• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Exercise Physiology.

Extracts from this document...

Introduction

Exercise Physiology Task 1 With physical activity in sport, exercising can have effects on the cardiovascular system. Certain forms of these are the cardiac cycle, blood pressure, the rate of blood flow, transporting respiratory gases and oxygen dissociation. The cardiovascular system includes: * Heart * Blood vessels The heart is a pump, the purpose of which is to drive the blood into and through the arteries. The right side of the heart pumps blood into the pulmonary circulation, and the left side pumps blood into the systemic circulation. The blood in the right side of the heart does not mix with the blood in the left. The heart is myogenic which means it can contract without receiving nervous stimulation from the central nervous system. There are four main neural sites, which work together, in order to ensure that the four chambers of the heart beat regularly. These sites are: * The sino - atrial node - pacemaker, sets the pace at which the heart beats. Also sends a nervous impulse across the atria and makes them contract at same time. * The atrioventricular node - receives impulse from SAN. ...read more.

Middle

Blood pours into the right and left atria from the great veins; they then contract simultaneously, emptying their contents into the ventricles. Atrial contraction lasts about 0.1 seconds. The ventricles then begin to contract and the atrio - ventricular valves are closed by the rising pressure; the closure of these valves causes the first heart sound, which can be heard through a stethoscope placed over the apex of the heart. Ventricular contraction continues lasting about 0.3 seconds in all. When the pressure in the ventricles is greater than that in the arteries the pulmonary and aortic valves are forced open, and the blood flows into the aorta and pulmonary trunk. As the ventricles relax the pressure in them decreases, the pressure in the great vessels forces the aortic and pulmonary valves to close, causing the second heart sound. This can be heard over the near end of the second right rib. During ventricular contraction the atria are relaxed. Following ventricular contraction the whole heart is relaxed for approximately 0.4 seconds. During this time blood is flowing into both atria and through the open atrio - ventricular valves into the ventricles. ...read more.

Conclusion

Oxygen combines with haemoglobin in oxygen - rich situations, such as in the lungs. Oxygen is released by haemoglobin in places where there is little oxygen, such as in exercising muscle. Myoglobin is haemoglobin like pigment found in muscle fibres, which binds only less oxygen to it compared to haemoglobin. It takes up oxygen from the haemoglobin in the blood and stores oxygen within the muscle itself. Oxygen dissociation curve This is an S shaped curve that represents the ease with which haemoglobin will release oxygen when it is exposed to tissues of different concentrations of oxygen. The curve starts with a steep rise because haemoglobin has a high affinity for oxygen. This means that when there is a small rise in the partial pressure of oxygen, haemoglobin will pick up and bind oxygen to it easily. Thus, in the lungs the blood is rapidly saturated with oxygen. However, only a small drop in the % saturation of haemoglobin. Therefore in exercising muscles, where there is a low partial pressure of oxygen, the haemoglobin will readily unload the oxygen for use by the tissues. Changes in blood carbon dioxide level and hydrogen ion concentration causes shifts in the oxygen dissociation curve. These shifts enhance oxygen release in tissues and increase oxygen uptake in the lungs. This is known as the Bohr effect. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Humans as Organisms section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Humans as Organisms essays

  1. Marked by a teacher

    Biology Revision notes - Human Biology

    5 star(s)

    Type 2 This occurs later in life. May be linked to obesity or pregnancy. Cells don't respond to insulin and/ or not enough insulin is made. A balanced diet - more fibre, less sugar, regular exercise, medicines that help the pancreas produce more insulin may be taken, insulin injections.

  2. Marked by a teacher

    Biology notes

    5 star(s)

    * They suffer pain and discomfort. * They do not live in their natural environment. 12.5 Recycling of waste material Recycling in ecosystems * Living things remove materials from the environment for growth and other processes. * These materials are returned to the environment either in waste materials or when living things die and decay.

  1. Marked by a teacher

    Artificial Cardiac Pacemakers

    5 star(s)

    This doesn't allow any electrical impulse to b e conducted, therefore in many cases; the person's heart does not beat at all.27 This will result in death unless treated immediately. The electrical impulses sent by the pacemaker are sufficient to initiate and sustain the beating of hearts with this condition.

  2. Human biology short notes

    Kidneys and Excretion Formation of Urea * Urea is formed in the liver * From excess amino acids * Amino acids are deaminated * Amino (NH ) group is removed * Forming ammonia * Combined with carbon dioxide * Forming urea which removed by the blood * Glycogen formed is

  1. List the effects of exercise on the cardiovascular system, including the cardiac cycle and ...

    around 0.5 seconds and the systolic phase takes about 0.3 seconds, however it is interesting that when studies have been done on trained athletes, they tend to have a longer diastolic phase of the cardiac cycle. This enables a more complete filling of the heart with blood; this means the

  2. HSC Module-Blueprint of Life

    Made up of sub-units called nucleotides * Each nucleotide is made up of a phosphate, a sugar and a nitrogenous base * The sugar is deoxyribose * The four different bases are adenine, thymine, guanine, and cytosine * Adenine pairs with thymine (A-T)

  1. human physiology

    * Epididymis: Once the sperm is matured they are stored here inside the coiled tube. * Urethra: This is the tube that carries urine towards the exterior. The male urethra is much longer than that of a woman. * Testicles: This produces the male hormone Testosterone and also produces sperm.

  2. The Pick Up

    Massive spiky anomalies gave the ship an even more menacing arachnid-like appearance. The sheer size of the craft was forbidding, rivalling the diameter of Leicester Square in London. Derek managed to pull his gaze from the craft toward Farmer Nixon, who surely must have passed out from the horror floating before them.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work