biodiversity extras to remember Flashcards
what is recessive epistasis?
homozygous recessive allele at first locus prevents expression of allele at second
What is dominant epistasis?
when dominant allele of one gene masks expression of allele at second
alpha glucose + alpha glucose=?
maltose
alpha glucose+ fructose=?
sucrose
beta galactose + alpha glucose=?
lactose
describe the structure of insulin (1)
2 polypeptide chains joined by disulphide bridges
describe th estructure of pepsin?(2)
stable in the acidic stomach bc acidic r groups
disulphide + hydrogen bonds
what is end product inhibition?
when the product stays bound to the enzyme
give an example of one metabolic poison and summarise its effects.
when eaten cyanide binds irreversibly to mitochondria, stopping aerobic respiration
give an example of one medicinal drug and summarise its effects.
protease inhibitor prevent replication of viruses in host cells by inhibiting the enzyme that makes viral coats
why do solvents affect the permeability of membranes?
they dissolve lipids, leaving holes in the membrane
what happens in G0? (2)
apoptosis
scenescence
what happens in G1? (4)
cells grow
transciption
organelles duplicate
enzymes for DNA replication
what happens in S phase? (2)
dna replication
rapid bc exposed base pairs susceptible to mutagenic agents
what happens in G2? (1)
Cells grow
proportion of polymorphic gene loci=
no. of polymorphic gene loci/ total number of gene loci
what are the 3 bacterial diseases
tuberculosis
bacterial meningitis
ring rot
what are the 3 viral diseases
HIV/AIDS
influenza
tobacco mosaic virus
what are the 3 fungal diseases
ringworm (cattle)
athletes foot
black sigatoka
what are the 2 protoctista diseases
malaria
blight
what are the examples of direct transmission in animals?
physical contact
faceal/oral
droplet infection
spores/vectors
what is the example of indirect transmission in animals?
vector (e.g. malaria)
describe the transmission of malaria?
mosquito=vector
plasmodium in saliva
bites human
plasmodium passes to blood
what are 3 extra factors that influence transmission of disease
living conditions, climate, social factors
list physical plant defences that limit the spread of a pathogen?
callose deposition- blocks sieve tubes cellulose cell wall lignin thickening waxy cuticles bark stomatal closure
list the chemical plant defences against pathogens
terponoids phenols alkaloids defensins hydrolytic enzymes
necrosis- deliberate cell suicide
list the primary non-specific defences against pathogens?
skin, blood clotting, wound repair inflammation expulsive reflexes mucous membranes
describe the structure of a phagocyte
cytoskeleton to allow flexibility to engulf pathogens
describe the mode of action of a phagocyte
pathogen engulfed by endocytosis
trapped within phagosome
lysosomes containing hydrolytic enzymes fuse with phagosome
digest pathogen
what is the role of cytokines, opsonins, phagosomes and lysosomes.
cytokines- cell signalling molecules
opsonins- bind to pathogen’s antigen allowing phagocytes to bind
describe the specific immune response
macrophage engulfs pathogen + presents anitgen on surface
t-helper detects foreign antigen + releases interlukins (a type of cytokine)
which stimulates b and t cell production- clonal selection= choosing which cells are produces
clonal expansion= mitosis of specific b or t cells
b cells differentiate into plasma or memory
memory provides long term immunity, plasma releases antibodies
either opsonins, aggultanins, or antitoxins
t-killer cells kill infected host cells
t regulator cells end immune response
what are agglutanins?
antibodies sticking pathogens together
what are anti-toxins?
antibodies rendering toxins harmless
what is an autoimmune disease?
immune system attacks body e.g. arthritis, lupus
whats the difference between passive and active immunity?
immune system activated
antibodies passed on through breastfeeding/injection
whats the difference between artificial and natural immuunity?
medicinal intervention
normal life processes
whats conservation in situ?
In natural environment
what are the 3 factors affecting biodiversity?
human pop growth - pollution
agriculture- monoculture no genetic diversity
climate change- animals not adapted
what are the economical aesthetic and ecological reasons to maintain biodiversity?
