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Bio Paper 1 - Final Exams - Coggle Diagram
Bio Paper 1 - Final Exams
B1
L1 - Animal and Plant Cells
Animal
:
Nucleus
Cytoplasm
Cell membrane
Ribosomes
Mitochondria
Plant
:
[AoA]
Cell wall
Chloroplasts
Permanent Vacuole
Bacterial = Prokaryotic
Animal + Plant = Eukaryotic
Vacuole: Responsible for holding water and waste substances within the cell.
L3 and L4 - Microscopy
Nano = 10^-9
Magnification = Image = Actual
Resolving power is how easily a microscope can differentiate between two close objects.
Light:
Cheap
Portable
Limited magnification and resolution
Electron:
Greater mag and res
More expensive
Method:
Place slide on stage and attach with clips.
Use coarse focus to bring the lowest objective lens close to the slide.
Use the coarse focus to increase the distance between the lens and slide.
Use the fine focussing dial to bring the specimen into a clear focus.
L2 - Pro and Eukrayotes
Prokaryotes typically contain: Plasmid DNA, Single DNA loops, Ribosomes, Cytoplasm and Flagella
L5 - Specialisation
Sperm:
Flagellum
Acrosome
Mitoch...
Nucleus with half
Nerve: Myelin sheath (speeds up transmission), axon, synapses, dendrites (increase SA)
Muscle: Can contract due to protein fibres, many mitochondria.
Root hair cells: Long protrusions increase SA, no chloroplasts (cannot carry out photosynthesis).
Xylem: Thick walls with lignin (supports), end walls are broken down to form a long tube, no internal structure.
Phloem: Limited cytoplasm with few internal structures, sieve plates (allows for movement), not much cytoplasm so companion cells needed.
L6 - Cell Division
Bacteria multiply through simple cell division (binary fission). Can occur once every 20 mins if temp and nutri is suitable.
Cell cycle with mitosis:
DNA replicates to form 2 copies of each chromosome, cell grows and copies internal structures.
Mitosis: one set of chromosomes is pulled to each end of the cell, the nucleus divides.
Cytoplasm and membrane divide to form 2 identical daughter cells.
[Mitosis takes place when an organism repairs itself, it happens during asexual reproduction]
L7 - Culturing
Method:
[Bacteria can grow in nutrient broth or on an agar gel plate]
Sterilise all equipment: pass inoculating loop through a flame.
Spread bacteria onto dish.
{Place filter paper disks containing antibiotic}
Secure the lid using tape, do not seal it to prevent harmful anaerobic bacteria from developing.
Place agar plate upside down in an incubator, this prevents condensation from dripping onto the culture.
Incubate at 25
L8 - Stem Cells
Embryonic stem cells can differentiate into any type of body cell whilst adult stem cells can only differentiate into certain body cells such as red blood cells, white blood cells and platelets.
Stem cells can be used in bone marrow transplants in which the patients bone marrow is destroyed with radiation. The patient then receives the bone marrow of a donor. The stem cells then divide. Problems include: compatibility issues, virus transmission.
Therapeutic cloning involves an embryo being produced with the same genes as the patient. The process could be used to treat conditions such as diabetes or paralysis.
L9 - Molecule Transport
Urea diffuses out of cells into the blood plasma and is excreted by the kidneys.
Method:
Peel potato and cut out cylinders using the same cork borer.
Cut the cylinders to the same length.
Record the mass of each cylinder.
Place one in distilled water and one in a concentrated solution.
Remove and dab off surface moisture.
Record the new masses.
B2
L1 - Organisation
Tissue: Group of cells that share a similar function and structure.
Organ: Aggregations of tissue that performs a specific function in the body.
Large molecules such as proteins, carbohydrates and lipids cannot diffuse directly into the blood stream.
Digestive process:
Food is chewed in mouth where amylase enzymes are secreted (digesting starch into glucose)
Food passes down the oesophagus into the stomach (enzymes begin to digest proteins and microorganisms may be killed)
Churning turns the food into a fluid (increases SA for enzymes)
Food passes into the small intestine; the pancreas secretes enzymes that begin digestion of lipids and the liver releases bile.
Diffusion or active transport into blood, water is absorbed into bloodstream in large intestine.
L2 - Enzymes
Enzymes catalyse chemical reactions (they remain chemically unchanged). Enzymes have an active site on which the complementary substrate will bind.
Protease - Breaks down proteins into amino acids [Sto, Pan, SmInt]
Amylase - Breaks down starch into glucose [Saliva, Pan]
Lipase - Breaks down lipids into 3 fatty acids and 1 glycerol molecule [Pan, SmInt]
Bile emulsifies lipid molecules (increases SA:V) and neutralises the acid released in the stomach to allow lipase to function there.
