2.66 Circultaion

1. When blood comes out of the heart-artery
2. blodo goes into the heart-vein
3. The word for lung is polmonary
4. The word for liver is hypatic
5. The word for kidney is reinal.
6. We have the lungs on top and then the heart followed by the liver and the kidney.
7. Blood which is travelling from the right ventricle travels to the lung therefore it's a polmonary artery.
8. The blood returns to the heart through the polmonary veins and enters the left atrium.
9. Blood leaves the left atrium through the aorta and is transported to the body. The aorta branches to the liver. The smaller blood vessel branches out of the aorta known as the hepatic artery.
10. A branch of the aorta also travels to the kidney. The blood vessel is known as the reinal artery. Blood returns to the heart in a blood vessels travelling up from the kidney. Blood flows into the heart through the veena cava.
11. Blood passes from the liver (hepatic vein) through the capillaries and then back into the heart via the vena cava.

2.65b Blood Vessels

1. The artery is carrying high blood pressure whereas the vein is carrying is carrying low blood pressure.
2. The capillary is the site for exchange.
3. The capillary walls are very thin, only one cell thick, easy for diffusion of gases.
4. The wall of the artery is thick and contains muscle. The lumein carries the blood is narrow. The muscle contracts, it maintains the blood pressure all the way to the organ.
5. Veins are collecting blood and returning them to the heart. The walls are thin compared to the artery. Large lumein which has low resistance, blood can flow through easily. They have valves to stop backflow.

2.65a Blood vessels

1. All arteries take blood away from the heart. There blood is under high pressure. Blood is being delivered to another organ through arteries.
2. All veins take blood to the heart. Veins contain low pressured blood. Blood in veins fro an organ.
3. Between the artery and vein, the blood vessels travel through the organ. This is where we have exchange where the contents of the cell is exchanged with the blood's contents.
4. The blood vessels in an organ are called capillary.
5. Substances go into and out of the cell. e.g. carbon dioxide and oxygen. Nothing goes into the vein or the artery, nor does it go out. The place for exchange is the capillary.

2.64 heart output

1. Exercise involves muscle contraction. This muscle contraction requires energy.
2. The energy is produced by increased levels of muscle cells respiration.
3. The muscle cells needs more oxygen suppiled to it.
4. We need to remove more carbon dioxide.
5. By increasing heart rate, we increase blood supply and oxygen. We can remove carbon dioxide.
6. The heart can also be influenced by hormones, such as adrenaline. This is produced in the adrenal glands which is located on top of the kidney.
7. This travels to the heart in the blood stream. Increases the heart rate.
8. The stimulus for the production of adrenaline is fear, anxiousness, danger etc...
9. A faster beating heart sends more oxygen and more glucose.

2.63a Heart Structure

1. If blood is going into the heart, the blood vessel is called a vein. If blood is going out of the heart that kind of blood vessel in called an artery.
2. The technical word for lung is polmonary. We have the polmonary artery which takes the blood from the heart to the lung.
3. The polmonary vein takes the blood from the lung to the heart.
4. The major artery in the body is the aorta which takes blood from the heart to around the body.
5. The major vein in the body is Vena cava.
6. These two are our major blood vessels.
7. The heart has two small chambers: the left atrium and the right atrium.
8. The large chambers are known as the keft and rught ventricles.
9. What separeates the right and lift side of the heart is the septum.
10. The valves on the left side are called the bicuspid valves which open and close, allowing blood to flow through.
11. The valves in the right side are called the tricuspid valves.
12. The valves beneath the aorta and polmonary artery are called the semilunar valves.
13. The bicuspid valves: When the pressure is high above the valves, the blood forces down through the valves, forcing the cusps open. The blood then flows to a region of low pressure. 
14. When the ventricle contracts we get high pressure below the bicuspid/tricuspid valves, causing it to close. This makes a sound 'lub' or 'lup'
15. The semilunar valves react in the same way. When the high pressure is below the valves, the blood is forced upwards into the arteries, opening the cusps. However, when the the heart relaxes the blood flows back down, closing the semi lunar valves. This is the second sound known as 'dub'.
16. This overall, gives a lub dub sound. 'Lub' is the sound caused by the closure of atrial ventricular valves whereas 'dub' is caused by the closure of the semilunar valves.

2.62 Clotting

1. Platelets are produced in bone marrows and they are fragments of cells.
2. When we have a wound, the platelets in the blood would be exposed to the air and therefore they release chemicals.
3. In the blood there is a protein called fibrinogen and this is soluble. However from the chemical in the platelets this turns into firbin.
4. This results in us getting a metrix, a netwrok of fibrin molecules on the wound and onto this solidifies red blood cells. This will dry over to form a scab beneath which the cells will begin to repair the wound.
5. The clotting which occurs right below the wound stops blood loss.
6. White blood cells will attack any pathogens present in the wound or underneath the wound.

