Neuromuscular junction

The neuromuscular junction is the site where an axon and a muscle fiber meet.  Nic, Brianna, Katy, Gena and myself, created this video to demonstrate the function of the junction, haha that rhymed!  To be perfectly honest it's not my favorite project, I feel we fell a little short on what we had in mind.  We had several ideas at the beginning of the project but not all of them translated very well to film.  We ended up with a simple drawing film.  Unfortunately, our editing program also fell a little flat and not everything we wanted, effects wise, was able to be produced.  However, I think our group is now quite able to tell you exactly what the neuromuscular junction is and what it looks like.  Here's a link to our work.  

http://www.youtube.com/watch?v=Spj60iQ_qjc&feature=youtu.be

I would also like to give props to Nic Libby for being so persistant with youtube!  Couldn't have done it without him!

Vertebrae Site

My mother recently came across a rather interesting site a few weeks ago that had been sent to her by a friend.  The site mainly goes into depth about the chiropractic side of things, but I found it rather interesting how each of the vertebrae in our spine effects a certain part of our body.  This may mean organs, or just certain areas.  This makes sense then, why, massage therapy, acupuncture, and chiropractic sessions can effect our movement and mood so much.  These alternative medicines, as they're classified, are really quite important to keeping our bodies happy, and healthy.  According to this site, effecting a certain vertebrae, could help with problems occurring in other places of the body.  The chart is helpful in guiding you through and matching your aches and pains to certain vertebrae in the spine.  It was convenient that my mum came across it just as we were exploring and memorizing the skeletal system.  It's really quite interesting, take a look!  http://www.chiroone.net/why_chiropractic/index.html

Chewin' chewin' all day long chewin' chewin' chewin'

The lab we performed in class was quite tasty...or interesting, interesting yes.  We tested the amount of energy/power it takes the jaw to consume a variety of foods.  We did this by attaching several sensory cords or electrode tabs to our very cooperative test subject, Seth.  These cords ran to a probe of sorts that was connected to our lap top that recorded the energy being used.  Before we began testing we created a hypothesis.  Our hypothesis stated that we believed it would take more jaw power to chew harder foods than it would softer foods.  After we made our prediction we began the test.  Our test subject started with a softer food, a banana.  The computer recorded the results.  He then consumed a carrot, celery, gatorade, a marshmallow, and finally a pop tart.  After collecting the data we concluded that our hypothesis was actually incorrect.  The graph below shows that foods like the banana actually generated more energy when being eaten.  I personally find this rather strange that the softer the food the more energy created.  

Skeletal System

(not anatomically correct)

      Bones, obviously, are the body's framework and support system.  They provide a "case" for the organs of the body, allow movement with muscles, store essential minerals, and allow blood cell formation. Though bones are often thought of as perfectly smooth rounded pieces they're really not.  There are various bulges, depressions, and holes that allow muscles and tendons to attach and join.

        Bones and cartilage are everywhere in the body.  There are three types of cartilage Hyaline, Elastic, and Fibrocartilage.  Hyaline cartilage is biggest portion of of skeletal cartilage.  It not only supports but is  resilient and flexible.  It can also be seen in articular, costal, respiratory, and nasal cartilage.  Elastic cartilage is quite similar to hyaline but is seen more in the epiglottis and ear areas.  Finally Fibrocartilage, this cartilage contains collagen fibers and is thus one of the strongest types of cartilage.  This type of cartilage is found in the knee as well as the intervertebral discs.  In order to create cartilage it must go through 3 phases, Appositional, Interstitial, and calcification.

             The bones of the body are classified into many sections.  Axial are the bones of the skull, vertebra, and ribs.  Appendicular, like the name implies, make up the appendages-arms and legs.  They are then classified by shape.  Long Bones are obviously longer than they are wide.  There are then short bones that can be cube shaped these can be found in the wrist and ankle areas.  Flat Bones are tin and...flat, and occasionally curved.  Lastly Irregular bones, which are basically everything that can't fit into any of the other categories.  These bones are oddly shaped and complicated.  

