close up of these wiggly lines called the QRS complex.

At the finale of this lab we also got to play around with blood pressure while using interesting instruments. We used several different types of readers such as the normal velcrow and pump ones that are found in most doctors offices or the newer ones that are put around the wrist and automatically take the reading. From the lab I learned that is typical for women to have a slighty lower blood pressure for whatever reason that may be.

Nervous System

Pain,pleasure,being tickled is all apart of the wonderous nervous system. Laced through out the body the networks of cells communicate to stimulate muscles or glands to do various tasks. The nervous system is made mostly up of neural tissue but also has blood vessels and connective tissue. There are two different cells type: nerve cells and neuroglial cells. The Nerve cells are made to react to physical and or chemical changes to their surroundings. The communication of the cells is all started when the the small cells called dendrites receive the input and theen a longer process called a nerve fiber or axon carries the information away from the cell in the form of nerve impulses. When all the axons are bundled up this is what you call a nerve. Almost a coating over the Axon is what is called Myelin sheath which is a higher proportion lipid that contains a cytoplasm
Another important part of the nervous system are the small spaces between the neuron and the cell,which is called a synapse. Most of the job the nerouvs system has is to send and recieve messages between neurons and the other cells at the synapse. The conveyor belt of this whole nervous system is what you would call neurotransmitters. There are also organs in the nervous system that are split into two groups. One of the groups is called the central nervous system and it is made up of the brain and the spinal cord. THe other groups is called the peripheral nervous system and it is composed of nervous and is connected to the central nervous system. Sensory receptors gather information by detecting changes though out the body and also on the outside of it. They detect and monitor things like light,sound,remperature and oxygen concentration.Sensory receptors convert the information they recieve and then transmitt or send the information to the central nervous system. When they reach the CNS they come together to create sensations that help to produce thoughts.There are also motor functions of the nervous system and they are carried out by impulse carrying neurons that head to the central nervous system to help muscles contract in response to stimulation.

The diagram above shows the shape of the cell in simple form. As you can see the neuron is made up of dendrites on the edge that are almost tentacle like. Also you can see the axon that carries information to the axon endings. Lastly you see the myelin sheath that wraps around the axons almost like a bandage.

The next activity we did was we were assigned partners and had to put together a project on the nervous system. In our group we chose to go over how marijuana and alcohol effects the brain. From this assignment I learned many things including the part of the brain that is most effected by drugs and alcohol and how the brain is effected. I also learned about the short and long term effects of the two of those substances on the brain. Here is the link for the presentation that we did as a group.

Heart Anatomy

The heart is a major factor in circulating blood throughout the body and keep the body alive. The heart pumps around 7,000 liters though the body a day. Thats a huge amount for such a small organ. Around the heart there are vessels and viens that help with blood circulation, this system is called the cardiovascular system. There are two different circuits called the pulmonary and the systemic circuit. The pulmonary circuit is when the oxygen depleted blood is sent to the lungs to pick up oxygen and drop off carbon dioxide. The other circuit is called the systemic circuit and it is when oxygenated blood and nutrients are sent throughout the body cells and helps to remove wastes. The inside of the heart is divided into four chambers. The top chambers, the left and right atrium, have think walls that recieve blood returning to the heart. The lower chambers are the left and right ventricles and they force blood into the arteries.There are two septums in the heart called the interatrial septum and the interventrical septum. The interatrial septum seperates the left and right atrium and the interventricular septum seperates the two ventricles. The left and right atriums communicate to each other by a opening called the atrioventricular orifice and it is guarded by the av valve.
The right atrium recieves blood from two large veins called the superior,and inferior vena cava. The blood these veins return is low oxygen and from the tissues. As the blood travels through the heart it goes to the pulmonary trunk which is the only place for it to exit. While in the trunk it divides into either the left or right pulmonary arteries that eventually lead to the lungs. At the bottom of the trunk is the pulmonary valve. When the right ventricle contracts the valve opens and blood runs through. The left atrium receives the blood from for four pulmonary veins. Two are in each lung.

In class we had a lab when we disected a pig heart and viewed the different arteries and how they transported blood throughout the heart. From the lab I learned that the heart is a lot larger than I thought and is also much more complex than I gave it credit for. Down below are pictures of the disected pig heart.

