Skeletal Muscle Tissue

This is a picture of a typical but very complicated skeletal muscle tissue. This picture is a very basic view, there are actually a lot more to go with this, but for now I will discuss the basics to this muscle. This tissue is key to being move, when it contracts or expands it allows us to move. Skeletal muscles are often called voluntary muscle since its the only type you can control subconsciously, and is responsible for your overall body mobility. It is also the main component in keeping our body warm. As it contracts rapidly it produces heat, and we store this heat to keep us warm. There are hundreds of tiny parts to this muscle that result in our movement, here are a few of the important ones and what they actually do.

The Fascicle - The fascicle is part of the muscle that is a discrete bundle of muscle cells, it is actually segregated from the rest of the muscle by a connective tissue sheath. It is surrounded by a perimysium.
Muscle Fiber - It is an elongated multi nucleate cell, which has striations, which is basically just a series of color changes in bands. It is surrounded by the endomysium.
Myofibril - It is a complex organelle composed of bundles of myofilaments, they occupy most of the muscle cell volume, and appear banded, like striations. It is composed of sarcomeres arranged from end to end.
Sarcomere - It is a segment of a Myofibril. The contractile unit, composed of myofilaments.
Myofilament - It is an extended macromlecular structure that has thick and thin filament that contain bundled myosin molecules. The thin filaments contain actin molecules as well as proteins.

This is basically the larger and more detailed version of the picture above, but shows a lot more of the tissue that I have no idea what they do. But they all contribute to our body movement in one way or another.

EKG Food Lab

Bone Fractures



Comminuted Fracture

 Comminuted fractures tend to be fractures that broke into three or more peices, the one above is more like 6 peices. It is common in the elderly since their bones are often brittle and weak.

Complete Fracture

 Complete fractures are fractures where the bone is broken all the way through rather then ones like greenstick that are still connected.

Compound Fracture

Compund fractures are the nastier of the bunch, compund meaning that the bone breaks through the surface of the skin. Common when there is an extreme force on a section of the bone and it snaps quickly and sends one end up.

Compression Fracture

A compression fracture is when the bone is crushed rather then broken. It is common in people who have osteoporotic bones, or those that have been subjected to to extreme trauma in a fall.

Depression Fracture

A depression fracture is typically in the skull. Its when a broken bone is pressed inward. The inward press on a skull also has a good chance to leave a compound fracture too.

Displaced Fracture

A displaced fracture is when bone ends are out of normal alignment and usually have to be set again.

Epiphyseal Fracture

Epiphyseal fractures is when the Epiphsis seperates from the diaphysis along the epiphyseal plate. Tends to occur when cartilage cells are dying and calcifaication of the matrix is occuring.

Greenstick Fracture

Greenstick is a very common type of fracture in children since thier bones are not fully developed and still bend a bit. The bone breaks incompletely, only one side of the shaft breaks;the other side bends.

Incomplete Fracture

Incomplete fracture is when the bone is not broken all the way through, this is basically the same as a greenstick fracture.

Linear Fracture

Linear fractures is when a fracture occurs along or parallel to the long axis of the bone.

Non-Displaced Fracture

Non-Displaced Fracture is like a hairline fracture, the bone doesnt completely break and it remains in its normal position.

Simple Fracture

Simple fractures are very common, its just when a fracture occurs and the bone doesn't penetrate the skin.

Spiral Fracture

Spiral fractures are very common with sports injury's. A break occurs in a twisting motion and ragged ends are made.

Transverse Fracture

Transverse fractures are fractures that are through the bone. Unlike Linear fractures they occur perpendicular to the long axis of the bone rather then parallel to it.

Article on Tissue Engineering Research

http://www.pbs.org/saf/1107/features/body.htm

The link above is to a site where it talks about all the recent research that has been going on in tissue engineering. Reseachers and engineers from all over the world have came together for the common goal of offering a solution to the everyday diseases and problems our bodies may run into. They have began to engineer ears on specially bred mice. They do this by impanting a scaffling of young cartilage on the back of a mouse that is hairless and has no immune system so it wont reject the ear. The mouse then nourishes the ear and when it is fully grown and molded the ear can be removed with little harm to the mouse. This is just a small step, in the future researchers hope to be able to make virtually anything. Ultimately their goal is to improve human life expectancy by engineering organs, cartilage, and bone.

I was very surprised when i read the article, I didn't have any idea that this was going on in the world. I think it is a great way to help people with terminal diseases. Surprisingly to me this research has been allowed by the vatican, which has denied many things like this in the past because they saw it is an ethical issue.

