Chewing Lab

In this class, we did a chewing lab to see what foods took longer to chew, and how long it actually took someone to chew something. It was a pretty neat thing to do, especially being one of the test subjects, eating all of the yummy food! :) We had people bring in many different foods to test. The person I just so happened to chose was Whitney, and the graphs I did of her were her PB and celery, pickle, and chips and guac. We had a EKG plugged into the computer and had electrode tabs on the test subject and cords running from the tab to the EKG box. When making my graph, I simply just went to the highest point on each graph, and the lowest point and subtracted the two to get the averages.

Here is one of the graphs that I used to get the data from:

Here is a graph of Whitney's Data:

This was a pretty fun lab to do. It was cool to compare the different foods and see what foods take more to chew than others!

Bones

      As you know, bones are a huge part of your body and play a major part in the things you do everyday. Your bones are pretty much the main thing that run your body. Your bones are connected to everything, and they help you move to do the everyday things that you do.
       There is more to bones than just bones though. There is skeletal cartilage which contains no blood vessels, and is surrounded by the perichondrium that resists outward expansion. There are three types of cartilage and they are- hyaline, elastic, and fibrocartilage.  There are also different growths of cartilage. There is appositional, and interstitial. Appositional is where the cells in the perichondrium secrete matrix are against the external face of existing cartilage. Interstitial is where the lacunae-bound chondrocytes inside the cartilage divide and secrete new matrix, expanding the cartilage from within. Calification of cartilage occurs during normal bone growth and during old age.

     There are two classifications of the bones and they are Axial skeleton, and Appendicular skeleton. Axial are bones of the skull, vertebral column, and bones that are in the rib cage. Appendicular are bones that are the upper and lower limbs, shoulder, and hip bones. There are also bones that are classified by their shape. There are long bones, which are longer than they are wide, short bones, which are cube shaped bones like the wrist and ankle. They are also bones that form within tendons. Flat bones are thin flattened bones that are curved a little. Mostly in the sternum and skull. Irregular bones are bones with complicated shapes such as the vertebrae and the hip. 

      Bones have many functions. Bones are defiantly here for support, forming the frames that support the body and protect soft organs that are in the body. They Protect. The provide a case that protects the brain, spinal cord, and vital organs. The help you to move, providing levers for your muscles. Believe it or not, your bones also store minerals, mostly calcium and phosphorus. Your blood cells also form in your bones. Hematopoiesis occurs in the marrow cavities of your bones. 

      Your bones can be classified as two different of textures. There is compact bone, which is the dense outer layer, and there is spongy bone which is honeycomb trabeculae filled with yellow bone marrow.

Your bones have membranes. Periosteum, and Endosteum. Periosteum is a double layered protective membrane. THe outer fibrous layer is dense regular connective tissue, the inner osteogenic layer is made up of osteoblasts and osteoclasts. It is richly supplied with nerve fibers, blood, and lymphatic vessels that enter the bone via nutrient for mania. They are secured to underlying bone by Sharpey's fibers. Endosteum is a delicate membrane covering internal surfaces of the bone. Red marrow is also in your bones. In babies, it is found in the medullary cavity and all the areas of spongy bone. In adults, it is found in the dipole of flat bones, and the head of the femur and humerus. 

      Your "Bones" begin to develop at week 8 of embryo development. 

Muscle project

For our project on muccles, I made a poster on the Neuromuscular Junction. The Neuromuscular Junction's Function is to transmit signals from the motor neuron to the skeletal muscle fibre quickly and reliably, to ensure percise control of skeletal muscle contraction, and voluntary movement.


Here are a few pictures of my poster :)

Skeleton Contest Review

At first I was a little nervous about remembering all the things I need to remember about the ribs and pelvis. But once you go over them over and over agin you start to remember them and it just gets easier, and easier as you go. Doing the contest, I got most of my bones labeled right, and even though we came in second to last place, I'm still pretty proud of our group :). 

      As i said before, I had to do from about the neck down all the way to the pelvis. I labeled the clavicle, scapula, sternum, manubrium, costal cartilage, the xiphoid process, true ribs, false ribs, floating ribs, and so on. We ended up getting 79 on the contest. WHOOO-HOOOO GO GROUP 1!! ;)

Integumentary System

The Integumentary System (Integument) better known as skin consists of three or more mayor regions. You're skin actually goes a lot deeper than you think. The three regions of the skin are the epidermis, dermis, and hypodermis. The epidermis is the outermost superficial region, the dermis is the middle region, and the hypodermis (superficial fascia) is the deepest region of the skin.

