paper 2 Flashcards
(156 cards)
1
Q
stages of lights dependant
A
1) Photolysis of water is when light energy causes water to dissociate into protons & electrons & oxygen is produced
H2O ⇌ 2H++ 2e- + ½O2
- h+ picked up by NADP->NADPH
-e- passed along chain of electron carrier proteins
- o2 either used in respiration or diffuse out
2) Photoionisation
when light energy excites chlorophyll electrons and raises them to higher energy levels
electrons are lost from chlorophyll ionising cholorophyll
3) Electron transfer chain
electrons pass between electron acceptor protein provide energy for h+ to be pumped into the thylakoid lumen
4) Chemiosomotic theory
proton concentration gradient results in protons diffuse through ATP synthase into the stroma ATP synthase spins releasing the energy to phosphorylate ADP with Pi forming ATP (chemical energy store)
5) the e- and h+ are use dto reduce NADP
2
Q
stages of light independant
A
calvin cycle
1) CO2 combines with RuBP , catalyzed by Rubisco in stroma
2) form two molecules of GP
3) GP is reduced to Triose Phosphate using ATP and reduced NADP
4) one carbon from Triose Phosphate is removed and goes towards creating a hexose sugar or other organic compunds and the remaining
5) carbons are used to regenerate the RuBP using energy from ATP
3
Q
fact affect photosyn
A
light intensity
- amount of light hitting chloroplast
temperature
- enzyme rubisco denature
co2 conc
- co2 to be used if calvin cycle
4
Q
2nd stage of aerobic respiration desp process
A
link reaction
- in mitocondrial matrix
- products of glycolysis actively transported into matrix
- pyruvate gets oxidised to acetate releasing CO and reduced NAD
- acetate combine with coenzyme A this forms acetylcoenzyme A
4
Q
1st stage of aerobic respiration desp process
A
glycolysis
- in cytoplasm
- glucose is phosphorylated to gp using atp
- this is then converted to troise phosphate
- this then gets oxidised to pyruvate witha net gain of reduced NAD and ATP
5
Q
3rd stage of aerobic respiration desp process
A
krebs cycle
- in the matrix
- acetylcoenzyme A bind to a 4 carbon molecule and coenzyme A will drop off forming six carbon compound
- from the six carbon compound 2 CO2 released forming 4 carbon compound this also releases 1 reduced FAD and 3 reduced NAD
ATP also phosphorylated via surface level phosphorylation
5
Q
maximising pjotosyn
additional considerations
A
green house with heating to optimal temp of enzyme
fuel burner to produce co2
cost is worth the outcome
6
Q
describe process of anaerobic respiration
in aminal cells
A
- in cytoplasm
-glycolysis occur - glucose is phosphorylated to gp using atp
- this is then converted to troise phosphate
- this then gets oxidised to pyruvate witha net gain of reduced NAD and ATP
- pyruvate reduced (gain H) and the reduced NAD gets oxidised (lose H) and form lactate NAD is reused in glycolysis
6
Q
why is nitrogen needed in an organism
A
Plants and animals require nitrogen in order to produce proteins and nucleic acids (DNA and RNA)
7
Q
4th stage of aerobic respiration desp process
A
electron transfer chain
- in cristae / inner membrane
- Reduced NAD & reduced FAD are oxidised (electrons lost)
- Electrons transferred down electron transfer chain, along electron carrier proteins that are embedded in the mitochondrial membrane cristae via a series of REDOX reactions occur
- Electrons transfer provides energy to transport protons into the mitochondrial intermembrane space, resulting in a proton concentration gradient
Protons diffuse through ATP synthase, into the matrix - ATP synthase spins, and the kenetic energy released is used to phosphorylate ADP, forming ATP
– this is Oxidative phosphorylation - The final electron acceptor in the chain is oxygen
½O2 + 2H+ + 2e- 🡪 H2O - one molecule of water is formed
8
Q
product per glucose molecule in respiration
A
2x krebs cyclye
- 2 reduced FAD
- 6 reduced NAD
- 2 ATP
- 4 co2
- 34 atp molecules
9
Q
whats npp
A
net primary production
npp= gpp - r
r = energy lost due to respiration
9
Q
describe process of anaerobic respiration
in microbes
A
- in cytoplasm
-glycolysis occur - glucose is phosphorylated to gp using atp
- this is then converted to troise phosphate
- this then gets oxidised to pyruvate witha net gain of reduced NAD and ATP
- pyruvate reduced (gain H) and the reduced NAD gets oxidised (lose H) and form ethanol and CO2 NAD is reused in glycolysis
9
Q
define biomass
A
mass of carbon within the organism also known as dry mass
9
Q
why are fertilisers needed
A
each time the crop is harvested nutrients from the soil are removed so using fertilisers replaces vital nutrients
10
Q
whats gpp
A
gross primary production is the chemical energy stored in the plant biomass in a given area result from photosynthesis
10
Q
estimating biomass
A
1) dry mass
-dry mass is the mass of the organism or tissue after all the water has been removed
-biomass = tot pop * dry mass
2) Calorimetry
