Smooth muscles are also known as involuntary muscles, meaning that a person cannot physically chose to move them. Instead, smooth muscles are controlled in the background by brain and body. An example of smooth muscle is the digestive system, where muscles in the contract to squeeze food down to the stomach or tighten when you have an illness so that you are sick. Other examples of smooth muscle include the bladder and the muscle behind the eyes that keeps your eyes focused. Smooth muscles are also found in the blood vessels, helping blood to move around the body.
Cardiac muscle is in your heart, also known as myocardium. Like smooth muscle, cardiac muscle is an involuntary muscle. These muscles are thick because they have to contract frequently to move blood in and out of the heart.
Skeletal muscles are the muscles that allow you to control the movements of your body, arms and legs, etc. These muscles are attached to your bones via tendons, which are like cords made of tissue. In order for you to move, your skeletal muscles, tendons and bones must all work together. Skeletal muscles come in different shapes and sizes – just compare the muscles of a weight lifter to your own!.
Other skeletal muscles in the body you may not be as aware of include those in the neck or face. Even your tongue contains skeletal muscles. Skeletal muscles often work in pairs, such as the biceps, which bend the arms, which work with the triceps, which straighten the arms.
In the video when the biceps contract the arm bends, when the triceps contract it straightens out again…
The digestive system consists of aseries of organs and glands that process the food we eat in order to convert food into energy. The body needs to break food down into smaller molecules that it can utilise the nutrients in food before excreting (getting rid of) the unusable components of food as waste.
Most of the digestive organs (like the stomach and intestines) are tube-like and contain the food as it makes its way through the body.
The digestive system is essentially a long, twisting tube that runs from the mouth to the anus, plus a few other organs (like the liver and pancreas) that produce or store digestive chemicals.
Without the digestive system, our bodies would not be able to get nutrients from the food we eat or get rid of the waste products that food makes and we would soon become ill!
Find out loads more about the digestive system here…
In the human heart diagram, there are four chambers in this tireless pumping organ. All the chambers work in coordination pump blood round the body.The left chambers contain the oxygenated blood from the lungs.
This blood is pumped out of the heart via the arteries which transport the this oxygenated blood round the body to the muscles and vital organs.
The blood returns to the heart via veins. The veins return to the right side of the heart carrying carbon dioxide. The heart pumps this returning blood to the lungs.
In the lungs the carbon dioxide is removed from the blood and breathed out. The carbon dioxide is replaced with oxygen and returned to the left side of the heart to be pumped around the body again.
The major functions of the ear are to help us to maintain the balance and to aid in hearing capabilities.The ear has three main sections:
The outer ear is the pinna, and its function is to gather the sound waves like a funnel and transmit to the middle ear through the ear canal.
The ear drum covers the other end of the canal.
The sound waves that strike the ear drum setup a vibration. This vibration then travels to the three small bones (ossicles) of the middle ear, (the malleus, stapes and incus). The bones of the middle ear move and strike the oval window. The vestibular window separates the middle ear from the inner ear.
The inner ear is also called the cochlea, which is a dual membrane, delicate in structure, with fluid between the membranes and lined with hair cells. The movement of the hair cells that line cochlea, in response to the sound waves, sends electrical impulses to the brain which interprets the sounds we hear.
We say that a verb has ‘persons’. The ‘person’ of the verb depends upon whom or what is its subject and whether the subject is singular or plural.
The issue of ‘person’ is also important when it comes to writing as it enables us to write from a particular point of view. There are three ‘persons’ and each ‘person’ has a singular and a plural option depending upon the subject of the verb…
1st person – this always includes the speaker/writer as the subject of the verb. If the speaker/writer is alone then this would be first person singular and the pronoun used would be ‘I’. If the speaker is included in a group then this would be first person plural and the pronoun would be ‘we’.