Leach Lab Blog

During this lab we dissected a leach to test and observe the nervous system. The equipment for this lab were: Feather,Probe,Forceps,Scissors,Pins,Scalpel,Dissection Tray,Leech Tank,20% Ethanol Leech Tongs, Dissection Microscope,Micromanipulator,Oscilloscope, and finally of course the leech.
Step 1

Catch and anesthetize the leech in 20% ethanol solution. Ethanol is not an anesthetic for vertebrate animals, but can be an effective anesthesia for small creatures that breathe through the skin like the leech. Like in many things, too high a concentration will be harmful or fatal.
Step 2

Pin the animal dorsal side up through the anterior and posterior suckers onto a dissection tray, stretching the animal in the process.
Step 3

Using scissors, make a cut in the skin along the mid-line on the dorsal surface, taking care not to damage deep structures.

Using forceps, carefully tease apart the skin along the cut and pin down the left and right halves of the skin to each side, so that the leech is pinned open with the inside of the skin facing up. This exposes the innards of the leech, including the digestive, excretory and reproductive organs. You cannot see the nervous system yet, because they are located ventrally.
Step 4

Carefully remove the gut and other internal structures to expose the ventrally located nerve cord. The nervous system of the leech is encased within the ventral sinus, which is dark green in color.
Step 5

Notice that there are many swellings up and down the sinus. These contain the segmental ganglia of the nervous system. To make one of them accessible, first we cut a window in the body wall underneath a ganglion, taking care not to damage the nerve cord or any attached nerves in the process.

Step 6

Isolate a section of the animal by making 2 parallel cuts across the animal (perpendicular to the anterior-posterior axis), but sufficently separated so that the strip you remove contains at least one ganglion.

Then, with forceps, flip the piece of skin over so that the outer skin is now face up. Pin the skin down. If you don't know why you are doing this, go read the Why are we doing this? of Step 5 and come back.
Step 7

Cut the sinus with an ultra fine scalpel and using fine forceps, carefully tease apart the sinus to expose the ganglion. Individual cells can now be viewed under the microscope.

In reality, you would only use the scalpel here only if you are extremely good at microdissection. It's very difficult to cut just the sinus without accidentally damaging the ganglion underneath, but hey, we are all perfect in cyberland. Normally, this is done with a pair of very fine forceps.
Now you've come to the crux of the matter. All the preparation so far has been to make this step possible. You might want to review Nervous System background or Electrical Equipment background at this point.

Click on the electrode to gain control of it. Move the electrode to somewhere over the ganglion then click on the mouse button. This simulates the process of penetrating the cell, which is much more demanding in reality (see "What it's like in reality." for details). Keep your eyes glued to the oscilloscope display while you are doing this. If you find a cell, the display will change. If you see no change, then you have not found a cell. Keep moving your electrode around and clicking until you find a cell. The sound you hear is the oscilloscope display you are seeing fed into an audio amplifier. It provides an audio feedback to what you see on the screen.

Now using a feather, probe or forceps, push around the skin of the animal. Observe if the cell you have penetrated responds to weak (feather), medium (probe), strong (forceps) or any stimulus. Note the pattern of response. The cell may fire action potentials or spikes. The response characteristics will be used when you are comparing your data with published data compiled in the atlas.

When you are satisfied with the electrophysiology, you can start the anatomical investigation by injecting the cell with a fluorescent dye. Push the button labeled "Dye Injection.
Step 9

Next, we will visualize the morphology of the neuron from which you have just recorded using a fluorescent dye. Having pushed the button labeled "Dye Injection," the amplifier system has passed an electric current from the electrode that resulted in the ejection of Lucifer Yellow from the tip of the electrode into the intracellular space. Lucifer Yellow will passively spread throughout the cell after a while. Now you can turn on ultraviolet (UV) light by pushing "UV Switch.". Lucifer Yellow fluoresces bright yellow-green under UV and you will be able to visualize the cell in question, including its axon, dendrites, cell body and so on.

Step 10

You now have electrophysiological data and neuroanatomical data from your experiment. Try to identify the cell based on published data (Atlas) There are many cells in different locations of this ganglion. Repeat the whole procedure for as many cells as you would like.
I showed the steps above just to show the exact steps I went through to complete the lab and see how the nervous system properly works. In this lab after taking all of the insides of the leech we found the central nervous system of the leech. Then we cut parts of the nervous system into pieces and tested them to see what kind of cells they are. At the end of the lab when you dye the cells and probe them to see what kind of cell in the nervous system you are testing. Certain cells did not stimulate when poked by the feather while others one were very stimulated by it. This Lab showed me how the different cells come together to form the nervous system. Also after doing this lab I got to see a new type of technology with the Oscilloscope. I have never even heard of the Oscilloscope but after using this lab I got to see what it can do. After taking the nervous system apart piece by piece I was able to see how amazing and mind blowing the nervous system is when it is all put together and functioning properly. Even though this lab was rather simple I believe I learned a lot about the nervous system.