2.61 Vaccination

1. In vaccination, the pathogen is dead or wekeaned (attenuated) therefore the pathogen cannot cause disease.
2. However, the pathogen can still be injected into the system and be presented to the lymphocyte.
3. This will resu;t in a plasma clone and a clone of memory cells.
4. The reason we have to vaccinate is because the process of meeting the pathogen and producing the plasma cells and memory cells takes time.
5. During the time, the organism may be killed or damaged severely.
6. Therefore if we inject an attenuated pathogen, it doesn't do any of those things. However, it does produce memory cells and antibodies.  
7. Next time when the person meets the real pathogen, in would be quickly picked up by the memory cells and would be killed to the antibodies.
8. The memory cells would divide to form clones of plasma cells resulting in many antibodies.  
9. This does not give the pathogen to cause death or damage.

260b lymphoytes

1. Pathogen is a disease causing organism e.g. bacteria.
2. Lymphocite is a type of white blood cell. It had a large nucleus.
3. Each bacteria has a specific type of lymphocyte.
4. When the bacteria and the lymphocyte come together, the White blood cell divides into two clones.
5. One clone is called memory cells while the other clone releases antibodies and is known as plasma cell.
6. These plasma cells release from the cell into the bloodstream, protein molecules which are our antibodies.
7. The antibody attaches to the bacterial cell an act as a label that will atract phagocytes or the antibody attatches and causes bacterial lysis, the cell bursts.
8. The antibody causes the bacterial cells to stick together. They cause many bacteria to stick to gether. This is called glutination. This results in a phagocyte engulfing many bacteria at the same time.
9. The chances of the bacteria meeting the memory cells is greater than meeting the one original cell. This results in us reacting faster with more antibodies. This is called the secondary response.

2.60a Phagocytosis

1. White blood cells have lobed nucleus. It defends us against infections. It can detect the bacteria because the bacteria gives off chemicals. Phagocytes is a type of white blood cell.
2. 'phago' means feeding and 'cites' mean cells.
3. When the phagocytes sense the chemicals from the bacteria, they extend themselves around the bacteria. These extensions are called psaedopodia. 'Psaedo' means false and 'podia' means food.
4. Later, on the next stage, the bacteria is enclosed around the phagocytes completely. The cell membrane of the phagocytes surround the bacteria completely.
5. However, when the cell membrane of the same phagocyte touch each other when they're around the becteria completely, it fuses.
6. On the next stage, we have the bacteria in the cell enclosed by membrane. The sturtcure of the membrane and the bacteria is known as vesicle.
7. The next stage is that the white cell will introduce enzymes which will destroy the bacteria.
8. The whit blood cell will then excrete and release the fragments of the bacteria.

2.59 Red Blood Cells

1. if we had a cubic metre of blood we would have 5 x 10 to the 6 Red blood cells which means 5000000 red blood cells.
2. The shape-biconcave disc, this gives us short diffusion distance for oxygen.
3. Structure-There is no nucleus, this gives us more space for haemoglobin, Also their is no mitochindria.
4. These cells respire anaerobically therefore they do not use the oxygen they transport.
5. The presence of haemoglobin makes it easier to carry oxygen. Haemoglobin carry oxygen. Each haemoglobin carries 4 oxygen molecules.

2.58 The Role of Plasma

1. Plasma is 55 percent of blood.
2. It is largely composed of water.
3. The water is a solvent and a fluid
4. Carbon dioxide is carried in the plasma and dissolved in the water in the form of hydrogen carbonate ends and some are dissolved as carbon dioxide directly.
5. Digested food takes the form of amino acids and soluble sugars. these are dissolved in the plasma and be transported to the cells.
6. Uria, waste molecules, are also soluble in water and is transported from the liver to the kidney and dissolved in the plasma of blood.
7. Blood is used for the communication between signalling molecules known as hormones e.g. ADH, inulin and glucagon.
8. Water is very good at carrying heat. It is relevant in order to mantain body temperature as it does well in cooling or warmin the body.

Composition of blood 2.57

1. Let's say we have a sample of blood
2. 45 percent of this is cells and 55 percent of this is plasma
3. The types of cells we have the red blood cells known as erithrocytes and white blood cells in which we have the phagocytes and lymphocytes.
4. The plasma is mainly composed of water.
5. We also have the fragments of dead red blood cells known as platelets. These are the clots you find in your blood.

2.59 Transport systems in multi cellular animals

1. This issue with large organisms is that the surface area to volume ratio is very small.
2. This results in slow diffusion.
3. Let's take an elephant for an example. If there was no circulatory or ventillation system, then the oxygen molecules would have to diffuse up to a meter from the outside of the elephant to the cells which are in the center of the elephant,
4. Diffusion distances are big, resulting in slow diffusion.
5. The diffusion system is slow so respiration isn't possible. The oxygen would not get to the cells fast enough.
6. Elephants have developed transport systems such as the ventillation system and a circulatory system to deliver oxygen directly to the cells.
7. This gives it a short diffusion time.