        There are many, many markings on the the bones which include: Tuberosity which is a rounded projection, Crest a narrow ridge of bone, Trochanter a large blunt irregular surface, and Line a ridge of bone.  Tubercle is a small rounded area, Epicondyle is the raised area above the condyle, a Spine is a sharp area, and Process is obvious prominence.  The Head is a bony expansion carried on a narrow neck, a Facet is a smooth flat area, a Condyle is a rounded projection, a Ramus is an arm like bar of bone.  The Meatus is a canal, Sinus is a basic cavity, Fossa is a basin like depression, a Groove is a furrow, a Fissure is narrow slit, and the Foramen is a round opening in bone.

               Bones are also classified with textures such as compact bone which is the dense outer layer, and spongy bone which is honeycomb like.  Bones are then classified into structures such as long bones that consist of diaphysis and an epiphysis, diaphysis is a shaft that forms the axis of bones.  Epiphyses are the expansions of long bones the inside is spongy and the joint surface is covered with articular cartilage.  The epiphyseal line separates these two sections.  The structure of short, flat, and irregular bones is, on the other hand, quite different.  They are thin sections of periosteum covered in compact bone on the outer section with endosteum, on the opposite side is spongey bone.  These bones do not have diaphysis or epiphyses and contain marrow between the trabeculae.  The microscopic strucure of the compact bone is the aversion system or the structural unit.  The Lamella is the weight bearing column, and the Haversian is the central canal that contains blood vessels and nerves.  Volkmann's canal are channels lying at right angles to the central canal connecting blood and nerve supply.  Osteocytes are mature bone cells and Launae are tiny cavities that hold the osteocytes.  And Canaliculi are hairlike canals that connect lacunae to the central canal.  Hydroxyapatites are mineral salts that make up more than half of the bone mass.  Since it's a salt it's mainly calcium phosphates which is thus responsible for the hardness of bones.  

          Bone development begins in embryos and doesn't stop until early adulthood, the process of of bone formation is called Osteogensis and Ossification.  Ossification forms most flat bones, the skull and clavicles.  This process is located mainly in the center of the fibrous connective tissues membranes.  The bone matrix is set within the fibrous membrane.  The woven bone and periosteum forms and the collar bone of compact bone forms and red marrow appears. Long bone's growth zone is when the cartilage cells undergo mitosis this results in the separation of epiphysis and diaphysis.  It then undergoes the transformation where old cells enlarge and the matrix becomes calcified.  The Cartilage cells then die and the matrix begins to deteriorate.  The Osteogenic zone is when new bone forms after the deterioration of the matrix.  Bone growth is most active during youth and adolescence.  The epiphyseal plate or growth plate is quite active.  When the person is fully grown the growth plate closes, or seals.


Spiral Fracture

           Obviously the stress we put our bodies under is tremendous.  Our bones are put to the test on a daily basis, some far more than others.  Which is why our bones simply give out under such stress.  Breaking bones isn't uncommon and they come in a whole array of forms.  Breaks can range anywhere from a tiny, but still painful, hairline fracture, to a compound fracture, which is most severe...and revolting.  Bone breaks are classified by the position of the bone after break, the completeness of the break, the orientation of the bone in comparison to the long axis, and if the bone penetrates the skin (compound).  Within these classifications there are more condensed classifications as to what type of break it is.  For example there is displaced and non-displaced also known as a dislocation, where the bone slips out of its typical position.  Complete and incomplete where the bone is either broken all the way through or not.  Linear where the bone breaks parallel to the axis of the bone, and Transverse where it is perpendicular to the axis.  Compound fractures penetrate the skin and Simple does not.  Typical types of fractures are Comminuted where the bone breaks into several pieces, ew!  A spiral fracture where it twists throughout the bone.  My dance teacher suffered this type of fracture just before she was to go to London to dance with the Royal Danish Ballet,  it's tragic, I don't know how she could have taken it so well, her career as a dancer slipping away so quickly...Anywho,  Depressed fractures are sections where the bone is pressed inward.  A compression is where the bone is entirely crushed, again ew!  Epiphyseal is where the epiphysis seperates from the diaphysis.  Greenstick is a partial break where the bone breaks some of the way through but not all the way, these are particularly common in children because their bone are so pliable.  A bone heals itself by first forming hematoma at the break this causes swelling.  Fibrocartilaginous then begins forming then granulation tissue forms finally capillaries begin to grow through again phagocytic cells begin cleaning.  All of this is typically done while the bone is supported/structured by a cast or splint of some sort in order the help the bone heal properly.