Ecological- protectng keystone species maintaining genetic resource
• economic including reducing soil depleton (contnuous monoculture)
• aesthetc, including protectng landscapes.
what are 2 example of in situ conservation?
marine conservaton zones and wildlife reserves
what are 3 examples of ex situ conservation
including seed banks, botanic gardens and zoos.
what does CITES do?
regulates species trade
check trade doesnt endanger
less endangered may be traded
what does the countryside stewardship scheme do?
farmers given money to maintain historical sites by building walls and planting trees
what does the rio convention do?
shares biological knowledge about species and conserves biodiversity
what features are used to classify plantae?
autotrophic cellulose cell wall
what features are used to classify prokaryotae?
no nucleus smaller ribosomes
What features are used to classify protoctista?
euakryotic, auto/heterotrophic
what is the equation for the mark and recapture method?
C1 X C2 / C3
whaat are the 3 domains?
archaea
eubacteria
eukaryotae
what are the 5 kingdoms?
plantae prokaryotae protoctista animalia fungi
what are the 2 pieces of evidence that have led to new classification systems such the three domain system?
cytochrome c-all orgs that respire have it, the closer the aa sequence, the more closely related the species
dna- more similar the sequence of bases, more closely related the organism
why are there 3 different domains?
prokaryote was divided into bacteria + archaea bc bacteria are different membrane structure , flagella, different enzymes (rna synth)
in the binomial naming system, how should u present printed text?
Genus upper case
itallics
in the binomial naming system, how should u present written text?
genus upper case
underlined
whats the order of the taxonomic levels?
domain kingdom phylum class order family genus species
define classification
the process of sorting living things into groups
define phylogeny
the study of evolutionary rels between species (using phylogenetic trees)
darwins 4 observations
what were his 3 conclusions
offspring look similar to parents
no 2 individuals are individuals are identical
orgs can produce manny offspringg
natural pops remain stable size
there is a struggle to survive
better adapted individuals survive + pass on their characteristics
overtime chanes may give rise to a new species
what r three pieces of evidence for evolution by natural selection?
fossils
dna
cytochrome c
what are the 6 types of variation
intra specific inter specific continuous discontinuous genetic causes environmental causes
what are the 3 types of adaptation
anatomical
physiological
behavioural
2 species of moles (marsupial + placental)have evolved to have similar characteristics, what are they?
large claws
small eyes
tough nose for protection
describe the process of natural selection
mutation produces new alleles (genetic variation)
those with different alleles respond differently to selection pressures
those with advantageous characteristics survive and reproduce, others die
pass on advantageous characteristics
over generations
what are the 2 implications of evolution for humans?
pesticide resistance in insects
drug resistance in microorganisms
what r the 3 point mutations an what do these mean?
silent- no chane in aa produced
missence- aa changed to another
nonsence- aa codon is replaced by stop codon
what r the 2 indel mutations?
insertion/deletion
e.coli normally respires glucoose , but if glucose is absent, respires lactose. when lactose is present, what 2 enzymes does the lac operon need to produce, and what do they do?
b galactosidase- lactose to b galactse and glucose
lactose permease- mem more permeabe to lactose
what happens to the lac operon in the absence of lactose?
regulator gene expressed + repressor protein synthesized
repressor binds to operator region
so rna pol cant bind
enzymes arent synthesized
what happens to the lac operon in the presence of lactose?
lactose binds to repressor protein
so it can no longer bind to operator region
so rna pol can bind to promotor region
so lac z and y can be transcribed and synth enzymes
whats a homebox sequence?
dna involved in regulation of anatomical development
whats a homeodomain sequence?
sequence of aa formed from homeobox sequence
whats a hox gene?
part of homeobox sequence involved in insuring anatomical structures form in correct locations
how can sexual reproduction lead to genetic variaation?
random fusionn of gametes at fertalisation
meiosis crossing over
m1/m2 independant assortment
describe fred sangers method of sna sequencing.
get fragment of dna (restriction enzymes then heat to break h bonds)
clone it using pcr
put into 4 pots , each with ifferent terminator base with florescent marker
terminators bind at different locations on the fragment preventany more from binding
producing different length fragments
whats the difference between dna probes and microarrays?
probe=short single stranded dna complimentary to section being investigated . labelled using radioactive/flourescent markers
microarray= lots of probes detecting many different genes at same time
how is high thruput sequencing different to sanger method?