- used to estimate the chemical energy stored in dry biomass
- burning the sample of dry biomass this heats a known volume of water
- The change in temperature of the water provides an estimate of the chemical energy the sample contains
11
Q
how to calc net prim prod of consumers
A
n = i - ( f + r )
n = net production for consumers
i = chem energy store in ingested food
f = chem energy lost to environment faeces
r = energy lost due to respiration
11
Q
whats meant by keneisis
A
random movement
Kinesis refers to the RATE of MOVEMENT
AND the RATE it CHANGES DIRECTION
11
Q
whats meant by taxis
A
DIRECTIONAL response
an organism moves towards/away from a stimulus
12
Q
how does iaa affect growth in a plant
A
in shoots the side of more iaa will elongate
in roots the side of more iaa will inhibit growth
12
Q
what is negative phototropism and how does it benefit survival
describe how it occurs
A
growth away from the light
boosts the root growth this anchors the plant in the soil
as iaa diffuse away from light source / to the side of shade causing these to inhibit growth
12
Q
env impact of leaching
A
- leachng is when nutrients are washed away by rain into rivers and ponds resulting in eutrophication
- this is when nitrantes stimulate growth of algae create blanket on surface of water blocking light
- prevent plants from photosynthesising on the river bed causing them to die
- decomposer bacteria feed on dead plant matter and respire using up oxygen in the water
- not enough oxygen for animals like fish to breathe so they die
12
Q
what is positive phototropism and how does it benefit survival
describe how it occurs
A
growth towards the light
boosts the amount of the light dependant reaction that occurs
as iaa diffuse away from light source / to the side of shade causing these to elongate
13
name type of light receptor and how they work
1) rods
- black and white images
- rhodopsin pigment must be broken down by light energy
- retinal convergence 3 rods bind to one bipolar neurone results in good low light vision generator potential met easier as there are 3 per 1
- low visual acuity cant see very clearly
2) cones
- coloured images
- three types of cone cell blue, red , green all contain different form of iodopsin pigment that absorb different wavelengths of light
- dont work in dark as not enough light can break down iodopsin as only one cone bond to one bipolar
neurone
- high visual acuity able to destinguish between seperate sources of light
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suggest two types of fertilisers and advantanges and disadvantages of each
1) organic (manure)
-adv = cheaper often free
-dis = nutrients in unknown quantities
2) artificial
-adv = nutrients in known quantities
-dis = nutrients very soluble so can wash away in rain (leaching)
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state units of productivity and why
kg ha–1 yr-1
recorded per unit area to standardise them
per year to take into account of the seasons
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distribution of rods and cones
rods are at periphery
cones are at fovea (center )
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what are trophic levels
producer
prim consumer
secondary consumer tertiary consumer
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name type of pressure receptor and how they work
pacinian corpuscle
- sensory neurone wrapped in plasma membrane
- stretch mediated Na+ ion channel when pressure is applied to these they get stretched and deformed
- Na+ channel open may lead to establishment of generator potential
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whats a reflex and what are some features of a reflex arc
reflex = rapid automatic involuntary movement that keep us from danger
stimuli ~> receptor ~> sensory neurone ~> relay neurone ~> motor neurone ~> effector
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control of heart rate
cardiac muscle is myogenic contract and relax on its own accord
- SAN release wave of depolarisation across atria cause it to contract
- wave reaches AVN causing it to release another wave of depolarisation travels down bundle of his down the septum to Purkyne fibres
- there is a short delay until the second beat allowing atria to pump blood to ventricles
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location of key areas controlling heart rate
sinoatrial node ( SAN ) - located in right atria known as pacemaker cells
atrioventricular node (AVN) - located between right atria and left ventricle
bundle of his - in septum
Purkyne fibres - in ventricle walls
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receptors decreasing heart rate
when blood pressure is too high this may result in damage to the walls of arteries
- more impulses to the parasympathetic nervous system
- slowing heart rate and reducing blood pressure