         Bone breakage is caused not only by serious amounts of force are placed on the bone but also an inadequate diet causing weakness in bones, this is called Osteomalacia.  Rickets are deformations in the bones, commonly seen in children.  Osteoporosis is when the bones become incredibly fragile and brittle.  This is caused when bone reabsorbing outpaces bone deposit.  Osteoporosis is most commonly seen in postmenopausal women.
       Bones can also believe it or not, bruise.  Bruising is caused similar to breaking where a huge amount of force is placed on a certain area.  Bruising typically occurs withing the marrow or withing the structures of the joints.  Several years ago when I was still competing in gymnastics I was warming up as I did every day.  We were going back and forth across the floor.  Our last warm up before we went to our events was a simple round-off, back handspring, back tuck.  When I came down out of my tuck I landed a bit funny, like I rolled out of it on my heels.  I felt an immediate sharp pain.  I have a fairly high tolerance for pain so I thought I would be able to just walk it off.  I tried rolling my ankle, thinking that maybe I just needed to pop it.  When I tried walking again the pain persisted.  I didn't want to be hurt I wanted to keep working out, but the pain in my heel was persistent.  So I was forced to condition on bars for the rest of the night.  I went home and lazed about.  When I needed to get up I forgot about my foot and tried bounding off of the couch, not my best idea, the sharp pain pierced through my heel again.  I lay on the floor a moment holding my foot, this is so stupid I thought.  Before too long I was taken to the doctor's office to have it looked at.  After quite a bit squeezing and poking and a couple of X-Rays the doctors concluded that I had damaged my growth plate.  They were unsure of what exactly I had done because the pain seemed to be right on my growth plates; and growth plates, until they are sealed, cannot be seen on an X-Ray.  It was most likely that I had either bruised it or received a hair line fracture.  They ended up suiting me up with a clunky boot for the next 3 weeks, not what I wanted.  After some of the injuries I've seen however, I should consider myself lucky.  I thought about adding a video here but then I thought, breaking bones is rather horrific, and I really have no intention of screening videos of people breaking themselves.  So I'm going to leave it up to you, the reader, to explore the world of these graphic examples on your own time. 

Integumentary System

         The integumentary system is the makeup of the skin, which is in fact the body's largest organ.  There are three layers of the skin consist of the epidermis, dermis, and hypodermis.  The epidermis is the outermost layer that acts as a barrier and thus protection, it is actually made up of many layers of dead skin cells, kinda nasty! There are four or five distinct cells types that lie in this layer. These cell types are keratinocytes, meloncytes, merkel, and langerhans.  Keratinocytes produce the protein keratin.  Meloncytes produce the brown pigment melanin.  Langerhans help with the immune system and Merkel are associated with sensory  nerve endings.  The deepest layer of the Epidermis layer consists of one row of keratinocytes.  The layers of the Epidermis layer are Stratum Spinosum, Stratum Granulosum, Stratum Lucidum, Stratum Corneum-this is the outermost layer that protects from moisture and the basic environment effects.    

          Beneath this layer is the Dermis layer.  This layer is a strong flexible layer made up of connective tissue.  The Dermis is only made up of two layers versus the four of the epidermis, these layers are papillary and reticular.  Within these layers are cells such as fibroblasts, macrophages, and occasionally white blood cells.  The reticular layer of the Dermis makes up nearly 80% of the skin's thickness!  Since it is so thick it acts as a strong barrier of the skin that can stretch and recoil.  The papillary layer is also quite elastic.    

          Finally below this is the hypodermis layer, the deepest of the layers in the skin.  Within this layers is adipose and areolar connective tissue.  