      The epidermis is composed of keratinized stratified squamos epithelium, that consists of four different cell types and four of five layers. The cell types include kerationocytes, melanocytes, Merkel cels, and Langerhan's cells. The outer portion of the skin is exposed to the external environment and functions in protection. Since the epidermis is the top layer of skin, you shed skin every day without even knowing it! In the epidermis, there are different layers within it. The first is the Stratum Basale layer, usually just known as the Basal layer. It is the deepest epidermal layer, attached firmly to the dermis, and also consists of a single row of the youngest keratinocytes. The cells in the Basal Layer undergo rapid division. The next layer in the epidermis is the Stratum Spinosum, a.k.a the Prickly Layer. The cells in this layer have a weblike system of intermediate filaments attached to desmosomes. Melanin granules and Langerhans' cells are really big in this layer. The layer after that is the Stratum Granulosum (Granular Layer). This layer is a very thin layer that has three to five cell layers in which major changes in keratinocyte appearance happens. Keratohyaline and lamellated granules build up in the cells of this layer. Next is the Stratum Lucidum a.k.a as the clear layer. This layer is a very thin, transparent band superficial to the stratum granulosum. It is a few rows of dead, flat keratinocytes. It is only present in thick skin. The last layer of the epidermis is the Stratum Corneum a.k.a the Horny Layer, yes i know that is a funny name. This layer is the outermost layer of keratinized cells, and it accounts for three quarters of the thickness of the epidermis. It's functions include: protection from abrasion and penetration, waterproofing, and rendering the body relatively insensitive to biological, chemical, and physical assaults.
     The next major layer below the epidermis is the Dermis that has strong, and flexible connective tissue. The cels in this layer include fibroblasts, macrophages, and sometimes have mast cells and white blood cells. This layer consists of two layers, papillary and reticular. The papillary layer has Areolar connective tissue with collagen and elastic fibers. Its surface has peg like projections called dermal papillae. Dermal papillae contains capillary loops, Meissner's corpuscles, and free nerve endings. The reticular layer accounts for about 80% of the thickness of the skin, and has collagen fibers that add strength and resiliency to the skin. Elastin fibers provide stretch-recoil properties.
     The Hypodermis is the deepest layer of your skin, and it is composed of adipose and areolar connective tissue.
      Have you ever wondered why your skin is the color that it is? There are three different pigments that contribute to your skin color. Melanin is one of them. Melanin is a yellow to reddish-brown to black pigment that is responsible for darker skin colors. That's why when you see melanoma cancer, the  spots are really dark. Freckles and pigmented moles are also build ups of melanin. Carotene is another pigment that is yellow to orange, and is usually most obvious in the palms and soles of your feet. Hemoglobin is a reddish pigment that is responsible for the pinkish look of the skin.

 

 Sweat glands are a pretty big part of the body, and there are different types that prevent overheating of the body that can secrete cerumen and milk. The eccrine sweat glands are found in the palms, the soles of the feet, and the forehead. Apocrine sweat glands are found in axillary and anogenital areas. The Ceruminous glands are modified apocrine glands that are in the external ear canal, and secrete cerumen. This may be surprising, but the mammary glands are actually specialized sweat glands that secrete milk. Sebaceous glands are simple glands that are found all over your body. They soften your skin when stimulated by hormones, and secrete an oily secretion called sebum.
      Now that you know the normal functions of the skin, lets talk about the things that can go wrong with your skin. I'm going to talk about Albinism. Albinism occurs when one of several genetic defects makes the body unable to produce or distribute melanin, which is a natural substance that gives color to your hair, skin, and the iris of your eye. It results in little or no color in your hair, skin, or eyes. The defects of albinism may be passed down through families. There are two different types of albinism: Type 1 albinism, and Type 2 albinism. Type 1 albinism is caused by defects that affect production of the pigment, melanin. Type 2 albinism is due to a defect in the "P" gene. People with this type of albinism have slight color at birth, but the most severe type of albinism is called oculocutaneous albinism. People with this type of albinism have white or pink hair, skin, iris color, and vision problems.  Another type is ocular albinism type 1 (OA1), which affects only the eyes. everything is usually in the normal range, but if an eye exam was taken, it would show that there is no coloring in the retina. HPS- Hermansky-Pudlak syndrome is a form of albinism caused by one single gene. It can occur with a bleeding disorder, as well as with lung and bowel diseases. The symptoms a person with albinism will have are:

