Common Diseases of the Circulatory System

20 Health Benefits of Thyme Oil

Circulatory System
Anatomy and Dissection of the Fetal Pig. To transport nutrients, gases and waste products around the body 2. All four sounds can be heard in a healthy horse. Millions of people around the world suffer from coughs, cramps and aches due to spasms. Two of these cavities are called atria. So if the heart is not enlarged, the sound is more likely a systolic click.


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There are only a few differences between the circulatory system of an adult pig and a fetal pig, besides from the umbilical arteries and vein. There is a shunt between the wall of the right and left atrium called the foramen ovale.

This allows blood to pass directly from the right to left atrium. There is also the ductus arterius which allows blood from the right atrium to be diverted to the aortic arch. Both of these shunts close a few minutes after birth. The monogastric digestive system of the fetal pig harbors many similarities with many other mammals.

The fetal pig's digestive organs are well developed before birth, although it does not ingest food. These organs include the esophagus , stomach , small and large intestines. Mesenteries serve to connect the organs of the fetal pig together. In order for digestion to occur, the fetal pig would have to ingest food. Instead, it gains much needed nutrition from the mother pig via the umbilical cord.

In the adult pig, food will follow the general flow through the esophagus, which can be located behind the tracheae. From the oral cavity, the esophagus leads to the stomach, small intestine, and large intestine. Other organs developing during fetal pig development such as the gallbladder , pancreas and spleen are all critical in contributing to the overall flow of the digestive system because they contain digestive enzymes that will perform chemical digestion of food.

After food is digested and nutrients are absorbed, the food follows through the large intestine and solid wastes are excreted through the anus. In the fetal pig however, the metabolic wastes are sent back to the mother through the umbilical cord where the mother excretes the wastes. Other remaining wastes remain in the fetal pig until birth. The oral cavity of the fetal pig begins developing before birth. The tongue's taste buds, located in the enlarged papillae, facilitate food handling after birth.

These taste buds develop during fetal development. Adult pigs have up to 15, taste buds, a much larger number than the average human tongue, which has 9, The dental anatomy of the fetal pig shows differences from adult pigs. The fetal pig develops primary teeth which are later replaced with permanent teeth. Some may erupt during fetal stage, which is why some of the fetuses show evidence of teeth. Depending on the age of the fetal pig, it is natural to see eruptions of third incisor and canine in the fetal pig.

Similar to human dental anatomy, the overall dental anatomy of the pig consists of incisors, canines, pre-molars, and molars. Piglets can have 28 teeth total and adult pigs can have 44 teeth total.

The fetal pig's urogenital system is similar to the adult pig's system with the exception of the reproductive organs. The fetal pig urinary tract is relatively developed and easy to locate during dissection.

The kidneys are located behind the abdominal organs and are partially embedded into the dorsal body wall by the spine. The ureters carry the urine to the urinary bladder , the large sack-like organ by the umbilical artery and vein, to the urethra. From there, the urine can be excreted. If the fetal pig is a female, there will be a fleshy protrusion ventral near the anus called the genital papilla. The two sac-like organs attached to the coil-like fallopian tubes are the ovaries.

This system can be difficult to find as it is small as well as extremely dorsal and posterior to the other systems. Male fetal pigs have an urogenital opening located behind the umbilical cord. The swelling behind the hind legs of the fetal pig [23] is the scrotum. The male's internal reproductive system has two scrotal sacs, which depending on the age of the fetal pig may or may not have developed testes.

The vas deferens crosses over the ureter and enters the urethra, which then connects to the penis located just posterior to the skin. From Wikipedia, the free encyclopedia. This is why people with a history of cardiac problems are often prescribed medication to keep their blood thin to minimise the risk of clotting within their blood vessels.

The core temperature range for a healthy adult is considered to be between If the core temperature drops below this range it is known as hypothermia and if it rises above this range it is known as hyperthermia. As temperatures move further into hypo or hyperthermia they become life threatening. Because of this the body works continuously to maintain its core temperature within the healthy range. This process of temperature regulation in known as thermoregulation and the cardiovascular system plays an integral part.