increase ph detected by chemoreceptors in the medulla oblongata results in decreased signals result in decreased bpm
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involvement of ns in control of heart rate
- medulla oblongata in brain control heart rate via the autonomic nervous system
- this splits into 2
1) sympathetic ns- speeds up heart rate
2) parasympathetic ns- returns heart rate back to normal
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receptors in heart that detect change in ph and blood pressure
pH = chemoreceptors
pressure = pressure receptors
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process of synaptic transmissions
1) action potential arrive at presynaptic knob
2) depolarisation of presynaptic knob result in ca2+ ion channels opening and these diffuse in
3) vesicles containing neurotransmitter move towards and bind to the presynaptic membrane and neurotransmitter is released to the synaptic cleft
4) neurotransmitter diffuse down conc grad to postsynaptic membrane
5) neurotransmitter bind to the complementary receptor sites on the postsynaptic membrane
6) Na+ ion channel open and they diffuse in may lead to depolarisation
7) neurotransmitter degraded by acetylcholinesterase and released from the receptor Na+ ion channel close and resting potential etablished
15
whats pos/neg gravitropism
negative = away from gravity
iaa diffuse to the bottom cause shoot to grow upwards
positive = towards gravity
iaa diffuse to lower side if root and inhibit growth so grow down
15
etablishing resting potential
1) active transport and cotransport of 3 Na+ ions out and 2 K+ ions in and more permeable to k+ this results in tese diffuse out make it even more -ve
2) create electrochemical gradient
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whats is hyper polarisation
period where act pot cant be created
enusres act pot only goes one direction
15
how is synaptic transmission unidirectional
1) receptor sites only on the postdynaptic neurone
2) neurotransmitter only released from the presynaptic neurone
15
receptors increasing heart rate
during exercise blood pH will decrease do to respiration producing carbon dioxide or lactic acid
- heart rate will need to increase in order to remove the acidic conditions so enzymes dont denature
- more impulses sent to the sympathetic nervous system so higher heart rate
if blood pressure is too low then there may be insufficient oxygen concentration being delivered to the respiring cells
- more impulses sent to the sympathetic nervous system so higher heart rate
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whats the all or nothhing principle
either act pot created or not they are always the same strength
ensure organism only responds to the stimuli that are large enough to create act pot
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features of motor neurone
cell body
dendrites - carry act pot to surrounding cell
axon - carry nerve impulses along neurone
schwann cells - wrap around axon form myelin sheath and doesnt allow charge to pass through
15
define epigenetics
- altering in the function of a gene without changing the base sequence of the nucleotides
- these characteristics are also heritable
15
two types of epigenetics and how they affect transcription
decreased acetylation of histones
- stops transcription of the gene as dna coiled too tightly to be transcribed
increased methylation of dna promoter sequence of the molecule
- come from smoking and processed meat
- transcription factor is unable to bind to the promoter sequence as it no longer fits so transcription stops
15
key features of nevre impulse
resting potential = -70 mv
depolarisation - Na+ ion channel open they diffuse in and k+ ion channel open they move out voltage exceed the -55 mv threshold and goes up to creating an action potential
repolarisation - Na+ ion channel close and the k+ ion channel open and they keep diffusing out
hyperpolarisation = below -70v
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fatcors affecting speed of conduction
1) myelin sheath
- saltatory conduction
jump between node of ranvier
2) axon diameter
- wider diameter less resistance so more speed
3) temperature
- ions diffuse faster and enzymes work at more optimal temperature
16
how does menopause result in high risk of cancer
increased oestrogen and therefor increased transcription as the transcription factorss are activated by the oestrogen and may result in unlimited cell division
may use molecule with complementary shape to block oestrogen binding site on the tf
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inhibition at a synapse
1) Cl- ions diffuse into postsynaptic neurone and k+ diffuse out
2) result in hyperpolarisation
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two types of summations
temporal = one neurone send repeated signals to acheive action potential
summation = many neurones bind to one post synaptic neurone
