harnessing biology Flashcards
(143 cards)
1
Q
what are plant cell walls made of
A
cellulose
2
Q
do fungi have a cell wall
A
yes
3
Q
what is fungi cell wall made of
A
chitin
4
Q
do protoctists have cell walls
A
some
5
Q
do bacteria have cell walls
A
yes
6
Q
what is bacteria cell wall made of
A
murein
7
Q
carbohydrate store in plants
A
stored as starch/cellulose
8
Q
carbohydrate store in animals
A
stored as glycogen
9
Q
carbohydrate store in fungi
A
stored as glycogen
-> only some of them
10
Q
carbohydrate store in protoctists
A
unlikely to be one
11
Q
carbohydrate store in bacteria
A
stored as glycogen
12
Q
are fungi unicellular or multicellular
A
multicellular but can be unicellular
13
Q
are protoctists unicellular or multicellular
A
both
uni - eg. amoeba
multi - eg. seaweed
14
Q
are bacteria unicellular or multicellular
A
unicellular
15
Q
which kingdoms have nucleus’
A
plant
animal
fungi
protoctists
16
Q
what kingdom doesn’t have a nucleus
A
bacteria
-> loop of DNA instead
17
Q
nutrition in plants
A
photosynthesis
18
Q
nutrition in animals
A
feeding
19
Q
nutrition in fungi
A
saprotrophic
-> released digestive enzymes and absorbs products
20
Q
nutrition in protoctists
A
mixture
21
Q
nutrition in bacteria
A
mixture
22
Q
which kingdoms are eukaryotic
A
plant
animal
fungi
protoctists
23
Q
which kingdom is prokaryotic
A
bacteria
24
Q
eukaryotic:
A
- contain nucleus
- membrane bound
25
prokaryotic:
- no nucleus
-> loop of DNA instead
- no membrane bound organelles
26
structure of bacteria
- no mitochondria
-> no respiration
- tail-like structure called Flagellum
27
virus structure
- wont all look the same
- not classed as living
-> can’t reproduce without a host cell
- no distinguishable structure
28
structure of fungi
- no chloroplasts
- hyphae contain many nuclei
- grow thread-like structures canned hyphae
-> lots of hyphae is a mycelium
29
what does biotechnology mean
using any organism (mainly microbes) to make new products that are useful to humans
30
examples of products made from biotechnology
- medicines (penicillin)
- chemicals (enzymes)
- fuels
31
aerobic respiration word equation
oxygen + glucose -> water + carbon dioxide + ATP
32
anaerobic respiration in yeast word equation
glucose -> ethanol + carbon dioxide + some ATP
33
what happens when yeast cells are deprived of oxygen
they respire anaerobically, breaking sugar down into ethanol and carbon dioxide
34
what colour does hydrogen carbonate indicator turn in increasing CO2 amounts
yellow
35
what colour does hydrogen carbonate indicator turn in decreasing CO2 amounts
purple
36
what colour does hydrogen carbonate indicator turn in atmospheric CO2 level
red
37
what happens when bread is baked in the oven
- gas bubbles expand, giving bread its light texture
- baking kills yeast cells
- ethanol from fermenters evaporates
38
investigating effect of temp on respiration in yeast (CORMMSS)
C - change temperature every 10 degrees from 20 degrees celsius to 90 degrees celsius
O - use the same species of yeast
R - repeat 3x for each temperature and find average
M - measure volume of carbon dioxide produced
M - measure after 5 mins
S - same volume of glucose
S - same volume of yeast
39
role of lactobacillus in yogurt production
- digest milk proteins, and ferment the lactose, which produces lactic acid
- lactic acid makes conditions acid, which prevents unwanted organisms growing
40
anaerobic respiration in animals word equation
glucose -> lactic acid (+ some ATP)
41
example of products made from fermentation and biotechnology
- fermentation of yeast (alcohol and bread)
- action of bacteria on milk (yogurt)
- moulds (cheese)
- action of bacteria on ethanol (ethanoic acid - vinegar)
- penicillin
- enzymes
- fuels
42
how are conditions controlled in a fermenter
- temperature
-> water cooling jacket -> fermentation is exothermic (releases heat to surroundings)
-> temp probes -> monitor temp
-> need to maintain optimum temp for enzymes
- pH
-> need to maintain optimum pH for enzymes
-> pH probes
-> add alkaline if too acidic, and acid if too alkaline
- sterilisation
-> prevent competition with other microorganisms (would produce less product and alter taste of product)
-> steam fermenter before use
-> filters to prevent microorganisms entering in air inlet
- aerator or air inlet
-> provide oxygen for aerobic respiration
- stirring paddles
-> mix the content so evenly distributed -> oxygen, glucose, amino acids, bacteria, etc.