2.49 Diffusion in unicelular animals

1. Examples of unicellular organisms are: fungi, bacteria, prototista.
2. These organisms have a large surface area: volume ratio.
3. The distance for diffusion is very short therefore it's fast.
4. These organisms can rely on diffusion as the distance for diffusion is very short. This makes it fast.

2.47 biological effects of smoking

1. Cigarettes have tars which can bring about lung cancer.
2. Tars contain polycyclis hydrocarbons. They attack the cells in the lungs and cause cancer.
3. They can also cause long-term bronchitus, this is a damage to the cilia cells of the treachea and the bronchi, inflammation. This also has an excessive mucus production.
4. Cigarettes also contain nicitine. It increases blood pressure.
5. Nicotine causes clotting in the bloodstream and heart damage.
6. They contain carbon monoxide which reduces the supply of oxygen. In a pregnant woman, carbon monoxide can reduce oxygen supply to the growing fetus.

2.46 adaptation of alveoli

1. Gas exchange in the lungs is about oxygen in air going into the bloodstream and about carbon dioxide being exhaled.
2. We're adding oxygen and removing carbon doxide.
3. This process is called diffusion as molecules move from a region of high concentration to low concentration.
4. The process does not require energy.
5. Alveoli are the dead end structures of the bronchioles.
6. Around the alveoli are lots of blood vessels.
7. 80 metres squared of surface area is the first adaptaion.
8. The dense network of blood vessels to carry the oxygen and deliver the carbin dioxide.
9. very thin walls which results in faster diffusion.
10. Inside wall of the alveoli is moist- allows tha gases to dissolve easily, faster diffusion.

2.45b Ventillation

1. Ventillation is the biological term for breathing.
2. Intercostal muscles are the muscles between the ribs.
3. The sternum has the ribs extended to the back bone.
4. There are internal intercoastal muscles which slope forward and the external intercoastal muscles run in the opposite direction.
5. When we inhale, there is a contraction of the external intercostal muscles.
6. This causes the thorax to rise and move outward, which increases the volume of the thorax.
7. This results in, a stretching of lung tissue with volume increase. The pressure decreases and air moves in.
8. When this occurs during exercise.
9. When we exhale the inyerbal intercostal muscles contract. the extrenal intercostal muscles relax.
10. The ribcage moves downward and in.
11. Volume reduces in the thorax.
12. this squeezes the alveoli tissue. This results in a pressure increases, forcing the air to move out.

2.45a Ventillation

1. Ventillation is the biological term for breathing
2. It is associated with gas exchange in the lungs
3. This process is largely under the conrtol of the diaphragm.
4. Alveoli is the site of gas exchange.
5. In the walls of the alveoli there would be protein molecules which are called elastin. They stretch. When we stretch the elastic and release them, they would go back to their original shape and size.
6. The diaphragm forms a dome shape pointing up to the thorax when it is relaxed.
7. When we inhale we have a contraction of the diaphragm, which causes it to shorten and flatten and move down.
8. The diaphragm is a sheet of muscle extending from the front edge of the ribcage to the back edge of the ribcage.
9. This increases the volume of the thorac which increases the volume of the lung. This increases the pressure falling in the alveoli and the space increases. Soon, the pressure decreases and air moves into the thorax.
10. When we exhale, the diaphragm has to be relaxed.
11. The diaphragm will go back to the dome shape if it is relaxed. It moves up because of the elastin.
12. When the diaphragm relaxes the elastin is recoiled.
13. This reduces the volume of the alveoli which increases pressure in the alveoli.
14. This forces the alveoli gas out of the lung.

2.44 structure of the thorax

1. Thorax is the biological word for chest
2. The chest is supported by a cage of bones called the ribs.
3. The ribs extend from the bone from the front called the sternum.
4. The ribs come out of the sternum and attach to the backbone, curving around.
5. There are two sheets of muscles between the ribs. These muscles are called the intercoastal muscles.
6. This is the meat tissue when we eat spare ribs.
7. Air enters through a tube beginning at the back of the throat and mouth and decending down into the lung area of the thorax. This tube is known as the trachea or windpipe.
8. The windpipe has cartilage rings that supports the tracheal tissue and stops it from collapsing.
9. The trachea divides into two. These two divisions are known as the bronchi. These are also supported by cartilage.
10. The right bronchi takes air into the right side of the lung whereas the left trachea takes air into the left side of the lung.
11. The brochis also divide into small tubes known as bronchioles. They are microscopic.
12. The larger bronchiles will also have cartilage support.
13. Due to many little bronchioles, the bronchis take up most of the tissue of the lung.
14. Bronchis end in dead end tubes, where the surface area has slightly increased. These dead end structures are known as alveolis.
15. The alveoli is where the gas exchange between air and blood take place in the lungs.
16. The two gases that are involved in gas exchange are carbon dioxide and oxygen.
17. On the surface surrounding the lung tissue is a membrane. This membrane is called the 'pleural membrane'.
18. The membrane that sits on the surface is known as the 'inner' pleural membrane.
19. Another membrane surrounds the pleural membrane known as the outer pleural membrane
20. The space between the two membranes contains the pleural fluid.
21. The outer pleural membrane is attatched to the ribcage.
22. The inner pleural membrane is attatched to the lung tissue.
23. Between the two membranes we have the pleural fluid which reduces friction as the lungs move during ventilation.

