Download Assignment 3 Help Sheet

Principles of Anatomy and Physiology 3 Help Sheet
Step 1
Introduce the assignment, what will you be looking at within this assignment, what
constitutes the cardiovascular system and respiratory systems. What are the main
functions of each one of these systems?
Example Answer
The following assignment is about the structure and function of the cardiovascular system and
the respiratory system. The cardiovascular system is made up of three parts:
• Heart
• Blood vessels
• Blood
Your fist is approximately the same size as your heart; it is located behind the sternum and
slightly tilted to the left. The heart is mainly made up of cardiac muscle that is also known as
myocardium. The heart acts as a muscular pump that pumps liquid, which is blood, through the
pipes, which are the blood vessels.
The function of the circulatory system is to transport blood around the body. But not only this,
the blood itself carries numerous other substances which the body requires to function.
The main one being oxygen, carried by a protein called haemoglobin, found inside red blood
cells. White blood cells are also vital in their role of fighting disease and infection. Blood
contains platelets which are essential for clotting the blood, which occurs following an injury to
stop blood loss. Blood also carries waste products, such as carbon dioxide away from muscles
and organs in order to be dispelled by the lungs.
There are three circulatory processes occurring simultaneously within the body. Firstly systemic
circulation carries blood around the body, pulmonary circulation carries blood to the lungs and
coronary circulation provides the heart with its own supply of blood.
Step 2
The Systemic circulation and pulmonary circulation need to be identified now. This
is vital to the whole process of the cardiovascular system. Again you need to describe
the structure, so what other parts of the body are in it, have a diagram and then discuss
the function.
Example Answer
Systemic Circulation
At the start of the circulatory cycle the heart pumps oxygenated blood out of the left ventricle,
through the aorta (the largest artery in the body). The aorta divides into smaller arteries, then
arterioles and finally into microscopic capillaries, found deep within muscles and organs. Here
the oxygen (and other nutrients) passes through the thin capillary walls, into the tissues where
it can be used to produce the energy muscles require to contract.
Step 3
Some of the main functions of the cardiovascular system are Thermoregulation,
vasoconstriction and vasodilation. You need to describe these and then how that will
then affect sports performance.
Example Answer
Thermoregulation is the ability of an organism to keep control of the body temperature.
Different organisms do this in their own way. In this case, the heart controls sweating within the
body. When we work our muscles need more oxygen to therefore the heart needs to beat
faster to supply it. When this happens the muscles become warmer as they are contracting and
retracting faster. Therefore this excess heat needs to be extracted through the body and this is
where sweating occurs. Without this sweating performance would……..
Step 4
You now need to discuss and have a diagram of the Structure and function of the
Heart and each part within the heart to show a thorough understanding.
Example Answer
The heart is a large muscular pump which is made up of thick walls, the heart muscle is called
the myocardium and split into two halves which is separated by the septum. The right-hand
side of the heart is responsible for pumping deoxygenated blood to the lungs while the lefthand side pumps oxygenated blood around the body. Each side of the heart consists of two
connected chambers. Each side will have an atrium and a ventricle, the top chambers (the atria
– plural of atrium) are where the blood collects when it enters the heart. The lower chambers
are called the ventricles and are large pumps that send the blood up to the lungs or around the
body.
Step 5
As the heart pumps blood around the body as one of its main functions you need to
discuss the flow, where does it go? which side does what?
Example Answer
Blood flows through the heart and around the body in one direction. This is maintained due to
special valves placed within the heart and within the blood vessels leading from the heart.
The right hand-side of the heart pumps blood to the lungs and the left-hand side of the heart
pumps blood to the body, because of this the heart is sometimes called a ‘double pump’.
Step 6
To allow you to discuss the flow of blood correctly you now need to have diagrams of
the Blood Vessels as well as describing their structure and function. The blood
vessels are arteries, arterioles, capillaries, venules and veins.
Example Answer
Arteries are the large blood vessels that leave the heart; they have thick muscular walls, which
contract and relax to send blood to all parts of the body. The main artery leaving the heart is
the aorta and it quickly splits up into smaller vessels, which are called the arterioles, arterioles
are the small branches of arteries. Artery walls contain elastic cartilage and smooth muscle,
this flexible wall allows the vessels to expand and contract. This helps to push blood along the
length of the arteries. This action is called peristalsis and is how smooth muscle contracts.
Step 7
Blood carries all of the elements we need to survive; we now need to discuss the
Structure and Function of blood. You need to discuss Red and white blood cells,
plasma and platelets. Again diagrams and explanations of their structure and
functions are needed.
Example Answer
Red Blood Cells
Around 99% of the blood cells in the body are red blood cells or erythrocytes. They are red in
colour due to the presence of a red-coloured protein called haemoglobin. Haemoglobin attracts
a lot of oxygen therefore the role of the red blood cells is to take on and transport oxygen to the
cells. There are many millions of red blood cells in the body; 5 million red blood cells for 1mm
volume of blood.
Step 8
As mentioned in the introduction the Structure of respiratory system will be discussed
in this assignment, again a diagram and then a description of each part of the diagram
and a discussion about there function is needed.
Example Answer
•
•
Air enters the body through the mouth and nose; it then passes through the
pharynx, which is the back of the throat area.
It then enters the larynx this is responsible for……..
Step 9
Now the process of Expiration and inhalation after all it is this which gives us the
oxygen to perform. In this section you need to describe what happens when we are at
rest and when we are performing with our lungs, diaphragm, intercostal muscles and
ribs.
Example Answer
Inhalation
At rest
Inhalation is also called inspiration, what happens is that the nervous system sends an impulse
to the diaphragm and the intercostal muscles. The diaphragm flattens due to this which then
increases the length of the thorax. The contraction elevates the ribs and increases the size of
the thorax further. This increase of size in the chest cavity reduces pressure within it, which
then allows an active process where oxygen moves into the lungs.
Step 10
You now need to discuss the Composition of Air; this will allow the reader to
understand what the respiratory system has to do with the air through diffusion.
Example Answer
The air that is inspired is made up of a mixture of gasses; the air exhaled is different in its
composition of gases.
Oxygen is extracted from the air and replaced by carbon dioxide. However, most of the oxygen
stays in the air and this is why mouth-to-mouth resuscitation works as there is still 17%
available to the casualty.
The air that leaves a person's lungs during exhalation contains 14% oxygen and 4.4% carbon
dioxide.
Atmospheres with oxygen concentrations below 19.5 percent can have adverse physiological
effects, and atmospheres with less than 16 percent oxygen can become life threatening.
Step 11
Now that you have identified all the parts of the respiratory system you now need to
discuss the Function of the respiratory system. To do this look at the following points
and then write about each; energy production, removal of waste products, diffusion to
replace oxygen debt.
Example Answer
The aim of breathing is to get oxygen into the bloodstream where it can be delivered to the
cells of the body. At the cells it enters the mitochondria where it combines with fats and
carbohydrates to produce energy, with carbon dioxide and water produced as waste products.
This energy is used to produce muscular contractions, among other things.
Step 12
As a summary you now need to define a number of phrases under the heading
“Respiratory Volumes”. Define these and then try and state where they fit into sports
performance.
The terms are
* Tidal Volume * Inspiratory Reserve Volume * Expiratory Reserve Volume * Vital
Capacity * Residual Volume * Total Lung Volume * Breathing Rate * Respiratory
Volume
Example Answer
Tidal volume – This is the amount of air breathed in with each breath.
Inspiratory reserve volume – This is the amount of space that is available for air to be inhaled.
The inspiratory volume is the extra air inhaled when you breathe in and stop, and then try to
breathe in more.