Biology Course Work

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- visually, limewater turns milky with carbon dioxide, so this was used to assure there was carbon dioxide present

- when carbon dioxide is dissolved into water, the pH lowers

- this means that carbon dioxide makes water more acidic

2.S.2 - perform a first-hand investigation using the light microscope and prepard slides to gather information to estimate the size of red and white blood cells and draw scaled diagrams of each

- white cells are much larger than red cells

- this is because they need to engulf foreign materials

- red need to fit through small capillaries

- there is also a lot more red than white cells in our bodies

- white:red = 1:1000 to 1:2000

- size- white:red = 2:1

- - describe the main changes in the chemical composition of the blood as it moves around the body and identify tissues in which these changes occur

- inorganic ions (sodium, potassium, calcium etc), concentrations remain stable

- plasma proteins- depends on if proteins are needed

- red blood cells- heart- if more oxygen is needed in certain parts of the body

- white blood cells- if an infection occurs or bacteria becomes present

2.S.3 - analyse information from secondary sources to identify current technologies that allow measurement of oxygen saturation and carbon dioxide concentration in blood and describe and explain the conditions under which these technologies are used

- pulse oximeter- oxygen saturation of haemoglobin, pulse rate and blood flow. Gives no information about carbon dioxide levels

- non-invasive probe with sensor attached to finger/ear lobe measures percentage of haemoglobin that is saturated with oxygen, together with heart rate

- used in intensive care units, anaesthesia, recovery after surgery and during hypoxia

- arterial blood gas analyser- oxygen, carbon dioxide and pH levels of the blood

- invasive technology, which requires a blood sample or an arterial probe to be inserted into artery in wrist, groin or arm

- used in intensive care units, baby care units, labour wards

2.S.4 - analyse information from secondary sources to identify the products extracted from donated blood and discuss the uses of these products

- whole blood- to replace blood after large loss (>20%)

- red blood cells- where oxygen carrying capacity is required to increase (anaemia, severe bleeding)

- white blood cells- low white cell count or when serious infections are present

- plasma- to increase blood volume after transplants or surgery, to increase blood proteins and dissolved minerals for clotting factors

- platelets- help clottingfor severe haemorrhaging and bleeding due to diseases such as leukaemia or haemophilia

- cryoprecipitate- blood clotting factors for severe bleeding, haemophilia etc

- anti-D- prevents haemolytic disease in newborn babies of Rh negative mothers (rhesus disease)

- intagram- boost immune system, reducing susceptibility to infections

- hyper-immune globulins- treats/prevents specific infections (chickenpox, Hep B, tetanus, cytomegalovirus)

2.S.5 - analyse and present information from secondary sources to report on progress in the production of artificial blood and use available evidence to propose resons why such research is needed

- scientific breakthroughs in recent years have led to successful synthesis of certain blood components, however artificial blood is not used as a complete replacement for real blood

- one in 3 people will require the use of donated blood in their life but there aren’t enough people donating

- this means that artificial blood is often required, but the technology to fully replicate and use it safely is not avilable yet

- - outline the need for oxygen in living cells and explain why removal of carbon dioxide from cells is essential

- removal of carbon dioxide is essential as too much carbon dioxide raises the acidity of the blood

- this is an issue as it will cause the enzymes used in our metabolism to denature and the organism will suffer

- oxygen is required in blood for respiration to occur

- this allows our cells to reproduce and repair in our body

- - describe current theories about processes responsible for the movement of materials through plants in xylem and phloem tissue

- xylem pulls water and minerals up the plant, from the roots to the leaves

- this is called transpirational pull

- phloem moves organic material up and down the plant

- - choose equipment or resources to perform a first-hand investigation to gather first-hand data to draw transverse and longitudinal sections of phloem and xylem tissue

- diagrams are in last years study notes

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- - explain why the concentration of water in cells should be maintained within a narrow range for optimal function

- cells require an amount of water to function, providing them with nutrients and removing wastes

- too much water will effectively drown the cell

- too little will dehydrate it, the lack of nutrients and build up of wastes killing it

3.2 - explain why the removal of wastes is essential for continued metabolic activity