          Skin Color is effected by three basic pigments.  Melanin is the reddish brown/black color which is seen in most darker skin colors.  However, it can also be seen in freckles and moles where there is a build up of melanin.  The pinkish orange color on palms and feet are from the pigment found in Carotene.  Blushing or flushing, usually seen in our faces from working hard or emotions is caused from Hemoglobin, a pinkish red pigment.
          Sweat glands are found all over the body, from head to toe, literally.  The glands found in the palms, feet and forehead are all eccrine sweat glands.  Cerimonious glands are found in the ear and secrete cerumen. Apocrine glands are found in the axillary and anogenital areas.  And finally the Mammary glands, that as the name suggests, secrete milk.  These four types of glands all help with keeping the body from overheating.  Sebaceous glands are found all over the body and control sebum, an oily secretion.  These glands just like many of the others can become clogged and result in a rather nasty cyst if not taken care of.  Skin changes as a human grows.  During teen years sweat glands often over work and result in excess oil in the skin thus creating acne.  As the become elderly these glands slow, often too much, and result in scaly rough skin.

Melanoma.  EW!

           Now let's take it into cancers of the skin.  There are three major types of skin cancer Basal cell carcinoma, Squamous cell carcinoma, and Melanoma.  Basal is the most common of these three types.  This type of cancer takes over the dermis and hypodermic layers.  However, since it's slow growing and doesn't metastasize (spread) it can be cured quite easily with surgery.  Squamous cell carcinoma comes from keratinocytes of stratum spinosum.  It is found in the ears, around the mouth, and scalp.  This cancer unlike Basal grows very quickly and spreads if not taken care of.  This can be taken care of surgericaly or through radiation therapy.  Finally, there is Melanoma, the most serious and dangerous type of skin cancers.  Melanomas can be distinguished by their color, size, texture, and shape.  This type of cancer is highly metastatic and is resistant to chemotherapy.  There are some treatments that involve surgery and immunotherapy however, the chance of survival is low, especially depending on the size.
          Not only must the skin protect the body from the environment and face the possibility of cancer it must also take on the idea of burns.  Burns range in degree from 1-3.  Most everyone has endured a first degree burn that only damages the epidermis.  In second degree burns the epidermis and small portions of the dermis are damaged.  Third degree however, is where it gets nasty.  The entire thickness of the skin is damaged.  The skin is basically destroyed and takes ages to restore itself.  In third degree burns infection is the most important thing to worry about.

        Hair on the body is similar to much of the skin, in the since that, it's dead.  Hair is actually dead strands of keratinized cells produced by hair follicles.  Hair follicles project from an embedded root in the skin.  The center of the root is called the medulla, then the cortex and finally the outermost cuticle.  Hair is naturally colored at the bottom by melanocytes.  Hair helps with warmth as well as protection from environmental effects like sunlight, heat loss, insects etc.   And lets face it, hair is very important in physical appearance!  Which is why balding, or Alopecia is rather sad.  It is natural however, for human's  hair to become thin and fall out as they become elderly.
          The Integumentary system is obviously a huge part of the human body.  It protects against the harmful rays of the sun, fights against infection, helps regulate temperature, and really, holds us all together.  Keep it healthy!
       
          

Organization of the body parts

The body is organized into various hempisheres and planes each performing their own function that then allows another sections to work and function properly. The following illustrations and descriptions should give you an idea of how the body is sectioned off:

Directional:

There is superior and inferior. Superior is the upper part of the structure and inferior, as the name suggests, is below the superior section of the structure.

Anterior and Posterior are the back and front of the body as if it were cut down the middle so that your chest was anterior and your back was posterior. However, it can also be said that there are smaller parts to this like, your nose is anterior to your eyes-your nose is infront of your eyes.

Medial is the line running through the middle of the body that pertains to the inner part of the body. Lateral is opposite of medial, it's the outer parts of the body. Intermediate is between the medial and lateral sections.

Proximal is everything running from the bottom of a structure up. And distal is of course the opposite, top to bottom.

Superficial is the skin or outer layer of the body. Deep covers all of the internal parts of the body, organs and such.

These terms can be remembered simply by braking down the name into basic parts. This naming system is similar to most any part of the body.

Planes:
-Frontal divides the body into anterior and superior (front and back.)

-Sagital into left and right.

-Medial lies on the midline.