L3 - pH on Amylase
Method:
Place one drop of iodine into each well of a spotting tile.
Take 3 test tubes: one with a ncm^3 of amylase solution, one with ncm^3 of starch solution and one with ncm^3 of a buffer solution.
Place all three test tubes in a water bath at 30 degrees.
Mix the three solutions into one test tube and stir; start a stopwatch.
After t seconds, transfer one drop of the solution to the first well of the spotting tile using a stirring rod.
Continue until iodine remains orange.
Record time and repeat with different buffers.
L4 - Food Tests
The test for reducing sugars is the Benedict reagent. This will give a semi quantitative result and will change from blue to brick red if large amounts of reducing sugars are present. Water bath should be used at ~80 degrees.
The test for starch is the iodine test; this solution will turn from orange to blue/black in the presence of starch.
The test of proteins is the biuret test; this reagent will turn from blue to lilac in the presence of proteins.
The test for lipids is the ethanol emulsification test. Ethanol is added to dissolve the substance, water is then added. A colour change from colourless to a white emulsion will be seen if lipids are present.
Another test for lipids is the Sudan III test; a positive result will have a fatty red layer.
L5 - The Heart
The resting heart rare is controlled by the pacemaker cells within the right atrium.
Flow of Blood:
Deoxygenated blood enters the heart through the vena cava (right side of the heart and leaves the heart via the pulmonary artery.
Oxygenated blood enter the heart through the pulmonary vein and exits through the aorta.
The walls of the left ventricle are thicker and more muscular, this is because it must pump all around the body rather than just the lungs.
L6 - Blood Vessels
Capillaries:
Carry both oxygenated blood and deoxygenated blood between arteries and veins.
Walls are one cell thick and permeable (allows for diffusion of gasses).
Blood is under higher pressure here than in veins.
Veins:
Carry blood to the heart at relatively low pressures.
Contain valves.
Thinner walls than arteries and larger lumen.
Arteries:
Carry blood away from the heart.
Walls are thick, muscular and elastic. They carry blood at high pressures.
Contain a small lumen.
L7 - The Blood
Blood plasma carries water, waste substances and antibodies.
L8 - CHD
Caused by a build-up of fatty material within the coronary artery, narrowing the artery and reducing blood flow.
Stents:
Long lasting.
Short recovery time.
Clotting or infection is possible.
Statins:
Reduces blood cholesterol.
Have to be taken regularly.
No surgery.
Side effects possible.
L9 - Cardiovascular Diseases
Biological:
Do not last as long, no anti-clotting drugs needed.
Mechanical:
Clicks, lasts longer, anti-clotting needed.
L10 - Cancer
A malignant tumour is capable of breaking off and travelling through the bloodstream or lymph system to form secondary tumours.
L11 - Plant Tissue and Transpiration
Transpiration is the movement of water and dissolved mineral ions through the xylem from the roots the leaves. Here the water evaporates.
Greater at higher temp.
Greater in windy conditions.
Greater at high light intensity.
Greater at lower humidity.
B3
L1 - Communicable Diseases
Bacterial cells cause harm to the body by releasing toxins and reproducing quickly through binary fission.
Viruses damage the body by living and reproducing inside of our cells.
In plants, pathogens can be spread through contaminated soil/water, airborne spores, vectors and direct contact.
In animals, diseases can be spread through direct contact, droplets in the air and contamination.
The four types of pathogens: viruses, bacteria, protists and fungi.
L4 - Fungal and Protist
Rose Black Spot:
Treated using fungicides.
Spored dispersed by wind / water.
Causes purple/back spots on leaves.
Malaria:
Caused by the plasmodium protist.
Prevented by prohibiting breeding, insect repellent and mosquito nets.
Spread by mosquitoes as a vector.
Causes reoccurring high temperatures and headaches.
Plasmodium Transfer:
Infected person is bitten and protist is then carried by vector.
Healthy person is bitten, the protist enters their bloodstream.
Protist travels to liver and reproduces.
Protist leaves the liver and enters the red blood cells.
Protist feeds on the haemoglobin within blood cells and reproduces.
L2 - Viral Diseases
HIV:
No cure but controlled antiretroviral drugs.
Prevented with contraception.
Spread by sexual contact.
Flu-like symptoms.
Measles:
No treatment.
Prevented with MMR vaccine and covering nose + mouth.
Spread by droplets in the air.
Fever, red-brown rash, sore red eyes.
TMV:
Remove infected plants.
Wash hands and tools thoroughly.
Spread through contaminated sap and vectors.
Lack of chlorophyll, discolouration.
