biology Flashcards
(97 cards)
1
Q
what is a community
A
is all the living things in an ecosystem
2
Q
what is an ecosystem and an example
A
all the organisms in an area where they interact with each other and is made of living and non living parts . an example include rainforest, tundra, desert, arctic and forest
3
Q
what is a habitat
A
is where an organism lives
4
Q
what is a population
A
the number of individuals of a certain species within an area
5
Q
what is an abiotic factor and examples
A
is non living factors present in an ecosystem. examples include temperature, rainfall, soil, moisture and pH
6
Q
what is a biome
A
is a large region of earth that can distinguished from other biomes, by climate and the particular animal and plant community that it possesses
7
Q
what is a example of a biome
A
forest, tundra, desert and grassland
8
Q
the global distribution of biomes is influenced by what
A
abiotic factors such a temperature and rainfall
9
Q
what does biodiversity mean
A
the variety of plant and animal life in the world or in a particular habitat.
10
Q
what can both abiotic factors and biotic factors affect
A
both abiotic factors and biotic factors affect biodiversity and ecosystems
11
Q
what is a biotic factor
A
factors affecting species that are related to, or are the result of, the activities of living things are called biotic factors
12
Q
an biotic factor includes:
A
competition, predation and disease
13
Q
what is a food chain
A
is a relationship where one organisms feeds on the previous one in the series and in turn provides food for the next one
14
Q
how does the food chain begin
A
begins with a producer which is a green plant that makes food for photosynthesis and gets its energy from the sun
15
Q
what does the arrows indicate in a food chain
A
indicates the direction of energy flow
16
Q
what is a species
A
a group of organisms that can interbreed to produce fertile offspring
17
Q
what is a consumer
A
is an organism that gains its energy by eating other organisms
18
Q
what is a herbivore
A
is an organism that eats plant material only
19
Q
what is a carnivore
A
an organism that eats animal material only
20
Q
what is an omnivore
A
an organism that eats both plant and animal material
21
Q
what is ecology
A
is the study of the living organisms in the natural environment, how they interact with one another and how they interact with their non living environment
22
Q
what is a predator
A
is an organism that preys upon other organism
23
Q
what is prey
A
is an organic that is preyed by another organism
24
Q
what is a food web
A
several food chains joined together which shows the energy flow between organisms
25
what is energy flow
the movement of energy from one organism to the next in a food chain/web
26
how do green plants make their own food
by using light energy from the sun. the light energy is converted into chemical energy by using a green pigment in the leaves called chlorophyll
27
what is the word equation for photosynthesis
light energy
carbon + water ———> glucose + oxygen
raw chlorophyll products
materials
energy source + pigment
which traps it
oxygen isnt required +
diffuses from the cell
28
what can glucose be used for
for energy or can be converted into starch - is a storage carbohydrate and can be broken down to simple sugars
cellulose - is a structural carbohydrate and can build the cell wall
29
photosynthesis is a two stage process. what is the first stage called
the light dependent stage or light reactions stage
30
what can happen during stage one of photosynthesis
it involves using light energy from the sun which split water molecules into hydrogen and oxygen the light energy from the sun is trapped by chlorophyll in the chloroplasts and is converted into chemical energy which is used to generate ATP
31
what is the second stage of photosynthesis
the carbon fixation stage
32
explain stage two of photosynthesis
hydrogen and ATP are passed from the first stage along with carbon dioxide from the air. glucose molecules are then produced by the joining of carbon and hydrogen which is controlled by enzymes
33
what are the limiting factors and what effect these have on plant growth
light intensity - this limits the energy available
carbon dioxide - this is an essential raw material
temperature - this limits the rate at which the enzymes controlling photosynthesis work
by overcoming these limiting factors, faster growth rates can be achieved
34
what is a limiting factor
factors which if it is increase will increase the rate of photosynthesis
35
what is chemical energy
the type of energy stored in glucose
36
what is chlorophyll
a chemical in chloroplasts which trap light energy
37
what is photosynthesis
series of enzyme controlled reactions in which green plants produce glucose from carbon dioxide and water
38
what is carbon fixation
is the second stage of photosynthesis where hydrogen and carbon dioxide produce glucose using energy from ATP
39
what is starch
storage carbohydrate produced from glucose
40
what is oxygen
gas produced by photosynthesis
41
what is a chloroplast
plant cell structure where photosynthesis takes place
42
what are the three fates of glucose from photosynthesis
starch, cellulose and respiration
43
explain nitrogen
all living organisms need nitrogen to make protein. plants absorb nitrogen from the soil in the form of nitrate. animals must eat plant or animal protein in order to option their supply of nitrogen
44
the nitrogen cycle is dependant on the activities of several different types of bacteria. what are they
decomposer bacteria which decomposes dead bodies and nitrogenous waste
nitrifying bacteria
denitrifying bacteria
nitrogen fixing bacteria
45
what is compost
an organic matter that has been decomposed and recycled as a fertiliser
46
what is compost used for
to feed and condition the soil
47
why is it important to let organic matter decompose
to release nutrients such a nitrogen and carbon back into the soil so that they can be used by other living things
48
why compost
its environmentally responsible
alternative to burning
saves money
49
give examples of greens that are suitable to compost
nettles, tea bags, grass cutting, raw vegetable peeling and coffee grounds
50
give examples of browns that can be suitable to compost
carboard
newspapers
wood shaving
saw dust
51
what is the ideal ratio of green to brown compost
is one part green and two parts brown
52
examples of items that should not be composted
meat
fish
cooked foot
cat litter
53
how do you look after compost
passive
let it sit
takes months and months
active
have a proper ratio
keep moist
2-6 weeks
54
what is protein
type of molecule that contains nitrogen
55
what is nitrate
form of nitrogen that can be absorbed from the soil by plants
56
what are decomposers
bacteria and fungi which break down dead animals and plants releasing nutrients into the soil
57
what are root nodules
is the structure in the roots of some plants which contain nitrogen fixing bacteria
