What is osmosis / Osmosis is the movement of water from an area of high water concentration to an area of low water concentration through a selectively permeable membrane.
Describe glycolysis / Glycolysis is the break down of glucose to pyruvic acid (3Carbon atoms). It occurs in the cytoplasm. 2 molecules of ATP are produced. It occurs even when there is no oxygen present.
Name the two types of respiration and the differences between them. / Aerobic respiration occurs in the presence of oxygen and the pyruvic acid from glycolysis is broken down to Carbon dioxide, water and 36molecules of ATP.
Anaerobic respiration happens in the absence of oxygen. Pyruvic acid is converted to lactic acid (in animals) or alcohol and carbon dioxide (in plants)
What is a limiting factor? / It is a factor which when in short supply prevents the reaction occurring at its maximum rate.
Explain what optimum means in relation to enzymes / Optimum is the condition at which an enzyme is most active.
What happens to an enzyme when it is denatured and under what conditions? / The enzymes active site changes shape so a substrate can no longer fit into it.
What is the equation for photosynthesis / Light energy
Carbon dioxide + water à glucose + oxygen
Name as many break down enzymes as possible / pepsin
Proteinàpeptides
catalase
Hydrogen peroxideàwater and oxygen
amylase
Starchàmaltose
lipase
Fatàfatty acids and glycerol
Describe what happens during photolysis / Water is broken down using light energy to produce ATP, oxygen gas (which is released) and hydrogen (which goes on to the carbon fixation stage).
Describe what happens during carbon fixation / This stage relies on enzymes and carbon dioxide is converted into glucose by the addition of hydrogen. This process requires energy in the form of ATP
What is the importance for diffusion for cells? / So cells can obtain important useful substances required for survival and remove harmful waste products
What types of molecules can diffuse? / Small soluble molecules like carbon dioxide, water oxygen, glucose, urea, salts
Name two product produced by microorganisms and how they are produced / Yogurt produced when bacteria convert lactose sugar in milk to lactic acid which thickens and sours the milk.
Bread produced by yeast fermenting glucose to produce carbon dioxide which makes bread rise.
Alcohol produced by the fermentation of glucose by yeast to produce alcohol.
Biogas produced by the fermentation of waste by bacteria to produce methane gas (a fuel)
Gasohol when alcohol from the fermentation of glucose by yeast is added to petrol
What do antibiotics destroy?
What is resistance? / Bacteria NOT VIRUSES
When the antibiotic does not destroy the bacteria
Describe what happens to a plant cell when placed in hypertonic and hypotonic solution / Hypotonic – water diffuses in = turgid (vacuole swells)
Hypertonic – water diffuses out = plasmolysised/flaccid (cell membrane comes in from wall, vacuole and cytoplasm shrink)
Describe what happens to an animal cell when placed in hypertonic and hypotonic solution / Hypotonic – water diffuses in = bursts
Hypertonic – water diffuses out = shrinks
Name the structure which are found in (i) a plant cells and (ii) an animal cell. / Plant – cell wall
Nucleus
Cytoplasm
Vacuole
Chloroplast
Cell membrane
Animal – cell membrane
Nucleus
cytoplasm
What is the equation of the formation of ATP? / ADP + Pi à ATP
How can plants be encouraged to grow to at their maximum rate( think limiting factors) / Use of extra lighting
Increase temperature
Enrich with carbon dioxide
Ensure constant supply water.
What are the three things which can happen to glucose after it is produced in a leaf cell? / Glucoseà used as energy
à stored as starch
à converted to a structural carbohydrate cellulose