2.10 Effect of pH on the rate of reaction

1. On the y axis we are measuring the rate of reaction and on the x axis we are changing the pH.
2. If it is more alkilin or more acidic the rate gradually decreases.
3. When we complete the graph, we see that the graph is symmetrical.
4. Acidic and alkilin conditions change the shape of the active site which slows the reaction.
5. The optimum pH is not necessarily 7. For instance, the enzyme in the stomach, pepsin has an optimum pH of pH3.

6. An enzyme that has an optimum of pH 7, is salivary amylase

1. Increase in temperature increases the average kinetic energy in particles.
2. If we increase the kinetic energy of particle, we increase the number of collisions therefore we will have more reactions.
3. Enzyme + substrate -------enzyme substrate complex ---------- enzyme + product
4. As we increase the temperature, the kinetic energy of the enzyme and the substrate increase, so that we have more complexes formed and product is formed quickly.
5. We find that we reach a temperature after which the rate of reaction decreases quite dramatically.
6. We have an assymetrical curve on a graph for the effect of the temperature on the rate of enzyme catalysed reaction.

7. The temperature declines because the kinetic energy changes the shape of the active site of the enzyme and therefore it doesn't function to produce product, this is known as denaturing.

2.8b enzyme Reactions

1. Glucose + Oxygen -------- energy + carbon dioxide + water
2. Glucose and oxygen are the substrates whilst carbo dioxide, energy, and water are the products.
3. If we do not have an enzymes to break the glucose molecules we have to add energy. An example of this is combustion.
4. Enzyme is a catylyst which will join with oxygen and glucose to form an activative complex, wekaening the structure without the need for extreme heat or pH conditions.
5. Notice on the graph, the affect of the enzymes are to reduce the energy of activation.
6. We could say that enzymes make the reactions occur 'faster' or 'easily'.

2.8a Enzymes

1. Enzymes are biological catalysts in metabloical reactions
2. The enzyme makes the reaction occur faster and also under moderate conditions.
3. Metabolic reactions are biological reactions taking place in the cell such as building molecules up or breaking molecules down.
4. To explain how enzymes work, we have the lock and key hypothesis.
5. The red structure represents an enzyme and it also has a particular shape. This conveys that it is a protein as all enzymes are made of protein.
6. The part labelled b is called the active site.
7. This is the part into which the substrate fits.
8. When the substrate does that it forms and activated complex. When it does this, the enzyme is able to weaken the substrate.
9. The substrate is then broken down, split into the product.
10. The enzyme however remains unchanged in this reaction.

2.7 test for starch and glucose

1. White glucose powder is added to water.
2. Benedicts solution (blue) is then added to the solution.
3. The testube is then into a water bath which should be round about 60-70 centigrades.
4. After 2-3 minutes we would see a colour change from blue to an orange.
5. In weak solution of glucose the blur colour would change to green.

1. White starch powder is added into a dimple tray.
2. We would then add iodine solution (pottasium iodide).
3. Iodine solution is brown.
4. The colour change witnessed would be from brown to black.

2.6 Biological Molecules

1. Carbohydrates- composed of carbon, hydrogen and oxygen. The simplest carbohydrates are sugars.
2. The large molecules the sugars combone to form are starch (in plants) and glycogen.
3. In animals, the chain of sugar, which is glycogen, is branched out.
4. However, in plants they are just a straight long chain which forms starch.
5. Protein-composed of nitrogen, hydrogen, oxygen and carbons.
6. The simplest forms of proteins are amino acids.
7. The amino acids are joined together to make long chains. It is these chains we call proteins.
8. Lipids- the simplest forms of lipid is glycerol.
9. Lipids have another type of molecules known as fatty acids made of carbon, hydrogen, and oxygen chains.
10. Lipids are formed by joining the two typed of molecules, fatty acids and glycerol.

2.24b Vitamins and Minerals

1. Minerals- Calcium and iron
2. Calcium can be obtained from dairy products such as milk. It results in bone strength. lack of calcium can result in rickets.
3. Iron can be obtained from liver and spinach. It manufactures the haemoglobin, in red blood cells. Lack of iron results in anaemia, lack of haemoglobin. People with anaemia are pale, and they get tired very quickly.
4. Fibre is a plant cell wall. It's the carbohydrate cellulose. We get this from plants in our diets. Lack of fibre would result in constipation. The role of fibre is to mantain peristalsis.
5. Water creates solutions. In those solutions, chemical reactions take place. We can obtain this from drinking it or it may be inside the food we're eating itself. Lack of water results in dehydration.