read each base as its combined
describe the process of PCR
dna mixed with nucleotides, primers, taq dna pol
mixture heated to break h bonds between bases so 2 single strands
cooled so primers can anneal
taq dna pol can now bind
describe the process of dna profiling
dna obtained
digested with restriction enzymes into fragments which will vary in size between people
seperated by electrophoresis and stained
shorter fragments travel further faster
a banding pattern can be seen and compared
in genetic engineering, what are the 2 processes of obtaining a required gene?
mRNA obtained from cells expressing gene, reverse transcriptase enzyme uses mRNA as template , to form cDNA, add primers and dna polymerase to make it double straned
dna probe locates gene , gene is cut using restriction enzymes
in enetic engineering, what is the process of placing gene into vector
plasmid obtained and mixed with restriction enzmes that cut plasmid meaning it has unpaired neucleotide bases called sticky ends. dna ligase catalyses the annealing of the gene to the sticky ends. forming recombinant dna
in genetic engineering, how do we get a vector (e.g. plasmid) into a recipient cell?
electroporatioin- shock applied disrupting membrane so dna can cross
what are the four issues relating to genetic manipulation>
bt gene inserted into plants so they produce bt toxin which acts as pesticide
gm soy beans are resistant to herbicide
list 4 ways in which genetic modification has been used in animals/plants and list 1 strength of each
- bt gene inserted into plants so they produce bt toxin which acts as pesticide
- gm soy beans are resistant to herbicide
- gm rice contain beta carotene (vitamin A supplement)
- Pharmaceutical proteins can be inserted into animals which can be produced in their milk
state one weakness with GM soy beans
super weeds
state one weakness with pharmaceutical proteins
animal welfare
what is gene therapy
replacement of mutated or non-functioning alleles of a gene
name two types of gene therapy and describe their procedure
- somatic cell gene therapy:
- > Liposomes entered into nose which diffuse through lipid bilayer and are incorporated into dna
- > weakened viruses containing dna are injected into patients which then incorporate dna into host genome
- Germ line gene therapy
- > gene engineered into sperm or egg so resulting offspring will contain allele in all cells
list 7 examples of using microorganisms in biotechnology
Brewing-yeast used anaerobically to convert sugar into ethanol
Baking-when yeast respires it produces CO2 which makes bread rise
Cheese-milk treated by lactobacillus which acidifies milk whcih coagulates it. Enzymes thicken milk further
Yoghurt-milk treated by lactobacillus bacteria that coagulates it.
Penicillin-penecillin fungus used to produce secondary metabolite penicillin using batch culture
Bioremediation-use of microorganisms to remove pollution from water
Insulin-produced from gm E.coli by inserting insulin gene into plasmid using continuous culture
describe the four phases of the growth curve.
lag -cells grow enzymes synth no cell division
log-exponential high metabolic rate and reproduction
stationary-pop stabalises growth slows running out og nutrients toxic waste builds up
death- lots of toxic waste nutrients run out, death exceeds birth, pop size decreases
what phase r the microorganisms kept at in continuous culture?
log
whatphase are the microorgansisms kept at in batch culture and why?
stationary
so u can get secondary metabolites
whhat are the four methods of immobalising enzymes. describe them, and say one reason why each is bad
adsorption-enzyymes bound to surface on bead by ionic bonds, bonds r weak so enzymes sometimes break off
covalent bonding- enzymes bound to surface convalently, cross linkedso not all mems directly attached to surface, cross links can affect active site
entrapment- enzymes trapped in matrix fully active sub + product must be able to diffuse into matrix so must be small
membrane seperation- sub diffuse across semipermeable mem containing enzymes and products diffuse back out. reduces acess to enzymes si reaction is slower
list the 5 industrial uses of immobilised enzymes
glucose isomerase= glulcose to fructose coz its sweeter
penecillin acylase=making semi synthetic penecillin
lactase= lactose to glucose and galactose for lactose free milk
aminoacylase for production of l amino acids for additives
glucoamylase converts dextrins to glucose used in fermentation
define productivity
the rate of production of new biomass by producers
define net primary productivity
the proportion of energy from the sun used in the food chain
gross primary productivity
the rate at whcih plants convert light energy to chemical energy
how to increase secondary productivity
animals given antibiotics to reduce loss of energy to infection
selective breeding use to produce breeds with higher growth rates
limiting movement reduces energy lost through heat
Describe the stages of succession
pioneer community of pioneer species grows on bare ground
erosion of the ground and built up dead pioneer species provide soil for rlarger plants like mosses to grow
these outcompete and replaace the pioneer
int he same way larger plants replace smaller plants until a final stable community is reached- a clinmax community
what is secondary succession?