-Transverse runs horizontally and divides the body into superior and inferior (Upper and lower)

-Oblique is sectioned off diagnally.

Within the body we have cavaties. Cavities are sectioned off spaces of the body. These cavities include the dorsal cavity, the long section running from the back of head down the spine/back. Since it covers the back it thus lies in the posterior plane. This can be remembered by thinking of fish or sharks, the dorsal fin is always on their back. The spinal cavity is of course right below this where the spine lies. The cranial cavity is at the top of the dorsal cavity, and like the name implies is of course the skull.

The ventral cavity is from the top of the chest, just below the neck, down to the pelvis. This cavity lies within the anterior plane. The ventral cavity is made up of the thoracic cavity which covers everything inside the ribcage such as the lungs and heart. Below this (inferior) is broken down once more within the ventral cavity into the abdominopelvic. Within this is the abdominal cavity which contains organs like the kidneys and spleen. And below this is the pelvic cavity which includes the reproductive organs and bladder.

Tissues

Homeostasis

Homeostasis (homeo=similar, stasis=staying), or staying the same includes the regulation of the temperature and of the food, salt, and gas content of the fluid bathing all cells. Really, the body's ability to adapt to changing conditions. When the body is heated or cooled it uses homeostasis to balance itself again. Both animals and humans perform homeostasis. For example dogs pant to cool themselves down while humans sweat instead to lower their temperature. Homeostasis not only regulates the body's temperature but also the chemical composition of the body fluids. Homeostasis is totally different and personal for each individual. Various factors come into play with homeostasis. For example, a person's weight, metabolism, and clothing all effect temperature regulation. There is also negative feedback from homeostasis Which prohibits the body from working. Regulating temperature, like shivering to warm up is a good example of negative feedback. Positive feedback on the other hand allows the body to exceed its expectations. An example of positive feedback would be blood clotting as the result of a cut. In a way things are both good and bad.

Homeostasis Lab

Our homeostasis lab didn't go exactly to planned every second but we learned form those mistakes and corrected them. Our experiment to test homeostasis was to see how long it would take each of our bodies to return to their normal temperatures after being cooled and then after being heated.  We used two girls and two boys to compare.  First we recorded the normal temperature of our bodies.  We then placed our hands in ice water and kept them there for one minute. We then timed ourselves to see how long it would take for our hands to return to their original temperatures. We then repeated the experiment but used hot water instead. For some of us it took ages to return to our normal temperatures and for others it only took a few minutes. Over all it seemed the boys' homeostasis worked much faster than the girls'.

This experiment only tested a portion of our bodies.  This would be quite a bit different if it were the entire body.  In fact, my own Mother experienced hypothermia during a river rafting trip.  My mother used to run rivers constantly.  One of her many trips though went very wrong.  The group had just started out when my mother was bumped out of the boat into the extremely cold choppy waters.  Just before the trip the group had been told that people don't die from inhaling too much water but drinking too much.  As my mom was swept down the river she was continuously dunked under the water and unintentionally gulped down the frigid water.  She was not only drowning to some extant, but freezing herself inside and out.  She rode down the river following the raft for nearly four miles.  The team managed to pull the raft onto a bank and fling her a rope to pull her to shore.  Once on shore she could hardly breath much less move.  At first she was just numb and somewhat delirious.  Once she had sat in the sun for a few moments she transitioned into uncontrollable shaking.  Though the shaking had begun to relax, her hands and feet still didn't have full dexterity and her color hadn't changed from the purply blue.

My mother of course became numb because any heat had been drained from her body, everything froze up, including her brain.  When she began shaking, it was her body's response to the cold; it was making an attempt to warm itself up-homeostasis.  Her hands and feet were the last to return to normal because the core of the body will warm fastest and spread outward.  My mom believes it took her about forty-five minutes to return to a fairly normal temperature and over an hour to return to a totally normal temperature.  And this was after changing into dry clothes and sitting in the sun directly after getting out of the water.

My mother's experience was basically a large scale version of our experiment.  I think hearing this real life story helped me not only understand homeostasis but also the real danger you can put your body into in extreme heat-hypothermia and extreme cold-hypothermia plus the possibilities of long term effects.