-> keeps everything in suspension
43
limiting factors for plant growth
- carbon dioxide concentration
- temperature
- light intensity
44
what does CO2 conc. graph and light intensity graph look like
increasing gradient, then plateau’s
45
what does temp graph look like
curve up to optimum, then curve back down
46
what is crop yield
total amount of edible crop
47
what do we need to increase crop yield
increasing population, means increasing demand for food
48
why do farmers use greenhouses
can control conditions to maximise yield
49
what are 4 ways to increase rate of photosynthesis (greenhouse)
- add carbon dioxide
- artificial heat
- artificial light
- regular watering
50
how does CO2 increase crop yield
increase rate of photosynthesis - its a reactant
51
how does light increase crop yield
allows more photosynthesis to occur - needed for chemical reaction
52
how does heat increase crop yield
increase rate of metabolic reactions
53
how doe soil ions (eg. nitrates) increase crop yield
extra mineral ions taken up -> increases growth
nitrates - protein
magnesium - chlorophyll
54
how does soil structure increase crop yield
good aeration and drainage helps uptake of mineral ions/water
55
how does soil pH increase crop yield
unsuitable pH reduces uptake of mineral ions
56
how can CO2 be controlled in a greenhouse
- propane burner - produces CO2 waste
- CO2 from fossil fuels burning plant
57
how can light be controlled in a greenhouse
- artificial lighting
- transparent windows
58
how can heat be controlled in a greenhouse
- thermostatically controlled vents
- greenhouse effect
- heaters
59
how can soil ions be controlled in a greenhouse
- add fertilisers
- hydroponic culture
60
how can soil structure be controlled in a greenhouse
- ploughing fields - less compact
- act manure
61
how can soil pH be controlled in a greenhouse
add line (calcium salts) to acidic soil
62
what do polythene tunnels protect crops against
harsh weather conditions, including strong winds, frost, and heavy rain
63
how do plants get minerals
soil -> root hair cells
64
what do plants use nitrates for
- amino acids
- proteins
- chlorophyll
- DNA
65
what do plants use phosphate for
- DNA
- part of cell membranes
66
what do plants use potassium for
- enzymes of respiration and photosynthesis to work
67
what do plants use magnesium for
part of chlorophyll molecule
68
what do plants use iron for
need it to make chlorophyll
69
signs of a deficiency in nitrates in plants
- stunted growth of plant
- older leaves turn yellow
70
signs of a deficiency in phosphate in plants
- poor root growth
- younger leaves turn purple
71
signs of a deficiency in potassium in plants
leaves turn yellow with dead spots
72
signs of a deficiency in magnesium in plants
leaves turn yellow
73
how can farmers replenish the mineral in the soil
- crop rotation
-> alternate crops grown each season/year
- add manure (waste products from farm animals)
-> concentration of minerals is not evenly spread
-> organic
-> cheap
-> eutrophication
- artificial fertilisers
-> known concentrations of minerals
-> expensive
-> not organic
74
how do fertilisers work
- fertilisers provide elements needed by plants to grow well, such as nitrogen, phosphorus and potassium
- they can make crops grow faster and bigger so that yields are increased
- the compounds must be water-soluble so plants can absorb them through their roots
75
what are the two main types of fertilisers
- organic - farm yard manure - faeces of animals mixed with straw
- inorganic - chemical fertiliser, formulated amounts of inorganic compounds
76
advantages of organic fertiliser
- cheaper
- natural
- improve soil structure
- returns some nitrogen back to soil
77
disadvantages of organic fertiliser
- heavy and bulky