Temperature changes within the body are detected by sensory receptors called thermoreceptors, which in turn relay information about these changes to the hypothalamus in the brain.

When a deviation in temperature is recorded the hypothalamus reacts by initiating certain mechanisms in order to regain a safe temperature range.

There are four sites where these adjustments in temperature can occur, they are: These glands are instructed to secrete sweat onto the surface of the skin when either the blood or skin temperature is detected to be above a normal safe temperature. This allows heat to be lost through evaporation and cools the skin so blood that has been sent to the skin can in turn be cooled. Smooth muscle around arterioles: Increases in temperature result in the smooth muscle in the walls of arterioles being stimulated to relax causing vasodilation increase in diameter of the vessel.

This in turn increases the volume of blood flow to the skin, allowing cooling to occur. We see this is in the adjacent diagram where blood that is normally concentrated around the core organs is shunted to the skin to cool when the body is under heat stress. If however the thermoreceptors detect a cooling of the blood or skin then the hypothalamus reacts by sending a message to the smooth muscle of the arteriole walls causing the arterioles to vasoconstrict reduce their diameter , thus reducing the blood flow to the skin and therefore helping to maintain core body temperature.

When a drop in blood temperature is recorded the hypothalamus can also react by causing skeletal muscles to start shivering. Shivering is actually lots of very fast, small muscular contractions which produce heat to help warm the blood. The hypothalamus may trigger the release of hormones such as thyroxin, adrenalin and noradrenalin in response to drops in blood temperature. These hormones all contribute to increasing the bodies metabolic rate rate at which the body burns fuel and therefore increasing the production of heat.

When the fluid levels in the body do not balance a state of dehydration or hyperhydration can occur, both of which impede normal body function and if left unchecked can become dangerous or even fatal. Dehydration is the excessive loss of body fluid, usually accompanied by an excessive loss of electrolytes. The symptoms of dehydration include; headaches, cramps, dizziness, fainting and raised blood pressure blood becomes thicker as its volume decreases requiring more force to pump it around the body.

Hyperhydration on the other hand results from an excessive intake of water which pushes the normal balance of electrolytes outside of their safe limits. The left atrium contracts to pump blood through the bicuspid mitral valve into the left ventricle. The left ventricle pumps blood through the aortic semilunar valve into the aorta. From the aorta, blood enters into systemic circulation throughout the body tissues until it returns to the heart via the vena cava and the cycle repeats.

The electrocardiogram also known as an EKG or ECG is a non-invasive device that measures and monitors the electrical activity of the heart through the skin. The EKG produces a distinctive waveform in response to the electrical changes taking place within the heart. The first part of the wave, called the P wave, is a small increase in voltage of about 0.

The QRS complex corresponds to the depolarization of the ventricles during ventricular systole. The atria also repolarize during the QRS complex, but have almost no effect on the EKG because they are so much smaller than the ventricles.

The T wave represents the ventricular repolarization during the relaxation phase of the cardiac cycle. Variations in the waveform and distance between the waves of the EKG can be used clinically to diagnose the effects of heart attacks, congenital heart problems, and electrolyte imbalances.

During a normal heartbeat, these sounds repeat in a regular pattern of lubb-dupp-pause. Any additional sounds such as liquid rushing or gurgling indicate a structure problem in the heart. The most likely causes of these extraneous sounds are defects in the atrial or ventricular septum or leakage in the valves.

Cardiac output CO is the volume of blood being pumped by the heart in one minute. The equation used to find cardiac output is: Stroke volume is the amount of blood pumped into the aorta during each ventricular systole, usually measured in milliliters. Heart rate is the number of heartbeats per minute. The average heart can push around 5 to 5.

Heart disease is very common, disrupting the normal function of this important organ and often causing death. Visit our Diseases and Conditions section to learn more about common cardiovascular diseases and how we can prevent them. For information about your personal hereditary risks of a variety of conditions involving the heart such as those arising from hemochromatosis or G6PDD, to name two very common hereditary disorders , learn more about DNA health testing.

Systemic & pulmonary circulation