What is a hypothesis? What are the Key features of a good hypothesis? What is a Null Hypothe- sis? What does qualitative data refer to? What
... [Show More] does Quantitative data refer to? An Idea that you can test using practical exper- iments A good Hypothesis must: Be able to be tested scien- tifically Relate one dependent variable to on independent variable States that there is no relationship or causality, for example, no relation between the temperature and the rate of reaction. It refers to the appear- ance or value of some- thing, such as the colour observed or whether the bubbles are produced. It refers to numerical mea- surements made, such as the volumes and times measured. What is SOP? What are some examples of SOPs? What are risk assess- ments? What is a Hazard? What is a risk? The Standard Operating Procedure. This is an established procedure or method used to carry out a routine activity. It ensures consistent results every time. Titration, Handling of chemicals, disposal of waste, qualitative analyti- cal tests, preparing solu- tions It identifies hazards, eval- uates the risks associated with those hazards and it determines ways to elimi- nate or control those risks. When the equipment or substance can cause harm, for example a hot plate or hydrochloric acid The harm that the haz- ard could cause and the chances of it happening, What is the independent variable? What is the Dependent variable? What is the control vari- able? What should a method be? When planning your method what do you need to make sure? The variables you change during an investigation. The variables you are in- vestigating and measure during an investigation. The variables you keep constant during an investi- gation. A step-by-step set of in- structions, Be logically or- dered, allows you to take sensible measurements, and allows you to test your hypothesis. That it will procedure a range of results, reliable results, precise results, and accurate results. The data can be contin- uous such as the age of What are some types of data? What data is normally dis- played on a bar chart? What are bar charts used for? What is the Pattern on the graph? What is the trend on a graph? plant ir number of plants. Some data can be a mixture of numbers and names such as the num- ber of different types of plants found in a garden. Continuous data. You need to make sure its a smooth curve of best fit, and that the curve goes through or near most of the points. They are used for discrete data but can be used to compare different sets of data. The shape of the graph. It is the line that goes up as time goes by but eventual- ly levels off The relationship between factors on the graph or in the table. The full trend is that the volume increases What is the sample size? What is Primary data? What is secondary data? How do you know if the data is anomalous? The number of people sampled in the investi- gation. To be confident in your conclusions you need a large sample size to give strong evidence. This is the data that you have gathered for yourself through the experiments or investigations . The data that you get in books, scientific papers or the internet. You should compare your primary and secondary data to draw a conclusion It doesn't fit into the pat- tern of the other results. It does not lie close to the line of best fit. What can cause the anom- alous data? What is systemic error? What is the random error? What can misreading the observations cause What is the accuracy? What is the reliability? Not following the method correctly. inaccurate mea- suring/recording and im- purities. The error that is built into the method or equipment which you are using. This can be corrected by cali- brating the balance. These errors are quantitative. These are due to not fol- lowing the method correct- ly and can be minimized by repeating results and taking averages. They can cause qualitative errors. How close is the data to the true value? Errors due to the equipment could make the results less. How trustworthy the data is. It is usually ensured by repeating the readings to What is precision? What is an enzyme? What are proteins made up of? What four chemical groups are attached to the central (alpha) carbon? How many different R groups are there? What are amino acids linked together by? How close the repeat read- ings are to each other. It can be improved by using measuring equipment that measure to more decimal places. A protein molecule that acts as a catalyst in a bio- chemical reaction. amino acids A hydrogen atom. A amino acid. A carboxyl group. A variable R group (side chain). There are 20 different R groups which means there are 20 different amino acids. Peptide Bonds. What does a condensa- tion reaction occur be- tween? What is produced in a con- densation reaction? What is a dipeptide formed by? What do three amino acids form? What do many amino acids join to form? What is a polypeptide with more than 50 amino acids called? What is an active site? What is a secondary struc- ture? What are secondary struc- tures held in shape by? Two amino acids. Water. Two amino acids linked by a peptide bond. A tripeptide A polypeptide A protein. The part of an enzyme where the biochemical re- action takes place. Where a polypeptide chains form orderly shapes. Hydrogen bonds between the -NH of one of the pep- What is tertiary structure? What does the tertiary structure give? What are the most com- mon shapes of secondary structures? What does the active site consist of? When an enzyme cat- alyzes a reaction where does it take place? What do enzymes work specifically to? In a biochemical reaction what are substrates con- verted to? a three dimensional shape of a secondary structure It gives the enzyme the shape of its active site. Coiled ±h-elix and folded ²-- pleated sheet A small