- not easy to store
- mineral content varies
- only returns a portion of nitrogen
78
advantages of inorganic fertiliser
- evenly spread
- known concentrations
- store till needed
79
disadvantages of inorganic fertiliser
- expensive
- bad for environment
-> eutrophication
- doesn’t improve soil structure
80
how do legume crops replace nitrates lost
contain nitrogen-fixing bacteria
-> convert nitrogen into ammonium
81
process of eutrophication
1) runoff of fertiliser into nearby rivers/lakes
2) algae growth
3) algae growth means there’s no sunlight to plants underwater, so they die
4) plants dying means they don’t photosynthesise, meaning they don’t release oxygen
5) no oxygen means algae die
6) bacteria decompose the dead algae and use oxygen to respire
7) less oxygen means species underwater die
82
how can pests harm the yield of crops
1) lower amount of crop by reducing growth. can damage leaves and decrease photosynthesis
2) affecting appearance/quality of crop making it unsuitable for sale
83
what type of organism can be a pest
all of them - animals, plants, bacteria, fungi, protoctists
84
what is a pesticide
a chemical that kills pests
85
how can pesticides lead to environmental damage
- persistent -> last for a long time in environment
- kill useful organisms
- bioaccumulation -> build up of toxins in the tissue of organisms
- bio magnification -> concentrated as you move along the food chain
86
87
what would an ideal pesticide be
- control pests effectively
- biodegradable
- no bioaccumulation
- safe to transport, store and apply
- specific
- easy to apply
88
advantages of persticides
- kills particular pests effectively
- increase crop yield
- easy to obtain
- easy to apply
89
disadvantages of persticides
- expensive
- can cause environmental challenges (bioaccumulation + biomagnification)
- not organic -> sold for less
- may also kill useful plants and animals
90
examples of introducing a control species to kill pests
- introducing a natural predator
- introducing a herbivore
- introducing a parasite
- introducing a pathogenic microorganism
- introducing sterile mates
- using pheromones
91
disadvantages of biological control (introducing control species)
- need training and research on how to use
- slower
- specific to only one pest
- could drive out native species and become pests in own right
92
advantages of biological control (introducing control species)
- reduce damage on crops
- organic -> sell for more
- not adding chemicals -> no pollution
- not destroying food chain/web if effective
93
biodiversity definition
measure of the variety of different species in a habitat (encapsulates the species richness and evenness)
94
is biodiversity good
yes
having a high biodiversity means that a habitat is more stable - there is a greater variety of species so if there is a change in conditions then there is less chance the whole population will be affected
95
what method could you use to measure the biodiversity of habitats
- use several quadrants
- use a random number generator to choose randomly
- count the density
- multiply up to find total in large field
96
97
deforestation definition
the clearing of trees (usually on a large scale)
98
negative effects of deforestation
- destruction of habitats - loss of habitat results in a huge loss of biodiversity. often species will become extinct
- global warming - more carbon dioxide (less photosynthesis)
- changes the water cycle, less transpiration - when large groups of trees are grouped together their water is released by transpiration which leads to formation of clouds and results in rainfall nearby. if trees are cut down local areas may become drier due to less rainfall. erratic rainfall patterns could result in a drought.