Vitamin	Function	Deficiency Disease
A	Light sensitive pigments in our eye, sources: liver, fish, and oil	Night blindness
D	Absorb calcium from our diet, sources: sunshine, fats, eggs, fish	Rickets- bending of bones
C	Form connective tissues helps cells to stick to each other  sources: Citrus fruits such as orange	Scurvy-bleeding gums in and around the mouth

2.24a

Carbohydrate

1. When grass is flowered they produce seeds which provide rice and wheat, containing the source of carbohydrate.
2. Rice and wheat are forms of starch and starch is also a form of carbohydrate.
3. The root tuber of the potato is also a form of carbohydrate as they have starch stored in their tubers.
4. Carbohydrate provide us with energy through the process of respiration.

Protein

1. animal protein and fish are a well known source of protein. plants can also provide us with proteins through their beans.
2. Proteins are associated with growth, particularly the growth of muscles.

Lipids

1. Lipids comes from animals like cows and fish (oils) and plants (palm oil, sunflower oil). Oil is a form of lipid as it provides us with fat.
2. Lipids are associated with stored energy and insulation.

2.23 balanced diet

   

1. Let's use a seasaw as an example to balance categories.
2. On one side of the seasaw we have diet which includes the components: Lipids, carbohydrates, minerals, vitamins, protein, water, fibre.
3. On the other side of the seasaw we have lifestyle which consists of the components such as age, activity (are you an active person or not), pregnancy, and gender.
4. The diet has to be set to match the lifestyle of the person. Basically the diet has to be decided according to the age, gender, activeness, and condition of the person, so that the person remains healthy.

Production of Yoghurt 5.7

fermenter 5.8

1. The industrial fermentor is a reaction vessel in which fermentation takes place.
2. It is made out of metal, e.g. copper, steel.
3. Lets take a steel jacket for an example. We will find that there is another steel jacket within the steel jacket.
4. In between the two jackets, we will have water because this is a cooling jacket. Once the fermentation starts, it produces heat. The in-between of the jacket cools the reaction down so that it occurs at optimal conditions.
5. the fermentor will need to be cleaned therefore we have the inlet which allows steam through it.
6. The steam sterilises the tank in between fermentations, so basically after the product is produced, the tank has to be cleaned in order to start the process again.
7. Within the fermentor there's a heating plate to raise the temperature.
8. The combination of the heater and the cooling jacket allows us to control the soptimum conditions for fermentation.
9. Nutrients, the food for the micro-organisms have to be added to the tank so that fermentation can actually occur.
10. We will need to monitor the temperature in the temperature probe. This tells us whether to deploy the heater or the cooling jacket.
11. We will also require a pH probe, which is kept at an optimum rate so that we get more reactions.
12. The reaction is stirred through a motor.
13. This agitates the mixture stopping it from clomping together, spreading the mixture.
14. The idea of the fermentor is to create a reaction center in which we control the optimum growth conditions for the micro organisms.
15. At the end of the reaction the product is drained off through the bottom of the tank, the product would then have to go through a downstream process which involves purification.

5.5 beer production

1. The beer is largely ethanol, an alcohol molecule, which is produced from glucose through anaerobic respiration, sometimes called fermentation respiration, which also produces carbon dioxide
2. The micro organisms that perform anaerobic respiration are known as yeast
3. Yeasts are able to supply enzymes which break down the glucose to form ethanol and carbon dioxide.
4. The additional flavour comes from a plant known as hops which is added to the ethanol in order to flavour it.
5. The glucose comes from starch, starch is converted into maltose and maltose is converted into glucose.
6. Starch is converted into maltose by an enzyme known as amylase whereas maltose is coverted into glucose by an enzyme known as maltase.
7. The starch which is used to form glucose for the beer comes from barley seeds, rice, or wheat.
8. The starch is broken down to amylase through the germination of the seed. This is a process called malting.

Summary:

1. In order to make beer, glucose is needed which comes from starch which is sourced from barley seeds, wheat, or rice.
2. Yeasts are needed to respire anaerobically so that ethanol and carbon dioxide can be formed.
3. Flavour is added to the ethanol by the plants called 'hops'.
4. Starch-a-m-y-l-a-s-e-maltose-m-a-l-t-a-s-e-glucose
5. glucose-y-e-a-s-t-ethanol +carbon dioxide, this process is known as anerobic respiration.

2.36 anaerobic respiration

1. Anerobic respiration= respiration without oxygen.
2. This is also an enzyme reaction
3. It takes place in the cytoplasm only
4. It results in the production of molecule known as lactic acid.
5. Glucose---------Lactic acid +energy (less energy than anaerobic)
6. As lactic acid accumulates, it causes fatigue, known as 'lactic' fatigue.
7. anaerobic respiration in plant works the same way but produces different products such as ethanol, carbon dioxide and energy. Ethanol and carbon dioxide are forms of wastes.
8. In yeast, ethanol and carobin dioxide are involved in fermentation

2.35 Aerobic Respiration

1. Glucose + oxygen -e-n-z-y-m-e-s-energy + carbon dioxide + water
2. Respiration is an enzyme reaction and the stages of this reaction take place in the cytoplasm, and in case of aerobic respiration, in the mitochondria.
3. Carbon dioxide is the waste whilst the energy can be used for growth, sensitivity, and other processes which take place within the cell.
4. Balanced equation for respiration is
   C₆H₁₂O₆ + 6O₂ --> 6CO₂ + 6H₂O + energy.
   

