How Our Tissues Function and Why
By: Charlotte Adams
Epithelial, Connective, Muscular, and Nervous Tissue
Have you ever thought about how our tissues work or why they work? Have you ever thought about their form/function and relationships? Well if you have I am going to help you out and explain it in this one short flyer!
Epithelial Tissue
Let's start off with Epithelial Tissue, because it's one of the easier ones to identify and explain. We can find this tissue covering the inside and outside of our bodies. Epithelial Tissue has four functions which are to protect, to absorb, to filtrate and excrete, and to have sensory perception...if innervated. You are probably wondering why this is. To make the answer short and sweet, it's because Epithelial Tissue is classified in two different ways: shape and arrangement. There are three shapes known as squamous, cuboidal, and columnar and they are arranged in two different ways: simple and stratified. The cell arrangement has more to do with the Epithelial Tissue's functions. Simple arrangement is a single layer of cells that absorbs and filtrates inside the body. On the other hand, stratified arrangement is stacked cell layers that protect against abrasion or rubbing found on the skin surface and in the mouth. These arrangements allow the Epithelial Tissue to function correctly and efficiently during our daily lives. Below you can see a picture of the different types of Epithelial Tissue.
Simple Squamous
Single layer of cells that are flat and scale-like.
Stratified Squamous
Stacked layer of cells that are flat and scale-like.
Simple Cuboidal
Single layer of cells that are cube-shaped.
Stratified Cuboidal
Stacked cell layers that are cube-shaped.
Simple Columnar
Single layer of cells that are tall and elongated.
Pseudo Stratified Columnar
This one is tricky! The cell appears to have many layers but actually is only comprised of one layer. It is an illusion because of the positioning of the nuclei within the cell.
Connective Tissue
Connective Tissue is more tricky because there are so many types of tissue that perform its function. I am going to try to make this as short as possible and to the point. For starters, let me talk about the six main functions of Connective Tissue. It connects, binds and supports structures, protects and cushions organs and tissue, can bear weight, stretch, and take abuse, insulates and stores fat, transports substances, and provides framework and protection. That is a lot to take in so let me break it down. There are five connective tissues that perform these functions. Going in order from most to least dense would be bone, cartilage, dense connective tissue, loose connective tissue, and blood. The bone is to support and protect, store minerals, and keep the flow of blood and cell production constant. Cartilage can be broken into three types: hyaline (provides smooth surfaces), elastic (provides support to surrounding structures and helps define and maintain the shape of the area in which it's present), and fibrocartilage (provides support and rigidity to attached/surrounding structures). Dense Connective Tissue can be broken up into two categories: Dense Regular Connective Tissue (resists pulling forces) and Dense Irregular Connective Tissue (forms the capsules that surround our internal organs). The Loose Connective Tissue breaks up into three parts like Cartilage: the Areolar (cushions organs and holds them together), the Adipose (stores energy, protects, and insulates), and the Reticular (provides internal supporting framework for organs). As you can see, Connective Tissue does a lot of protecting, supporting, and connecting, allowing our bodies to work appropriately during our day to say lives.
Dense Irregular Connective Tissue
Loose Connective Tissue
Blood
Muscle Tissue
This is the easiest and shortest type of muscle to understand how it functions and what gives it the ability to. Muscle Tissue provides posture and body support, the ability to move (walk), and heat production. There are three different types of muscle tissue and are classified as either voluntary (conscious) or involuntary (unconscious). The first is skeletal tissue, which allows for body movement and is a voluntary action. The second is smooth tissue and it moves the blood, food, and waste through our body's organs and is an involuntary action. The third is cardiac tissue, which keeps our heart beat's contractions constant. These three muscle types allow for all of the functions of our Muscle Tissue to work efficiently and corporately.
Nervous Tissue
Nervous Tissue is more self-explanatory than the other three tissues. Therefore, this information is going to be short and brief. So let's get started. The two main functions of the Nervous Tissue are...
- Generate and transmit nerve impulses to and from the body organs via neurons
- Support, insulate, and protect neurons
Which Tissue Is Best For Its Location and Function and Why?
This is really a matter of perspective question. However, I believe the best tissue in our bodies is the Muscular Tissue...that may be because I love to move around. To refresh your memory, Muscular Tissue provides posture and body support, the ability to move (walk), and heat production. The three types, skeletal, smooth, and cardiac, are located in areas that allow for these functions. Skeletal muscle is found around our large body muscles which allows body movement. This is a voluntary (conscious) action because we move when we want (think) to move. The Smooth muscle is located around our organ walls and blood vessel cells, allowing blood, food, and waste to flow easily through our bodies. This is an involuntary action because no one thinks, "I want to move my blood down my body"...it just happens because of the Smooth muscle. The last one, Cardiac muscle, is found around our heart walls to help keep our heart's contractions constant and synchronized. It is an involuntary action because again, no one is thinking to keep their heart at constant beats. This is why I think the Muscular Tissue is the best for its location and function. Without any of these three muscles types we would not be able to move! Again, this is a question depending on your point of view, but at least you now have an insight about how I feel.