Tissues

These pictures represent the different types of tissues found throughout the body. We took these pictures in my 6th hour class.

Pseudostratified Columnar Epithelium

Has cells of different heights and sizes, this gives the false

impression that it has several layers.

Found in the lungs and other places where mucus needs to be

pushed away.

Simple Columnar Epithelium

Seen as a single layer of tall, closely packed cells. Mostly used

for absorption and secretion.

Found in tubes and other passage ways.

Simple Cuboidal Epithelium
Made of tall and wide cells arranged in single a single layer.

  Important function is secretion and absorption.

  Forms the walls of small ducts of glands and kidney tubules.

Simple Squamous Epithelium

Flat single layered cells that are laying laterally, their goal is

to reduce friction.

They are found in the air sacs in the lungs, the lymphatic

system, and the lining of the heart.

Stratified Columnar Epithelium

Very limited in the body, but occur at transition areas.

Found in the pharynx, the male urethra, and lining of some

glandular ducts.

Stratified Cuboidal Epithelium

 Typically two layers of cuboidal cells.

Rare in the body, found in sweat and mammary glands. 



Stratified Squamous Epithelium

Single layered cells, the lining reduces friction.

Forms the skin and a short distance into every body opening.

Transitional Epithelium

Several different layers of different cell types. Surface cells

are dome like and can stretch. The basal cells are cuboidal

or columnar.

Found in the lining of hollow urinary organs.

Homeostasis Lab

Organization of the Body

Here are the different organizational levels of the body.

There are six different organizational levels which all contribute to the complexity of the human body. They range from tiny things not visible to the human eye, to your body. All of these levels have a relationship to each other in one way or another.

1. Chemical Level - This is the simplest level of the structural pyramid. It consists of other units like atoms, molecules, macromolecules, and organelles.
1. Atoms - Atoms are the tiniest building blocks of matter, they combine to form molecules.
2. Molecules - Molecules are two or more atoms that are formed together by a chemical bond, they form organelles.
1. Macromolecules - Macromolecules are very large molecules that form different polymers.
3. Organelles - Organelles are the basic components that make up the microscopic cells.
2. Cellular Level - The cellular level consists of many different types of cells that help form tissues.This is the level that the simplest living creatures stop at.
3. Tissue Level - Tissues are groups of cells that all have cells with similar functions. There are four different kinds of tissues in the human body.
1. Epithelium - Covers the body surface, lines the internal cavities, and forms glands.
2. Muscle - Provides movement to our bodies
3. Connective - A primary tissue; form and function vary extensively. Functions include supprort, storage, and protection.
4. Nervous - Provides a means of rapid internal communication by transmitting electrical impulses.
4. Organ Level - Organs are all made up of different types of tissues. This level allows extremely complex functions to become possible.
5. Organ System Level - Organs that work together to accomplish a common purpose make up an organ system.
6. Organismal Level - This is the highest level of organization, and an example would be the human body. It represents the sum total of all structural levels working together to pursue the continuance of life.

Medical Terminology

Homeostasis

Have you ever been running on a hot day and started sweating? Or out in the snow and started to shiver? Do you know why your body does either of these? In fact these are just two of the many things that your body can do to maintain a normal body temperature. Homeostasis is the ability to maintain a relatively stable internal condition even though the outside world is a ever changing environment.



Everyone sweats and many may think that it makes you hotter, but it actually makes you cooler. It is our bodies easiest way to cool down, and without it we wouldn't be able to stand the heat our body gives off naturally. We all sweat throughout the day and even when we are doing simple activities like laying down or watching TV, basically you sweat for a good portion of the day. That is why you are supposed to drink at least a liter of water a day. Because when you are running on a hot day you can have as many as two million sweat glands trying to cool your body down.



I've always thought that shivering was one of the weirdest functions a body went through, but it actually has a purpose. It is triggered by the brain, which constantly sensors our temperature, and if we get to cold we shiver to warm up. Shivering is actually when the muscles expand and contract quickly, which burns a lot of energy and is usually the bodies last resort to get to a normal temperature. Another way the body stays warm is by increasing metabolism, just another way to burn energy and produce heat.

Without Homeostasis we would all inevitably overheat and die, or die of hypothermia. It is one of the many amazing functions the body has though, thankfully it is a subconscious function that we don't have to monitor.



This is what the body does to maintain a normal homeostasis.