• Absence of color in the hair, skin, or iris of the eye
• Lighter than normal skin and hair
• Patchy, missing skin color
• Crossed eyes (strabismus)
• Light Sensitivity (photophobia)
• Rapid eye movements (nystagmus)
• Vision Problems or functional blindness

 

  If you are worried that you have albinism, genetic testing offers the most accurate way to diagnose albinism. It would be very helpful if your family has a history of albinism.
     The goal for treatment of albinism is to relieve the symptoms, but the treatment you do depends on the seriousness of the disorder. It is very helpful to protect the skin and eyes from the sun. When exposed to the sun, use sunscreen and cover up completely with clothing, use sunscreen with the highest SPF, and use UV protected sunglasses.

Sources:

• http://www.nlm.nih.gov/medlineplus/ency/article/001479.htm
• http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002450/

Histology Lab

Homeostasis Lab

Learning about Homeostasis, our class got into groups and each group came up with their own experiment lab. Our group decided to do ice baths. While doing this lab, we measured the group member's weight, blood pressure and temperature before they got into the ice bath. We had one girl (whitney) and one guy (Colten) get into the ice bath for 10 minutes and then get out and we measured the same things again besides the weight.



Data: Male- weight 170, heart rate- 60 before, 50 after. Temperature- 98.1 before, 98.3 after.
Data: Female- weight 125, heart rate- 70 before, 60 after. Temperature- 99.4 before, 97.5 after



Conclusion: After doing this lab, I see that taking an ice bath and going straight from normal temp to  cold things in your body change. All the different systems in your body go crazy (well not really  crazy) but they all have different readings and they change. Watching Whitney and Colten get into the ice bath, they entered slowly and as soon as they got low enough into the water, they couldnt breathe.

Homeostasis

I bet that when you hear the word homeostasis, you probably wonder what it means. I know that when I first heard it I wondered what it meant. Homeostasis is the ability to maintain a relatively stable internal environment In an ever-changing outside world. The internal Environment Of the body is in a dynamic state of equilibrium, so chemical, thermal, and neural factors interact to maintain homeostasis. Most homeostatic is controlled by the release of hormones into the bloodstream.
      With Homeostatic Control Mechanisms, the variable produces a change in the body. The three interdependent components of control mechanisms are the receptor, the control center, and the effector. The receptor monitors the environments and responds to changes (stimuli). the control center determines the set point at which the variable is maintained. And the effector provides the means to the stimulus.
    This is a chart that kind of puts the control mechanisms into a better understanding for you.

     Watching a video in our Anatomy and Physiology a couple days ago showed us some of the things that homeostasis deals with. They were showing a race and all the the things you need to keep track of when you are running a marathon rice like that. There are actually more things that go to it when you are talking about your heart rate, temperature, weight, fuel for glucose levels, and breathing. They kept track of one particular woman's levels throughout a race and everything was pretty good throughout the race, but towards the end some things started going a little wrong. She stayed hydrated through the race and was well hydrated before the race. At the end she had lost five pound from sweating all her hydration off and all of her rates started to go back to normal. When you are doing a physical activity like that you have to know that all of your levels of heart rate, temperature, your breathing rate, glucose levels and everything are either going to drop or rise, but most likely rise. When all of your levels or rates start to go back to normal that isn't always the best thing because that is called negative feedback. In negative feedback the output shuts off the original stimulus.

There is also something called Positive feedback. With positive feedback systems, the output enhances or exaggerates the original stimulus. An example of this would be the regulation of blood clotting. With this  there could be a break or tear in the blood vessel wall which causes the feedback cycle to initiate. The clotting occurs as platelets adhere to site and release chemicals. Then the feedback cycle just ends. Released chemicals start to attract more platelets, The clotting then proceeds until the break is sealed by a new clot that forms. And thats pretty much how a positive feedback cycle works.
     There is also something called Homeostatic Imbalance. With homeostatic imbalance there is a disturbance of the bodies normal equilibrium. It pretty much goes crazy! Overwhelming of negative feedback mechanisms allow destructive positive feedback mechanisms to take over. This is definitely something that you don't ever want to happen!