succession on a previously colonised but disturbed/damaged habitat
what is deflected succession?
when succesion stops or is interfered with, which forms a plageoclimax community
Give one example of succession
pioneer species=prickly sandwart, tolerates salty water, roots adapt to unstable sand
prickly sandwart dies, sand biilds up
marram grass, long roots to access water table, and give stability
dune gets bigger, marram grass dies
haresfootclover, leguminous adds nitrates t soil
list some trates of k strategists
large long life span low eproductive rate slow physical development large body mass
list some trates of r strategists
high reporductive rate quick development young reproductive rate short life span small body mass
define carruying capacity
max pop size that can be maintained over time
define conservation and preservation
conservation= maintenance of biodiversity making it sustainable and taking active measures
preservation=maintenance of habitats/ecosystems in their current/oresent condition by minimising human impact-
define conservation
maintaining biodiversity sustainable using active measures
define preservation
maintenance of ecosystems and habitats in their present condition thus minimising human impact
list 3 threats to biodiversity
abuse of populations for food
habitat disruption
introduced species
list 5 conservation strategies
protected areas (national parks) increase carrying capacity by providing food control predators and poachers vaccinate against disease reduce pollution
Evaluate the three reasons for conservation
Ethical: every species has a value (religious argument.) Economic: many species are used as a food source natural predators can drive out pests increased tourism Social: source of medicinal drugs
Describe how managing small-scale timber production can provide a sustainable supply of resources
Coppicing-cutting tree trunk close to the ground to encourage growth (sustainable as tree is alive) once cut new shoots grow from stems
Pollarding-cut stem higher up to prevent deer eating stems
Woodland management divide wood into sections and only cut one section per year (rotational coppicing)prevents overgrowth which would remove light from smaller plants growing below (protects biodiversity)
Describe how managing large-scale timber production can provide a sustainable supply of resources
cutting down trees would lead to oil erosion and depletion of minerals in the soil
removed trees are replaced
only biggest trees are cut down control pests and pathogens
position trees optimum distance apart
Describe how managing fisheries can provide a sustainable supply of resources
Three principles:
- avoid overfishing
- manage fishing and maintain diversity of the ecosystem i.e. no permanent damage
- fishery must adapt to changes in regulations
Describe how managing aquaculture can provide a sustainable supply of resources
growing fish in farms for food to avoid damage to ocean ecosystems
Describe the management of environmental resources and the effects of human activities in the Masai Mara-kenya
high poverty with large wildlife population allowing for tourism
conservation maintains biodiversity while helping local people financially
the Masai broke the land into different areas with different uses so wildlife were restricted to smaller areas so population size decreased
tourism companies paid land land owners to merge land to form conservancies for tourism
Describe the management of environmental resources and the effects of human activities in the Terai region
rhinoceros and tigers were affected by abuse of the forest by locals
locals use forest for building materials
WWF introduced programmes that meant that what they take they must replace
forest corridors were built to allow tigers and rhinos to move between national parks
Describe the management of environmental resources and the effects of human activities in peat bogs
Peat bogs retain moisture so peat has been used as compost for improving soils
Describe the management of the effect of human activities on the Galapagos islands
habitat disturbance-more people more demand for water, energy and oil therefore more pollution, building caused destruction of habitats
over-exploitation of resources- fishing for exotic species decreased sea cucumber population, shark fishing led to endangered species
introduced species - eat native species, destroy habitats and bring disease. Tortoise habitats are affected.
Darwin research stations have two strategies:
1. treat problems by produced species
2.prevent introduction of introduced species
Describe the management of the effect of human activities on Antarctica
krill-fishing bats use areas with highest krill population however predators can’t adapt to find krill elsewhere therefore fishermen have a catch limit and have to evenly fish
protected areas -areas where whaling is illegal
albatrosses-threatened by pollution, hunting, poaching LONG LINE FISHING therefore boats fish at night to avoid feeding times