2.34 aerobic and anaerobic respiration

1. aerobic respiration- a cell carrying out this type of respiration will break down food molecules and release energy.
2. To do this it requires enzyme system.
3. Aerobic respiration requires that the cell is provided with oxygen.
4. The cell also excretes Carbon dioxide
5. Anaerobic respiration- the cell would again have to break food molecules to release energy. However, oxygen is not required. Another aspects the differentiates this from aerobic respiration, is that the amount of energy released is considerably less.

Summary:

1. Aerobic requires oxygen whereas anaerobic doesn't. Aerobic also requires a great deal of energy compared to anaerobic.

2.33 respiration

1. The process of respiration results in the release of energy in all living things. The energy is contained in the food molecules and is released by the enzyme systems.
2. This takes place in the cytoplasm. This energy is used in processes such as growth, sensitivity to the changes in the environment, cell division.
3. The process of respiration takes place inside the cell. It is the same in animal cells and plant cells.

2.15c Concentration gradients and cells

1. Scenario a- our cell is surrounded by a 5 % glucose solution.
2. The glucose molecules will move through the cell membrane through diffusion from a high concentrated to a low concentrated region.
3. Scenario b-If we increase the concentration to a 10% glucose solution, then there will be many glucose molecules around the cell.
4. The frequency through which the molecules collide with the cell and enter it is much greater than the frequency in scenario A therefore the rate of diffucion is higher in scenario B because we ahave a greater concentration gradient.

2.15b temperature and diffusion

1. Temperature=the average kinetic energy of the molecules going in and out of the cell
2. If we increase the temperature we also increase the average kinetic energy particles therefore they will be moving more making the chances greater, of the molecules to pass through the cell membrane.
3. This overall increases the number of molecules going into the cell.

2.15a Surface area and diffusion

1. In our cell the volume is measured in 1 unit and the surface area is measured in 2 units.
2. Ratio Surface area : volume= 1:2
3. If we increase the surface area, we keep the volume the same. In order to the do this we have to fold the surface.
4. The increasing of surface area allows more molecules to diffuse into the cell.
5. By increasing the surface area we increase the movement of substances into the cell or out of the cell. 

2.13d Active Transport

1. Active transport- molecules move from a low concentrated gradient to being accumulated in a high concentrated region. But to go against the concentration gradient, energy is needed to be applied.
2. The energy comes from respiration.
3. Cells doing active transport will have a high rate of respiration and they will be building up within the cell a high concentration of a particular molecule.
4. The root hair has a large surface area. They actively transport minerals and salts into the cells. They concentrate these into the cell creating a hig concentration region. This also encourages the uptake of water through osmosis into the cell.

2.13c osmosis in plant cells

1. Osmosis-the movement of water from dilute to concentrated solution.
2. The water moves through the cell membrane in the cell.
3. there are three conditions cinsidered for a plant cell: Hypotonic, isotinic, and hypertonic (see obj 2.13b).
4. Consequences of osmosis for plant cells- when hypotonic, the plant is described as being turgid when the volume of the cell increases.
5. When hypertonic, the cell membrane moves away from the cell wall because the volume has decreased. this creates space for the hypertonic solution to move through. This cindition a plant cell is known as plasmolysis.
6. When isotonic volume is constant because the concentration of the external solution is equal to the concentration of the internal solution.

2.13b osmosis in animal cells

1. Osmosis-movement of water from a dilute solution to a concentrated solution.
2. 3 potential scenarios for an animal cell
3. the animal cell finds itself in a dilute solution- this is known as hypotonic- in this case the water will move into the cell. This causes the volume of the cell to increase. However, the cell cannot handle a volume so large or else the cell membrane will burst. This condition is known as lysis.
4. the animal cell finds itself in a solution where the cytoplasm is equal to external solution- this is known as isotonic. In this case, the amount of water going into the cell is equal to the volume going out of the cell therefore the volume remains constant.
5. The animal cell finds itself in a solution which is more concentrated than the cytoplasm.- this is known as hypertonic.- In this case, the water will leave the cell, to the external solution. The volume will decrease. This causes the cell to shrink. This condition is called crinilation.
6. Human cells are isotonic because the volume within their cells remain constant. This is achieved by an organ called the kidney which is present in multi cellular organisms such as humans.

2.13a diffusion in cells

1. Molecules move in diffusion due to their own kinetic energy.
2. Diffusion occurs in cells when oxygen moves into a respiring cell.
3. In this case, there will be a high concentration of oxygen outside the cell and a low concentration of oxygen in the cell.
4. In the opposite direction, there is a high concentration of carbon dioxide in the cell and a low concentration of carbon dioxide around the cell. In this case, the carbon dioxide will diffuse through the membrane, out of the cell.
5. Diffusion: High concentration to low concentration.