Research Blog:Spare Parts for Humans: Tissue Engineers Aim for Lab-Grown Limbs, Lungs and More

In this article I learned of the amazing things scientists can make our bodies do. At the start of the video it shows a marine named Mile O'Brien who has most of the skin and some of the muscle in his leg destroyed. His muscle is literally visible on his leg. However working with the these amazing tissue engineers they are working on ways to be able to grow tissue or even organs to repair damaged human bodies. Using stem cells and a lot of rigorous physical therapy they found that they were able to turn the cells into muscle. With the help of the scientists Mr. O'Brien was able to regenerate around 10 to 15 percent of the muscle he lost. However, the muscle has gotten so strong that it is the same as him regenerating 50% of the muscle. They might even be able to make extra body parts for people being able buy.They have been working on over 30 different tissues and organs and even extra appendages like ears and even a beating heart valve. Most of these experiments have been testing on salamanders and seen on the movie they actually regenerate limbs. There was also another example of a man that dove into the shallow end of a pool and was completely paralyzed. With the help of stem cells though he was able to talk move his arms and getting stronger. He is believing that he will be able to walk again at the rate he is going. I had no idea that it was possible to repair the body this much. Its awesome that we have this technology to give people there lives back that were injured. After watching this video I am amazed at the things that we are able to do with science
http://www.freerepublic.com/focus/f-news/2822704/post

Sliding Filament Model

We already made a short video of this process but I would like to also post a blog on here to show my individual understanding of the process as well. This is mostly about the contraction and relaxation of the muscles and what goes on inside the body. Inside the muscle fibers are the sarcomeres and they help with contraction of the muscles in the skeleton. When the muscle contracts the sarcomeres do not change length like you would thnk, instead they simply slide past each other. In our video it is shown as the two forks and the match box. Instead of the fork pokers(I do not know the correct term for them)bending into the match box,them simply slide past them fitting in almost perfect fashion.The fork pokers do slighty overlaap each other but they do not change in length by any means. As the muscle relaxes the forks or sarcomeres are pulled away from the match box and are slid back to their resting spot. Working almost like a machine the muscle is able to smoothly flex and relax.

This is a different example than the one we used in our video but it is explaining the same thing. As you can see instead of the sarcomere(fingers) changing length the simply just slide through each other and stay the same length. Going back to the start of this blog i didnt go all the way through the process of the sliding filament model because it can be explained in the video I helped create. Hopefully this blog does somewhat show my knowledge of the Sliding Filament Model

Skeletal System

Called the framework of the body the Skeletal System is what supports and holds up the the body. The bones can be split into two different catagories: Axial Skeleton and Appendicular Skeleton. The Axial Skeleton is the bones of the skull the vertebral column also know as the spine and the rib cage. The Appendicular Skeleton is the bones of the upper and lower limbs the shoulders, and hips. The bones can also be classified by the different shapes they can be in. The first type is the long bones. These bones are longer than wide and example of these bones would be the Humerus or Femur. The opposite of the long bones would of course be the short bones. These bones are cube shaped and are on the wrist and ankle. These bones usually from within the tendons for example the patella and the trapezoid. Flat bones are of course thin and flattened and a bit curved for example the sternum and most skull bones. The last type of bone is Irregular Bones and these bones live up to their name by being oddly shapped like the vertebrae and hip bones.
Function of Bones
Bones have many important functions to making sure the body is up and running. Bones are the support of the body and are the framework of the body and support the soft organs. They also help to protect the brain, spinal cord, and vital organs. They also help for movement of the body and provide levers for the muscles. The bones also are a storage systom for minerals, mostly for calcium and phosphorus. The last function of the bones is the formation of the blood cells.
Bone Fractures
Bone fractures are classified by the position of the bone ends after the break, the completeness of the break, orentation of the bone on the long axis, and whether or not the bone penetrates the skin.There are multiple types of bone fractures. Nondisplaced fractures are when the bone retains its normal position. A complete break is when the bone is broken all the way through. Mostly common in sports, a spiral break is when the bone is excessively twisted. The most common injury among children is the greestick fracture and it occurs when one side of the bone breaks and the other side bends.

This picture shows a complete break,and as you can see the fracture has taken place throughout the entire bone.

This picture shows an greenstick fracture. As you can see the one side of the bone breaks as the other side bends.