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

Synoptic Biology Essay - "The transport of oxygen from air in the alveoli of the lungs to the cytoplasm of respiring muscle cell".

Extracts from this document...


Synoptic Biology Essay "The transport of oxygen from air in the alveoli of the lungs to the cytoplasm of respiring muscle cell". (25) Oxygen is required all of the time for living cells to survive. Oxygen is inspired air is around 20%, in alveolar it is 13% and in expired air it is around 15%. Air is inspired by the vacuum effect of the thorax. The intercostals muscles contract pushing the ribs outwards and upwards, the diaphragm contracts and flattens. This increases the volume in the thoracic cavity and therefore the pressure decreases. This forces air into the lungs through the mouth. The lungs are a pair of gas exchange organs found in air-breathing vertebrates. The lungs are composed of air ducts (the trachea, bronchi and bronchioles) and alveoli, which provide a very large surface area for gas exchange with the blood. The lung capacity (total volume of air in the lungs) of an average adult male is about five litres or 5000cm3. The mammalian trachea is a tube, which links the mouth and nose to the lungs in air-breathing vertebrates. ...read more.


cell thick), and by maintaining a large concentration difference (blood always moves oxygenated blood away from lungs, and partial pressure of oxygen in alveoli is always greater than in capillaries due to breathing). At the capillaries oxygen is diffused into the blood. Blood is a suspension of cells in solution that acts as a transport medium within an animal. In humans, blood consists of about 55% by volume of plasma and 45% by volume of cells. The cells consist of red blood cells (erythrocytes), white blood cells (leucocytes) and small cell-fragments called platelets (thrombocytes). Blood has a number of important biological functions; the one in question is transport. Nutrients, such as glucose and amino acids; respiratory gases (oxygen and carbon dioxide); excretory products, such as urea; hormones, such as insulin; and heat from vasodilation/constriction are all transported in the blood. In the blood the oxygen is transported by red blood cells (erythrocytes) by an iron-containing protein called haemoglobin. Haemoglobin has a quaternary structure consisting of four polypeptide chains, each linked to a haem group. ...read more.


When the blood reaches the respiring muscles oxygen is given from oxyhaemoglobin to myoglobin. Myoglobin is an iron-containing protein found in muscle. Myoglobin consists of a polypeptide chain linked to a haem group. Its function is to store oxygen in muscle tissue for use during strenuous exercise. Myoglobin has to obtain its oxygen from haemoglobin in the blood. It therefore has a high affinity for oxygen and its oxygen dissociation curve lies to the left of that of haemoglobin. The myoglobin gives off its oxygen to the respiring cells, more importantly the organelles such as mitochondria that require it for respiration. These are found in the cytoplasm. This is the content of a cell surrounding the nucleus and enclosed by the cell surface membrane. Cytoplasm consists of organelles suspended in jelly-like matrix (cytosol), which contains enzymes and numerous small molecules, such as amino acids and nucleotides. The cytoplasm is metabolically active, being the site of glycolysis and fatty acid synthesis. Glycolysis is the initial stage of respiration where glucose is broken down into pyruvate, and the products are used in the Kreb's cycle and in the electron transport chain to produce more ATP for metabolic reactions. Richard Thomas O'Sullivan 866 1 ...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

Here's what a teacher thought of this essay

3 star(s)

This is a good essay which outlines the transport of oxygen from the alveoli to the cell. It would benefit greatly from the use of diagrams in order to reinforce the main areas. The concluding paragraph is weak and does not sum up the previous text. 3 Stars.

Marked by teacher Louise Star 09/07/2013

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)

    before they start to respire anaerobically because they have run out of oxygen * The higher the value of VO2 max, the better the heart and blood are at supplying oxygen to the muscles. Heart Disease Heart and circulatory disease is the UK's biggest killer.

  2. Marked by a teacher

    An investigation into the effect of temperature on the rate of respiration in yeast

    4 star(s)

    a larger volume of liquid paraffin to cover the glucose and yeast mixture. Also I could use a thermostatically controlled water bath instead of water in a beaker, because this would keep the temperature of the water bath constant so the temperature of the yeast and glucose mixture would not

  1. Marked by a teacher

    The Advantages And Disadvantages Of Treatments Of Heart Disease.

    3 star(s)

    For safety the implant is insulated. Recovery usually takes 2 days, unfortunately the battery will run out in approximately 10 years and so it will have to be replaced (source 1 & 15). There are two different types of pace maker available the first is fixed rate insensitive, this means that it delivers a constant unchanging

  2. Marked by a teacher

    A-Level Biology Revision Notes

    3 star(s)

    Characteristic features: Low MCV. (under 80 fl). 2. Mechanisms of TIA: * Symptoms: Sudden loss of function in one region of the brain. Symptoms reach peak in seconds, lasts for minutes or hours. But stops in under 24 hours. Site of lesion is suggested by the pattern of attack.

  1. Human biology short notes

    * Many vital chemical reactions takes place inside the body * Enzymes are needed to speed up the rate at which the chemical reactions occur * If enzymes are not present or denatured, chemical reactions will occur slowly * For chemical reactions to take place without enzymes high temperatures are

  2. An experiment to investigate the rate of anaerobic respiration of yeast in various respiratory ...

    The tertiary structure and active sit will therefore be altered, so the substrate cannot bind. Extremes of pH can cause denaturation due to acid hydrolysis of the enzyme, making the enzyme inactive; therefore slowing the rate at which respiratory substrate can be broken down, slowing the rate of respiration.

  1. Experiment to compare oxygen and carbon dioxide content of inhaled and exhaled air

    11s 5s Hydrogencarbonate indicator Remains colourless Turns milky 8) Discussion a. Interpret result Results show that inhaled air contains more oxygen but less carbon dioxide than exhaled air. b. Source of error (i) The size of the flame may have different and it may effect the time burning (ii)

  2. To investigate how the heart rate and breathing rate increase with exercise.Scientific KnowledgeAerobic respiration ...

    If it gets below about 35oC, we die of hypothermia. The temperature range over which all our bodily functions work properly is very narrow, and so the control of body temperature must be efficient and precise. It is important that: Heat gained by body = Heat lost by body Much

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