2.12 osmosis, active transport, and diffusion

1. diffusion-molecules moving from a region of high concentration to low concentration. The process is passive because we do not have to add energy. The energy comes from the kinetic energy from the molecules itself.
2. osmosis- Movement of water. Water will move from the dilute solution to the concentrated solution through a membrane.
3. active transport-molecules can be moved from outside the cell to inside the cell where they build up high concentration inside the cell. We have to add energy because thats what makes the process 'active' Molecules are tranported from a low to a high concentrated region. This can also happen in the opposite direction where molecules are transported out of the cell.
4. Three ways throgh which substances move in or out of cells.

2.5 Elements in biological molecules

1. Carbohydrates-Carbon, hydrogen, and oxygen
2. Proteins-Carbon, hydrogen, oxygen, and nitrogen
3. Lipids-carbon, hydrogen, oxygen
4. Although the elements present in lipids and carbohydrates are the same, the structure and formula is very different.
5. Carbohydrate include sugars molecules and the larger molecules such as polysaccherides and starch. 
6.  In protein, the simple molecules are amino acids and the larger molecules are proteins.
7. In the work amino acids and proetins the 'n' comes from the element nitrogen.
8. Lipids are divided into two groups: Fats, associated with animals, and oils, associated with plants.

2.4 plant and animal cells

Animal cells

1. Has the nucleus, cell membrane, cytoplasm
2. Store corbohydrate as the molecule glycogen.

Plant Cells

1. The have additional cells such as the cell wall, vacuole, and chloroplasts
2. Plant cells tend to be more regular in their shape.
3. They tend to store carbohysrates in the form of the molecule starch.

2.3 Cell function

Animal Cell

1. Function of the cell membrane-controls what enters and leaves the cell.
2. The nucleus cotrols the function of a cell.
3. The chemical changes such as respiration take place in the cytoplasm.

Plant Cell

1. The vacuole-store molecules such as amino acids and sugars.
2. Chloroplasts-This is where photosynthesis occurs
3. Cell wall-provides cell with support and protection.
Function of the cell membrane-controls what enters and leaves the cell.
The nucleus cotrols the function of a cell.
The chemical changes such as respiration take place in the cytoplasm.

2.2 cell structure

1. All living things are composed of cells.
2. A cell has a cell membrane, nucleus and cytoplasm
3. Plant cells have additional organelles. They have a cell membrane, nucleus, cytoplasm, vacuole, chloroplasts, and the cell wall.

Plant cell

animal cell

2.1 Organisation Cells

1. Organisms are made up of organelles, cells, tissues, and systems.
2. Organisms are usually interpretted as living things who are of an individual species and are able to produce an offspring by reproducing. These include plants. 
3. Systems are organs and tissues and cells working together.
4. In a plant the systems work together in order for the plant to photosynthesize.
5. Tissues are cells of the same kind and it could be told because the cells that make up the tissue have the same shape. They also carry out the same single function.
6. Phloem in the plant is a tissue, this tranports cell 'saps'
7. xylem is a tissue as well- it transports water and minerals.
8. palisade tissue is the main tissue involved in photosynthesis.
9. Mysophyll tissues allowed gases to move through.
10. Tissues working together would gove us an organ.
11. We also have different types of cells in a multicellular organism.
12. During the develeopment of the organism, the cells specialize. It does this by switching on the genes which cause the change in the shape, giving the cell a particular function. This is called defferentiation.
13. There are parts of a cell that work together to give the cell function. For instance, chloroplasts trap light, and the cell membrane, cytoplasm, cell wall. These parts of a cell are called organelles. They work together to form a cell.
14. A group of cells form a tissue, a group of tissues form an organ, a group of organs form a system and the group of systems form an organism.

4.7 energy efficiency

1.  Of 100 percent of producers only 10 percent make it to the next primary consumer level and only one percent makes it to the secondary level.
2. 100 kJ of grass energy represents the grass eaten by the herbivore.
3. Only 10 kJ of the original 100 kJ will become part of the mouse tissue because the herbivores carry out the process of respiration while hunting for their food, they release energy. Not all of the 100 kJ of energy is available to the herbivore. For instance some herbivores cannot digest cellulose therefore this energy would be lost in the form of feces.
4. 90 percent of the energy from the grass to the herbivore would be lost through respiration and undigested food.
5. The secondary consumer would only be able to gain 1 kJ of energy from the grass by eating the herbivore. The secondary consumer will also lose the energy through feces and respiration.

