5abcd- bio. resources Flashcards
5A: what is the theory behind bread production
-fermentation (repiration) of YEAST fungi
- ANAEROBIC RESPIRATION
glucose -> ethanol + c02 + ATP
+ we need the c02 to make the bread rise!!
enzymes in yeast: zymase
what is the process of bread production
- dough: yeast + flour + sugar (glucose) + h20
- kneaded and left somewhere warm (opt temp for enzymes)
- enzymes break down flour into sugars. first using aerobic resp (while o2 still available)
- once conditions anoxic (all o2 used up), yeast uses anaerobic resp, producing ethanol + co2
- dough left to rise (co2 bubbles trapped)
- dough is heated (bakes), to kill yeast (fungus) and to evaporate ethanol.
measuring rate of anaerobic resp practical
1 test tube: yeast + sugar solution
+ oil later (prevents o2 entering, ensuring anaerobic resp ==> fermentation)
another test tube: hydrogen carbonate indicator OR limewater (detects co2 prescence)
more co2 = yellow (should turn)
normal = red
decrease = purple
measyring rate:
1. time taken for indicator to change colour
2. count bubbles prod/vol
control variables:
- temp
- yeastamount
- species of yeast
- ph
- conc of glucose
5A: what is the theory behind yogurt production
uses BACTERIA to milkk
bacteria: Lactbacillus (LB)
FERMENTATION (anaerobic)
–> produces lactic acid (what we want)
what is the process of yogurt production (6 STEPS)
- STERILISATION of equipment, pressurised steam/bleach, kills MOs and prevents competition
- PASTEURISATION, heated and then cooled rapidly to kill active bacteria in milk
(cooled to aboid killing LB and opt temp fro enzymes(
- ADD LB BACTERIA
- INCUBATION at 37C, 6 hours (37 = opt and time to prod lactic acid and fro LB to reproduce)
- FERMENTATION, Lb converts lactose in milk –> lactic acid –> ph decreaes, causing to solidify
- COOLING (thickened)
how are fermentors adapted for optimal growth conditions
- STERILISED by pumping high pressure steam + bleach (kills MOs present, prevents contamination + competition of resources)
- MOTORS + PADDLES, distribute temp, agitate mixture, constant exposure to nutrients & resources
- WATER JACKET used to keep tank temp cool and opt growth for enzymes
- AIR PUMPED IN (aerobic only)
- SPECIAL PH & TEMP PROBES to control conditions automatically
FEATURES OF GREENHOUSES?
- permanent
- $$$
- features such as insulation, temp regulation, ventilation
FEAUTURES OF POLYTUNNELS?
- temporary
- $ + easy installation
- less climate control
WHAT AND HOW ARE OPTIMAL CONDITIONS CONTROLLED WITHIN GREENHOUSES?
- TEMP: heaters, optimum enzyme temp, more ESC formed
- LIGHT: transparent materials, allows, additional lighting for winter months
- HUMIDITY: exact, too high = breeds fungi & bacteria, too low, conc gradient steep and water lost via transpiration, reactant for ps
4.CO2 SUPPLY: burning fuels (temp also increases), co2 release, respiration
why do we need fertilisers?
- decompose dead plants and return minerals to soil
- no decomposers within greenhouses, so soil is mineral deficient
- replace missing minerals w fertilisers and to increase crop yield.
organic fertilisers blurt
- manure + straw
- not 100% efficient (cant control contents of manure)
- safe for env.
inorganic fertilisters blurt
- chemically manufactures (K,P,NO3,NH3)
- bought in bulk and allowed to be spread evenly
- causes eutrophication (env. damadge)
pest definition?
organism that reduces crop yield
issues of pesticides? (chemical)
- pests can beconme resistent to them over time
- reapplying regulary, time + $$$
- damadges other wildlife + food chains
- leaching = eutrophication = killing orgs and reducing BD
biological control (organic farming) blurt
- when another living org is introduced to control pests
- introducing a natural predator
e.gs ladybugs kill greenflies - introducing herbivore to destroy weeds
- introducing a parasite
- introducing sterile mates (no offspring produces, and pest population dies out, GM)
what are the conditions controlled in fish farming?
- PREDATION
INTERSPECIFIC (diff species): nets, to seperate
INTRASPECIFIC (same species): nets, sperated by age + size
- PESTS AND DISEASE
- pesticides
- biological control
- dead fish removed quickly
- ABs added to water - DIET
- regularly, grow as fast as possible
- pellets high in protein, max growth. - WATER QUALITY
- filtered, to remove waste
- pH, temp, O2 levels monitered - BREEDING
- SB, fathering large, healthy fish
- afteer gens, ideal fish population produced (max yield)
what is artificial insemination?
- semen from males collected,
- injected into vagina of female
fertilisation + normal process
(semen chose specifically to impregnate many female cows)
PROCESS OF SB?
- select 2 individuals w desirable features
- breed them tgth (artificial insemination)
- select best offspring from next generation
- breed offspring
- repeat over many genertions
GM process?
- restriction enzymes used to cut specific gene from genome
- using same restriction enzyme, cut out section from vector (plasmid/virus)
- ligase enzymes to insert gene into plasmid, with sticky ends
- recombinant dna formed, placed into bacteria
- bacteria reproduce and dna passed on within population, w desired char.
definition of recombinant dna?
DNA that has been modified by inserting a specific gene from another organism
definition of a transgenic organism?
contains dna from a different organisms
1) cuttings- artificial cloning process in plants
- take a cutting from a place
- place in soil w/ nutrients to grow into a full plant
2) tissue culture, micropropagation, artificial cloning process in plants (8 steps)
- choose plant w desired chars.
- take explants (fell plant cells) from shoorts/roots
- sterilise explants to kill MOs (aseptic conditions, bleach)
- explants placed in petri dish, w nutrient medium (agar jelly), in virto (lab conditions)
- contains growth minerals and hormones
- process repeated until mass growth
- optimum conditions for growth
- transferred to GHs + composte to develop into fill plants, identical to the og. plant
CLONING PROS (planst)
- large yield, quick time
- all year-round, growth
- rare + endangered plants
- sterile conditions
- can be GM to increase pop of plants
CLONING CONS (planst)
- genetically identical, small gene pool, sensitive to disease and env changes
- need to sterilize lab
- vulnerable to pests and other MOs (possible pathogens)
why is plant cloning easier than animal clonibg?
- plants have meristems = stem cells= allows explants to grow into adults, with many differentiated and specialsed cells
animal cloning process
- desired nucleus taken, and fused into an enucleated egg cell
- electric shock, triggers mitosis
- cell division into an embryo
- implanted into uterus of surrgoate mother.
- offspring is identical to clone.
CLONING PROS (animals)
- more efficient (less chance) compared to SB
- used to produce proteins, ABS and treats diseases
CLONING CONCS (animals)
ethics