- flooding - without trees the topsoil will be loose and unstable so easily washed away by rain, increasing risk of flash flooding/land slides
- soil erosion, resulting in leaching
-> no trees and other plants to return minerals to soil when they die
-> no tree roots to hold the soil together - stabilising it
-> rain washes the minerals away (leaching)
-> crops planted in deforested areas rapidly use up minerals from the soil
99
100
pollution definition
releasing harmful substances into the environment in amounts that cause harmful effects and which biological processes cannot easily remove
101
what gases do we pollute the air with
- carbon dioxide
- carbon monoxide
- sulphur dioxide
- nitrogen oxides
- methane
- CFCs (chlorofluorocarbons)
102
sulphur dioxide:
- formed when fossil fuels are burnt (fuels contain sulphur)
- major cause of acid rain
-> sulphur dioxide reacts with oxygen in air and dissolves in rainwater to produce dilute sulphuric acid, leading to acid rain
- some lichens are more tolerant to sulphur dioxide
-> patterns of lichen growth can be used to monitor the level of pollution
-> different lichens are called indicator species (indicate different levels of sulphur dioxide)
103
nitrogen oxides:
- nitrogen and oxygen react under very high temperatures and pressures in an engine burning petrol or diesel
- they form poisonous nitrogen oxide fumes
- contributes to acid rains and causes asthma
104
acid rain:
- rain is naturally acidic due to:
-> volcanic eruptions and lightning
-> carbon dioxide dissolving in the water vapour in clouds
- burning fossil fuels produces sulphur dioxide and nitrogen oxides which form sulphuric acid and nitric acid making rain more acidic than it should be
105
what does acid rain cause
- death of conifer trees
- damage of leaves, buds, flowers and roots of trees/plants
- acidification of soil - root hairs less effective (not optimum pH), leaching of ions into lakes which kills fish
- acidification of lakes directly - death of bacteria, algae, fish, amphibian eggs, resulting in a change to the ecosystem
106
carbon monoxide:
- when substances containing carbon (hydrocarbons) burn in a limited supply of oxygen (incomplete combustion occurs) and carbon monoxide is produced
- exhaust gases contain significant amounts of carbon monoxide
- it is a colourless, odourless, and tasteless gas
107
why is carbon monoxide problematic in humans
- haemoglobin binds more strongly with carbon monoxide than oxygen
- overexposure to carbon monoxide means more haemoglobin binds to it and not enough oxygen can get around the body
- loose consciousness and eventually die from lack of oxygen
108
what are the three main water pollutants
- nitrates from fertilisers
- organic waste
- detergents
109
what major problems does sewage cause
- aerobic bacteria in the water polluted by the sewage use up the dissolved oxygen in the water as they breakdown the organic materials. this reduction in the level of oxygen kills larger animals such as freshwater insects and fish
- untreated sewage contains pathogenic bacteria, which are a danger to human health
110
what happens if untreated sewage inters a river
- the level of oxygen in the water decreases as aerobic bacteria and other microorganisms from the sewage decompose the organic matter
- only species adapted to live in low oxygen levels can survive .eg. anaerobic bacteria
- as water moves away from the outlet, it becomes oxygenated as it mixes with clean water and absorbs oxygen from the air
-> the increase in dissolved oxygen levels allows more clean-water species to survive
111
what is the aim of sewage treatment
to remove solid and suspended organic matter and pathogenic microorganisms
this means water discharged is cleaner
112
what indicator species can be used to monitor the level of pollution by organic material
- bloodworm - heavy organic pollution
- caddis fly larva - some organic pollution
- stonefly lymph nodes - clean water
113
nitrates from fertilisers:
- ions (particularly nitrates) from inorganic fertilisers are very soluble. they are leached from soils and can enter waterways
- levels of nitrates rise rapidly in lakes and rivers. causes eutrophication
- eutrophication is natural but the nitrates cause it to happen at a much faster rate
114
eutrophication:
1) nitrates levels rise, algae reproduce rapidly due to increased protein production
2) algae form an algal bloom
3) the algae prevent light from reaching under the waters surface
4) submerged plants can’t photosynthesise and therefore die, depleting the oxygen
5) the algae also die as they run out of nitrates, depleting the oxygen further
6) bacteria decay the dead plants and algae (releasing more nitrates, so the cycle starts again)
7) the bacteria reproduce (due to the large amounts of dead matter), respiration uses up more and more oxygen
8) the water can become anoxic (no oxygen) so all life dies
115
what influences eutrophication
- more severe in hot weather
-> less water, nitrates more concentrated
-> increased enzyme activity
- less severe in moving water
-> nitrates are rapidly diluted
-> water is continuously re-oxygenated
- organic matter
-> the fungi and bacteria that decompose it use up oxygen in respiration
116
toxic chemicals (pesticides/herbicides):
- sprayed on crops to prevent damage by insects and growth of weeds
- runoff occurs from agricultural land if toxic chemicals are applied in too high concentration, causing them to enter waterways