L3 - Bacterial Diseases
Salmonella:
Antibiotics (extreme).
Prevented by preparing food in hygienic conditions, poultry vaccinated.
Spread by ingesting contaminated food.
Causes fever, cramp, abdominal pain, vomiting.
Gonorrhoea:
Antibiotic penicillin (some strains now show immunity).
Prevented through contraception.
Spread through unprotected sexual contact.
Causes thick yellow discharge and pain on urination.
L5 - Human Defence and Vaccines
Primary Defences:
Skin as a chemical and physical barrier.
Mucus.
Stomach acid.
Tears containing enzymes.
Ciliated cells in the trachea.
Secondary Defences:
The immune system:
Antigens on the pathogens surface are identified by white blood cells.
Lymphocytes produce antibodies to group the pathogens + antitoxins
They are then engulfed by phagocytes.
Memory cells made.
Herd immunity shows that vaccinating a large portion of the population reduces the likelihood of unvaccinated individuals from contracting the disease.
L6 - Antibiotics
Bactericidal antibiotics kill bacteria by removing its ability to create a cell wall.
Bacteriostatic antibiotics inhibit the growth of bacteria by interfering with their DNA replication, protein production and metabolic reactions.
L10 - Drug Discovery
Digitalis = Foxglove
Aspirin = Willow
Morphine = Poppy seeds
The thalidomide drug was originally created to help combat morning sickness but it was found that it caused deformities at birth. It is now used to treat cancer.
Pre-clinical - Tissues and cells for toxicity.
Clinical - Efficacy and dosage on healthy volunteers.
L11 - Antibiotic Resistance and MABs
May occur due to over dosage, an incorrect prescription or an uncompleted prescription.
Uses of MABs:
Drug/Pregnancy Tests
Diagnosis of disease
Treating disease
Making MABs:
Weakened pathogen injected into mouse.
Lymphocytes in mouse create specific antibodies.
Lymphocytes are extracted from spleen and fused with tumour cell to form a hybridoma.
Pregnancy Tests:
Urine applied to test.
Mobile antibodies bind with HCG in the reaction zone.
Bind with immobile antibodies in the results zone.
Dye is released.
B4
L12 - Plant diseases
Chlorosis- Mg deficient.
Aphids feed on plants and cause a loss of sap form the phloem. They can be controlled through lacewing (predator).
Mechanical = Thorns, hairs and mimicry.
Physical = Cellulose cell walls, waxy cuticle, bark.
L1 - Aerobic Respiration
Uses of energy in the body:
Muscle contraction.
Maintaining body temp.
Building up larger molecules.
Building up sugars.
Active transport.
Cell division.
Respiration = Exothermic.
Results of Exercise:
Breathing rate increases.
Breathing rate increases.
Volume of blood pumped per heart beat increases.
Heart rate increases.
Glucose stores decrease.
L2 - Anaerobic Respiration
Animals: Glucose --> Lactic Acid
Plants: Glucose --> Carbon dioxide + Ethanol
The amount of oxygen needed to oxidise all the lactic acid produced through anaerobic respiration is known as the oxygen debt.
Oxidation in the liver converts lactic acid back to glucose.
After hard exercise, the body must increase heart rate, breathing rate and breathing depth to oxidise all the remaining lactic acid.
L3 - Metabolism and Photosynthesis
Metabolic Reactions:
Conversion of glucose to starch, glycogen and cellulose.
The formation of lipids and storage as seeds in plants.
Formation of proteins.
Respiration.
Photosynthesis = Endothermic
Water moves into the roots via osmosis, carbon dioxide enters through the stomata.
Uses of glucose:
Storage as insoluble starch.
Used in cellular respiration.
Production of fats/oils.
Production of cellulose.
Production of amino acids (nitrate ions must also be absorbed by soil).
L4 - Rate of Photosynthesis
Factors affecting rate of photosynthesis: light intensity, temperature, CO2 concentration, amount of chlorophyll.
Method:
Place a boiling tube n[1]cm away from an LED light source (do not release much heat).
Fill the boiling tube with sodium hydrogen carbonate solution (releases CO2).
Place a cutting of pondweed in the boiling tube with the cut end at the top.
Leave pondweed to acclimatise.
Start stopwatch and count the num of oxygen bubbles produced in one minute.
Repeat and calculate a mean num of bubbles.
Repeat after incrementing distance.
Inaccuracies: Bubbles may be too fast to count and bubbles are not all the same size. Can instead use upturned measuring cylinder
Oil burners increase both temp and CO2 concentration within a greenhouse
Independent = Distance from source
Dependant = Bubbles produced per min.
Control = Temp, species of plant, sodium hydrogen carbonate concentration.