number of amino acids which form a specific shape because of the pro- teins secondary and ter- tiary structure. It takes places on the ac- tive site of an enzyme. catalyse one type of bio- chemical reaction. They are converted into products. What does the substrate bind to? What shape does the sub- strate have? What happens after the re- action? The active site is a spe- cific shape that only the substrate will fit, What hap- pens to the active site is the temperature goes too high? What is a catalyst? The active site. Only spe- cific substrates will bind to a particular enzymes site. They have a complemen- tary shape to the shape of the active site on the en- zyme. The product is released and the active site is avail- able to catalyse further re- actions. The temperature is too high, the hydrogen bond will break. This means the enzyme changes its shape so the active site loses its shape. The en- zyme is denatured and co no longer act as a catalyst. It is a substance that speeds up a reaction. It can take part in the reac- tion but is left unchanged at the end of the reaction. What is the collision theo- ry? What dos the energy of the collision depend on? What is the activation en- ergy? Why does the enzyme low- ers the activation energy needed? What is the catalytic activ- ity? What is the substrate? For a reaction to occur, the particles must collide and the particles must have enough energy to react. It depends on the speed of the particle and the angle they collide. The minimum energy needed for particles to re- act. The more particles have the required energy to react. There are more successful collisions. And there is a faster reaction. The increase in the rate of a reaction caused by the inclusion of an enzyme. The molecule that is affect- ed by the activation of the enzyme. What does denatured mean? How can enzyme reac- tions be measured? Why must the initial rate of reaction be recorded? What does the enzyme need, in order to work ef- fectively? What happens if the spe- cific conditions are not pre- sent? When the tertiary struc- ture of the enzyme is changed. They can be measured by measuring a decrease in the substance. By mea- suring the increase in the product, this makes is eas- ier because you know the starting measurement for the product will be 0. It needs to be measured because the rate will de- crease as the substrate is used up and its concentra- tion decreases. Specific conditions. The enzyme-catalysed re- action may slow down or might not work at all What is the optimum tem- perature? What happens as the tem- perature increases to the optimum temperature? What happens below the optimum temperature? What happens above the optimum temperature? What do enzymes have? What does pH affect on the active site? Each enzyme has a optimum temperature at which it works fastest. The reaction rate also in- creases. There is less energy which means there is fewer colli- sions and therefore a slow- er reaction. The hydrogen bonds in the enzyme breaks and the enzyme and active site loses its shape and there- fore there is no catalysis An optimum pH The charge. If the pH changes then the charges on the active site changes ad the substrate may no longer be able to bind to it The rate of reaction. What happens if the con- centration of the substrate is too high? What happens if the con- centration of the enzyme is too high? What is diffusion? What can diffusion occur across? There will be no more ac- tive sites for them to bind to. Increasing the concen- tration of the substrate will no longer affect the rate of reaction There are too many free available active sites com- pared to the substrate mol- ecules, the rate of reaction no longer increases. Diffusion is the movement of substances from a re- gion of high to low concen- tration. It can occur across a mem- brane. As long as the mol- ecules are small enough to pass through the mem- brane then diffusion will occur What factors affect the rate of diffusion? Size- The larger mole- cules move more slowly then smaller ones, so the rate of diffusion decreas- es. Temperature- A higher temperature increases the energy molecules have and so they move faster, increasing the rate of diffu- sion. Distance through a sub- stance- The greater the distance that the mole- cules must travel through a substance, the slower the rate of diffusion. Surface area- As surface area increases, the area of which molecules cans spread is increased and so he rate of diffusion in- creases. Shape of the surface of which the molecule is dif- fusing- the shape of the What does the kinetic the- ory explain? What is the arrangement of particles in a solid? What is the arrangement of particles in a liquid? What is the arrangement of particles in a gas? What are the properties of solids? What are the properties of liquids? It explains the properties of different states of mat- ter. It also explains diffu- sion They are close together in a regular pattern. They are close together in a random pattern. They are far apart and in a random pattern. They are in a fixed shape and they cannot flow. They cant be compressed or squashed. They take shape of a con- tainer, they flow and move randomly. They cannot be compressed or squashed. They completely fill con- tainer and they can flow What are the properties of gases? Where can diffusion hap- pen within? How do humans improve the growth of crops? How can humans have a negative effect on plant growth? How can humans have an effect of the distribution of plants? What pH doe plants grow best at and move randomly. They can be compressed or squased. A mixture of liquids, a mix- ture of gases, and a mix- ture of liquids and gases. They correct soil pH, opti- mum watering. Correct nu- trients present Trampling. Picking wild- flowers. Removing hedges/tress. Sowing crops means field