4.6 Energy and substances in Food Chains

1. The producer, it is converting light energy into chemical energy.
2. This chemical energy is taking the form of organic molecules which include carbohydrates, proteins, and lipids. These molecules are food in the producer to the primary consumer. 
3. These molecules are food to the secondary consumer in the primary consumer. 
4. Finally, these food molecules are the food to the tertiary cnsumer in the secondary consumer.  
5. these molecules are composed of Carbon to hydrogen bonds, carbon to oxygen, carbon to carbon, oxygen to hydrogen, carbon to nitrogen bonds. These bonds represent energy whereas the elements represent substances.
6. The producer, while photosynthesizing, creates these organic molecules, which are the substances and contain energy.
7. Organisms use this to respire and grow.
8. These molecules are passed on along the food chain in the form of each organism in the food chain

4.5b food webs

1. Food webs are larger than food chains.
2. Food webs shows organisms feeding at different trophic levels.
3. In a food web, you can see that organisms can have multiple predators. Predators feeding on multiple preys. This results in the food chains becoming linked.
4. Our producer is grass while our primary consumers consist of the rabbit, the beetle, slugs, and mice.The woodlice would be considered our primary consumer. Our secondary consumer would be the badger. There are various secondary, tertiary and primary consumers in the food web.
5. Some organisms could also be considered secondary and tertiary consumer at the same time.
6. The food web is linked by various food chains.

4.5a Food chains

1. Food chain links together the producer, the primary consumer, secondary consumer, and tertiary consumer.
2. Only one organism is shown per trophic level.
3. An omnivore can possess more two trophic levels.
4. Food chains show the flow of matter and energy.

4.4 Trophic levels

1. Trophic-to feed
2. A carrot plant photsynthesizes.
3. A carrot fly eats the carrot plant therefore the carrotfly is a herbivore.
4. Fly catcher eats the carrotfly which makes it a carnivore.
5. Sparrow eats a flycatcher which makes it a TOP carnivore.
6. However, ecologically, different names exist for these feeding levels.
7. The carrot plant could be called the producers, plants produce their own food through photosynthesis.
8. the carrotfly would be called a 'primary' consumer. Takes the chemical energy from the plant and turns it into its own chemical enrgy.
9. The flycatcher would be called a 'secondary' consumer which changes the chemical energy from one form to another.
10. The sparrow hawk would be known as the tertiary consumer. They eat the secondary consumers and turn the molecules of the secondary consumers into useful molecules of their own.
11. Decomposers, such as fungi, break down all these animals after they die. They break down the molecules from these organisms into nitrates and phosphates.

4.2 quadrates

1. Quadrates our used to estimate the population size.
2. We will be looking at sand dune ecosystem.
3. It's made up of a number of population which forms the community and the habitat.
4. The fence across the sand dunes separate the grazed and the ungrazed side of the land.
5. We could start by counting the number of individual organisms on each area.
6. We can count these through quadrating
7. Quadrating is based on squares. They form squared grids. The sqquares can be made of any material.
8. We could take samples from each area and put it into the grid and then start counting the number of organisms.
9. This can be repeated a number of times in order to estimate the population size.
10. Quadrates are a method of sampling in different locations so that the population could be compared in the two different locations.

4.3 Quadrates sample

1. Our sample has to be random and representative (large).
2. Draw a square with grids on it, which act like the x-y coordinates on a graph.
3. Place our quadrates in the square, according the coordinates such as (3,3).
4. Our quadrates have to be random, generated online or from a table. The use of the random numbers are to indicate the (x,y) coordinates.  
5. If the grid our quadrate has been placed in is 1m by 1m, we can count the number of the same species of organisms such as daisies have grown in the particular grid.
6. The bigger the sample, the better. We should be looking for 10 quadrates. The 10 percent of the actual area would be better.
7. Information can be recorded in a table, quadrate number in one column and the no of daisies in the other.
8. We would now add the number of column with the daisies in it and divide it by the number of quadrates.

4.1 Ecosystems

1. Ecosystems includes aspects such as the community of organisms and habitat. These two aspects are a part of the ecosystem.
2. Habitat contains 'abiotic' factors, which are the non biological factors such as the cycle of daylight/dark, temperature, rainfall, humidity, and the slope of land. These factors are all non biological.
3. The community of organisms is made up through population of different species which interact. The population also consists of the number of individuals in a certain species within our habitat.
4. Ecosystem is simply a community of organisms in a habitat. The communuty is made up of different populations of different species interacting within the habitat.

Net gas exchange 2.40

1. photodynthesis only occurs during the day, however, respiration occurs at all times and in all cells.
2. Also, photossynthesis consists of Carbon dioxide and water to release oxygen and glucose. However, in respiration glucose is broken down in the presence of oxygen.
3. Photosynthesis and respiration work in reverse directions. Equations have reversed arrows. 
4. However the process of photosynthesis and respiration occur at the same time therefore there is a possibilty of them being balanced. 
5. When the use of carbon dioxide and oxygen are balanced, it is called the compensation point. 
6. If light intensity is increased, then the rate of photosynthesis will increase therefore the rate of the production of Oxygen and Carbon Dioxide will increase.
7. The net affect would be the oxygen production. Net oxygen production occurs when there is high light intensity.
8. During the night Net carbon dioxide productions occur through respiration. However, not a lot of Carbon dioxide is produced because the stomatal pores are closed.