58
what are the 3 ways that food yield can be increased
monocultures, intensive agriculture and GM crops
59
name one method of increasing food yield. state what it is, how it can be achieved and advantages and disadvantages
monocultures
a vast cultivated population of one crop plant whose members are genetically identical e.g. wheat and rice
natural organisms are cleared. use of chemicals to control unwanted plants
increased yield, food costs less to produce and buy
reduces biodiversity due to use of chemicals
60
name another way of increasing food yield. what it is, how it can be achieved and the advantages and disadvantages
intensive agriculture
involves growing monocultures and supplying plants with chemical fertilisers
using herbicides and pesticides to control competition and pest species. restricted space for animals
increased yield, food costs less to produce and buy
reduces biodiversity. potential animal welfare questions
61
what is the last way of increasing yield. state what it is, how it can be achieved and the disadvantages and advantages
GM crops
plants are genetically altered to have a useful gene added to their genetic makeup
a useful gene from species is inserted into the cells of a crop plants examples are potato resistant to fungal blight and cucumber resistant to disease causing virus
increase yield and decreased use of chemicals
unknown technology. people are concerned that the genetic material introduced into the crop might escape into related species. could produce undesirable strains such as super weeds resistant to weed killers
62
what are pesticides
are chemicals used to kill plants and animals which reduce crop yield
63
what do plants require
nitrogen (N) phosphorous (P) and potassium (K) as well as magnesium (M) and sulphur (S)
64
what is a fertiliser
a substance that helps plants grow and provides them with nutrients
65
what can happen if the soil is short of nutrients
fertiliser can be added to enrich it with the chemicals the plant needs such as nitrates which will increase the crop yield
66
what are nitrates used for
nitrates are used to produce amino acids which are made into plant proteins. animals consume plants/other animals to obtain amino acids for protein synthesis
67
why do we need fertilisers
if you were to grow a plant and remove it then less nitrate is generated by nitrifying bacteria and the soil becomes less fertile so adding a fertiliser will help fix this
68
what does a stable ecosystem consist of
contains a wide variety of species
can exist for a very long time
is not affected by small changes
69
what are the the non living and living parts describes as in an ecosystem
living part : the entire community of living organisms
the non living part: the physical environment
70
what is predation
is the eating of one organism by another
71
what is disease
disease is something that spreads easily in populations where there are many individuals
72
what is competition
where species may compete for various resources such as food and shelter
73
what is a primary and secondary consumer
a primary consumer is a animal that eats plants or plant based foods
a secondary consumer is animal that eats other animals and relies on the primary consumer for their energy and nutrients
74
what is algal bloom
a rapid growth of algae in lochs after fertiliser leaches into them
75
what is bacteria
microorganisms which decompose dead algae using up oxygen in water
76
what is leaching
washing out nutrients e.g. nitrates from the soil into rivers and lochs
77
what are examples of natural fertilisers
manure and compost
78
what are the two types of fertilisers
natural and artificial fertilisers
79
what are artificial fertilisers made up of and what are some examples
chemicals. an example can be phosphorus sulphur and nitrate fertiliser
80
name the advantages of natural fertilisers
are better for the environment and can be used on organic farms
can be cheaper to obtain
adds humus to the soil which improves the soil structure
81
what are the disadvantages of natural fertilisers
the nutrients ratio is not easy to control, the mixture of nutrients is not controllable
can’t use the same field every year
82
what are the advantages for artificial fertilisers
the nutrients ration is exactly calculated so the nutrients mixture is controllable
farmer can choose one specific to the needs of the field and the crop being grown
can use the same field every year
83
what are the disadvantages for artificial fertilisers
farmer has to purchase every year - can be expensive
less good for the environment
84
summarise what happens in the formation of an algal bloom
fertiliser leaches into a loch
water is rich in minerals nutrients e.g. nitrate
rapid growth of algae (algal bloom)
sunlight is blocked by algal bloom - plants die
dead plants and algae consumed by bacteria
bacteria increases in number and causes oxygen to decrease
a decrease in oxygen causes fish and vertebrates to die
85
what is the nitrogen cycle
the nitrogen cycle realeases the protein in dead organisms and their waste back into the soil to be reused
86
nitrogen cycle diagram
protein is animals and plants
decayed into ammonia compounds by bacteria
converted by bacteria into nitrites then nitrates
nitrates absorbed by plant roots
plants converts nitrates into protein
87
what would happen if soil is low in nitrogen
soil low in nitrogen would mean thsy crops grown on it grow very slowly and have a lower yield
88
what is adaptation
adaptation is a change is structure function or behaviour of a species which will help it survive
89
what are the three types of adaption and what do they include
structural changes include changes to colour body size or shape
behavioural changes include things such a migrating swarming and huddling
functional changes include internal body changes
90
what is mutation
mutation is a random change to genetic material and is the only source of new alleles
91
variation
Variation is the differences between members of a population which make it possible for it to evolve over time
92
what are the factors involved in natural selection
reproduction variation selection pressure and survival of the fittest
93
what is natural selection
is the survival of those organisms best adapted to their environment. those with a favourable characteristic will have a selective advantage and are more likely to survive
94
what is speciation
the process of formation of new species
95
what are the three types of barriers that may separate populations
ecological barrier - caused by differences in temperature humidity or pH
e.g. altitude
geographical barriers
e.g. mountains, rivers, sea, desert
behavioural barrier - even if populations live side by side they may be unable to successfully breed
96
what is neutral mutation
a mutation which gives neither an advantage nor a disadvantage
97
what is isolation
where a population becomes separated