- these chemicals cannot be broken down by organisms
- they’d an be absorbed by aquatic plants or invertebrates and can build up in tissues of these organisms over time - bioaccumulation
- at each take of these food chain, increasing levels of chemicals build up in organisms which an eventually build up to dangerously toxic levels in top predators, leading to death or failure to breed - biomagnification
117
why has fish farming increased
global demand has increased due to population growth
118
disadvantages of fish farming
- spread of disease faster
- antibiotic resistance
- animals producing waste (pollution) -> eutrophication
- sterile water and pesticides may be needed to control disease
- feeding fish with wild fish
119
advantages of fish farming
- expected quantity of fish
- control of what’s going into fish
- wont have to spend energy on swimming from predators
- food readily available for fish -> can gain more energy for growth
- selective breeding -> can choose characteristics
- split up by size and species -> no competition
- can control conditions -> eg. oxygen and temperature
- controlled water quality
120
what is selective breeding (fish farming)
fish with desirable characteristics chosen to breed
fast growth, docile and disease resistant
121
what is control of reproduction (fish farming)
male and female fish are kept in separate tanks unless the farmer wants them to breed
122
how is diet controlled (fish farming)
fed frequently, ensuring diet is balanced and high in protein
123
how is disease controlled (fish farming)
pesticides
chemical treatment
keep tanks further apart to minimise transfer of disease
124
how is intraspecific predation controlled (fish farming)
competition between individuals of the same species is reduced by keeping fish of different ages in separate tanks
young are separate from adults to avoid them being eaten
125
how is interspecific predation controlled (fish farming)
competition between individuals of different species is reduced by keeping different species of fish in separate tanks
126
how is water quality maintained (fish farming)
remove waste to allow oxygen concentration to be kept constant
constant flow of water through the tank
127
what methods are used to farm large numbers of fish to provide a source of protein
- selective breeding
- control of reproduction
- diet is controlled
- disease control
- control of intraspecific predation
- control of interspecific predation
- maintain water quality
128
selective breeding definition
the process by which humans breed plants or animals with desired characteristics
129
why are animals and plants selectively bred
- increase food yield
- produce a wide range of medicine
- research into spare-part surgery
- research into the actions of drugs
130
in selective breeding, what’s it called when its human choice
artificial selection
131
in selective breeding, what’s it called when its environmental factors
selection pressure
132
how does selective breeding work
1) selection of desired characteristics by humans
2) cross breeding of male and female with desired characteristics
3) selection of offspring showing desired characteristics
4) repeat the process over many generations until allele for desired characteristic increases in frequency
133
why are certain strains of wheat selectively bred together
- increase yield of grain
- shorter and stronger stem
-excellent for processing to make flour and then bread
134
why are crops selectively bred
- give higher yields
- resistant to certain diseases
- resistant to certain insect pest damage
- are hardier - surviving in harsher climates or produce for longer periods of the year
- a better balance of nutrients in crops for consumption
135
why are garden flowers selectively bred
size, shape, colour, fragrance
136
selective breeding in animals
mate a male and female together with desired characteristics
eg. milk production in cows
eg. racing horses - fastest or best endurance
137
artificial insemination in selective breeding
1) bulls with desired characteristics are kept and their semen is obtained
2) the semen is diluted, frozen and stored
3) farmers can buy quantities of this semen to inseminate their cows
4) the semen from one bull can fertilise thousands of cows
138
examples of selective breeding in animals
- dogs - bred out a dogs instinct to kill
- Belgian blues - bred for muscle mass - more meat
- chickens - bred to be bigger - more meat
139
animals have been selected that:
- produce more meat, eggs and milk
- produce more fur or better quality fur
- produce more offspring
- show increased resistance to diseases and parasites
140
disadvantages of selective breeding in animals
- decrease adaptability
- decrease genetic variation -> less able to adapt to change
- recessive diseases will increase in frequency
- traits not always advantageous to animals
141
advantages of selective breeding in animals
- offspring with desired characteristics -> larger, stronger, more muscle mass
- fitter/stronger
- produce h yield of product - milk/eggs
- increased survival in marginal conditions
142
advantages of selective breeding in plants
- increased crop yield
-> more food
-> increased profit
- resistance to diseases/pests
-> no pesticides
- can grow for longer periods of the year and in places they wouldn’t normally grow
143
disadvantages of selective breeding in plants
- decrease in genetic variation
-> less able to adapt to changes in environment