with only one type of plant. Trampling can cause un- usual or more widespread distribution patterns due to seeds being carried on the bottom of shoes. Between 4.5 and 7.5 It can mean that there is a deficiency in necessary Why is Soil Aeration nec- essary? What forms when there is little aeration? Why is temperature impor- tant in plants? What three things are im- portant for plant growth? Why do plants need light? It is necessary to allow suf- ficient oxygen to get to the plant and for carbon diox- ide to be removed. Toxins form such as hydro- gen sulfide gas. Most plants have a opti- mum temperature they will grow at. The temperature is important for seed ger- mination, seeds need the soil to be within a specif- ic temperature range in or- der for them to germinate. Light, water and minerals. They need light for pho- tosynthesis. Plants in high light intensity are more likely to grow better than those in shade. Plants that are used to low light inten- What happens if there is not enough soil moisture? What are the effects of too little rainfall in plants? What are the effects of too much rainfall in plants? How do plants take up mineral ions? What does random sam- pling mean? When is random sampling used? The rate of photosynthesis decreases. Plants cannot take up necessary miner- als and nutrients. Yellow leaves, dry leaves and ground cracks Yellow leaves, Rotted roots, minerals and nutri- ents washed away and soil erosion. Through their roots It means that each poten- tial sample has the same probability of being select- ed. When the area under the study is large. When it is fairly uniform and when there is limited time. What is the minimum sam- ple size? What Abiotic factors can affect plant population? What is a quadrat? What is a point frame? The minimum sample size is the number of samples at which the number of dif- ferent species found starts to level off The soil type/ moisture/ pH. Topography, for exam- ple steepness of slopes. Temperature. A quadrat is a small area of habitat, which some- times has a grid within it. The frame is placed in the ground and the plants and animals inside are count- ed. It contains a number of pins. Sampling lines are set up across the area to be sampled. Species can be recorded along the whole What is a line transects? What is a belt transcet? What do you need to con- sider when investigating fuels? What is the reaction for combustion of fuels? What is the word equation for combustion? length of the line, this is continuous sampling. Or when species can be recorded at set intervals along the line, this is sys- temic sampling. It is similar to a line tran- sect but it gives informa- tion on the abundance of species. Quadrats are placed at set intervals along the line and num- bers of each species are counted within them How much energy they produce, What pollutants they produce and how a fuel is chosen for specific purposes. It is exothermic, there- fore energy is releases as heat. What is flammability? What is toxicity? What does sulfur dioxide react with to produce acid rain? What does acid rain do? What happens if there is limited oxygen in combus- tion? It is one of the most use- ful properties of fuels as it- show easily they catch fire. This can be a hazard and should be treated like it. Fuels can carry impurities that are toxic. They react with moisture in the air. It erodes limestone build- ings and statues. It acid- ifies lakes and rivers. It kills aquatic plants and an- imals. Incomplete combustion occurs which can pro- duce carbon monoxide and soot. What is the wordequa- tion for incomplete com- bustion? What is carbon monxide? What is the word equation for soot? What units is energy mea- sured in? What is specific heat ca- pacity of water? Converting units Fuel + Oxygen -> carbon monoxide + water (+ Heat energy) It is a poisonous gas and can cause headaches, dizziness, nausea and death. CH4 + O2 -> C =+ 2H2O They can be measured in different units, Mainly joules. When 4.2 joules of energy to raise the temperature of 1g of water by 1 degree c. 1 kilojoule (KJ) = 1000 Joules (J) 1 kilometer (KM) = 1000 Meters (m) 1 Kilogram (KG) = 1000 grams (g) 1 kilocalorie (Kcal) = 1000 calories (cal) How can you investigate the energy in food or fuel? What is the equation for Heat energy? How can energy be calcu- lated? What is a battery in a cir- cuit? What is an ammeter in a circuit? You can investigate the en- ergy in food or fuel by burn- ing the food or fuel under a certain volume of water using a calorimeter. Heat energy (J) = Mass of water (g) X specif- ic heat capacity of water (Jg-1C-1) Heat of combustion (kJ mol-1)= ((heat energy to water (kJ) x relative mole- cuar mass of fuel)) / Mass of fuel burnt (g) Made up of more than one cell. It measures current that flows through a compo- nent in a circuit. It is placed in series with the compo- nent What is a voltmeter in a cirucit? Bulb in a circuit What is a resistor? What is a variable resis- tor? It measures the voltage across a component in a circuit. It is placed in paral- lel with the component It controls the current in a circuit. It is used to change the current in a circuit. It goes in series in the circuit What is a diode? It only allows current to flow one way through a cir- cuit. It is in series in the circuit What is power? What can power refer to? What does the work done equal What is the equation for electrical power? What is the equation for physical power? Power is the rate of doing work? It is the amount of energy consumed per unit of time. It can refer to physical work or electrical power. Work done = The amount of energy supplied or transformed. power = voltage x current. p=VI Power = work done/ time (P=W/t) What is a fuse? A fuse is a component of a circuit that will 'blow' if there is a fault in the circuit [Show Less]