Lesson Six: Muscular System (Part Two)

Muscular System

(Part Two)

Think Quest

Structure
We all know that living organisms can move on their own or can perform other types of movement.
Muscle tissue has a ability to relax and contrast and so bring about movement and mechanical work in various parts of the body.
There are other movements in the body too which are necessary for the survival of the organism such as the heart beat and the movements of the alimentary canal.

 ~ Muscles can be divided into three main groups according to their structure ~

Smooth (Visceral) Muscle Tissue:

Visceral muscle, is found in various parts of the body such as the arteries, the bladder, the digestive tract, as well as in many other organs.

Visceral muscle is also called smooth muscle because it doesn't have cross striations. Visceral muscle contracts slower than skeletal muscle, but the contraction can be sustained over a longer period of time.

Skeletal Muscle Tissue:

Skeletal muscle, which is attached to bones by tendons, is associated with the body's voluntary movements. Skeletal muscle is striated muscle. Unlike cardiac muscle, the cells are not branched.

 

Cardiac Muscle Tissue:

Cardiac muscle is so named because it is found in the heart. Cells are joined to one another by intercalated discs which allow the synchronization of the heart beat. Cardiac muscle is branched, striated muscle.

Interestingly, adults have a certain number of muscle cells. Through exercise, such as weight lifting, the cells enlarge but the overall number of cells does not increase.
Skeletal muscles are voluntary muscles because we have control over their contraction. Visceral muscles are involuntary since, for the most part, they are not consciously controlled.

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Homework Time:

1-Draw and label one of the Muscle Tissues

Announcements

Announcements

Dear Students,

I would like announce with this post that our lovely school will be close for the coming few days for some maintenance.

I'll to send some homeworks by email that to be done by next week.

Regards,

Tariq

Lesson Five: Muscular System (Part One)

Muscular System

(Part One)

encognitive

The human body contains more than 650 individual muscles which are attached to the skeleton, which provides the pulling power for us to move around. 

The main job of the muscular system is to provide movement for the body. The muscular system consist of three different types of muscle tissues : skeletal, cardiac, smooth. 

Each of these different tissues have the ability to contract, which then allows body movements and functions. There are two types of muscles in the system Voluntary Muscles: The muscle in which we are allow to control by ourselves. Involuntary Muscles: The muscle in which we can't control; The heart, or the cardiac muscle, is an example of involuntary muscle.

Homework:

Q1. what is the main job of the muscular system

Q2. Provide me with a couple of examples of the Voluntary and the Involuntary Muscles

Annunciation Day

Dear All,

 

This to announce that Annunciation Day, Thursday, March 25, 2010 will be observed as a holiday.

Regards 

Lesson Four: Circulatory System (Part Two)

Circulatory System

(Part Two)

The Life Pump

About every two minutes, the average adult's quarts of blood through 100,000 miles of blood.

Working together, your heart, lungs, and blood vessels form a life pump known as the circulatory system.

Quite simply, this transportation system sends blood to every part of your body. When blood is pumped through your heart into your lungs, the red blood cells load up on oxygen and are then pumped back to the body full of life-giving oxygen. Then the system turns around and acts as a garbage truck, carrying toxins from throughout the body for disposal.

There are three distinct parts of the circulation system:

1- The pulmonary system moves the blood from the heart into the lungs, where red blood cells are infused with oxygen in exchange for carbon dioxide, and then back to the heart

2- The coronary system provides blood specifically to the heart.

3- The systemic system moves blood throughout the body using arteries, veins, and capillaries.

Oxygen-rich blood leaves the heart in arteries and returns to the heart in veins. Capillaries connect these arteries and veins. Arteries send oxygenated blood to the capillaries. In turn, these small blood vessels deliver the red blood cells to every nook and cranny of your body. The capillaries then collect the oxygen-depleted blood and waste products and funnel it into the veins for the return trip to the heart and lungs for another load of oxygen.

During this trip from and back to the heart, your blood flows through your kidneys (renal circulation) where much of the waste is filtered from your blood and your small intestine and liver (portal circulation) where sugars are filtered from the blood and stored for later use.

Homework Time:

Q1:Talk about the distinct parts of the circulation system in few sentences.