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whats RNAi and whats it used for
interfering rna and stops tranlsation of a target gene
join to the mrna molecule via comp base pairing and breaks phosphodiester bonds in the mrna
therefor rna cant be translated and the gene wont be expressed stopping production of polypeptide
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describe sliding filament theory
2) Calcium ions are released from the sarcoplasmic reticulum
3) Calcium ions bind to tropomyosin this change their position revealing the Myosin binding sites on the actin molecules
4) myosin heads bind with these sites, forming actin myosin cross-bridges
5) myosin perfom power stroke and pulls the actin and release adp + pi
6) atp bind to myosin head and it detaches from the actin
7) myosin hydrolyses the atp and myosin heaad returns back to its relaxed state
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neuromuscular junction
1) presynaptic membrane carries action potential causes calcium ions to diffuse into the neurone
2) This stimulates vesicles containing the neurotransmitter acetylcholine (ACh) to fuse with the presynaptic membrane and get released
3) the acetylcholine diffuses across the neuromuscular junction and binds to receptor proteins on the sarcolemma
3) This stimulates ion channels in the sarcolemma to open, allowing sodium ions to diffuse in
4) results in depolarisation of the sarcolemma, generating an action potential that passes down the T-tubules towards the sarcoplasmic reticulum releases calcium ions
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how does technology benefit methods of sequencing the genome
automate sequancing and constantly improve efficiency
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cell division equation
1 * 2*10^number of division
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producing dna fragments
1) reverse transcription
- add many mRNA for specific protein and add reverse transcriptase and free nucleotides
- reverse transcriptase adds complementary nucleooutides to mRNA base sequence
- will have created single stranded cDNA
- dna polymerase is added and forms a double stranded dna as it condense adjacent nucleotides
2) restriction endonuclease
- enzyme cut dna leaving sticky or blunt end
3) gene machine
- dna sequence put into computer and and this creates fragment
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how oestrogen acts as transcription factor
- oestrogen diffuse into cell across phospholipid bilayer as it is a lipid soluble molecule
- oestrogen binds to a complementary receptor on the transcription factor
- this binding results in the transcription factor changing shape and binding to promoter region of the dna
- rna polymeraise is stimulated and phosphodiester bonds form between adjacent rna nucleotides
- mrna molecule is made and then this expresses gene
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how do mutations result in production of tumors
if mutation occurs in gene coding for proto-oncogene then this is converted to a oncogene and this is constantly activated and results in rapid uncontrollable cell division resulting in a tumor
if mutation / methylation occurs in the promoter sequence in the dna molecule of the tumor supressing gene then these wont be expressed / transcribed result in uncontrollrd cell growth formation of tumor
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types of tumor and their properties
1) benign
dont metatstecise (spread)
divide at a slow rate
2) malignant
do metastacise (spread)
divide at rapid rate
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regulation of transcription
transcription factors
- bind to promoter sequence of the dna molecule stimulating the rna polymeraise
- results in gene turned on and transcription occurs OR gene turned off and no transcription occurs
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diff between 2 types of muscle fibre
1) Fast twitch muscle fibres
- contract rapidly
- rely on anaerobic respiration for ATP supply (lactate produce fatigue quickly )
- short bursts of high intensity activity
- fewer capillaries
- large store of glycogen
2) Slow muscle fibres
- contract slower
- rely on aerobic respiration for ATP production
- log duration low intensity
- dense network of capillaries
- small amount of glycogen present
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why its easier to determine the genome when studying the proteome of prokaryotes
as they lack introns and all their dna is used to make proteins
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what is a stem cell
undifferentiated cell that can continually divide and become specialized
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types of mutation
1) addition
- adding an extra nucleotide result in frame shift
2) deletion
- remove a nucleotide result in frame shift
3) inversion
- section of bases is removed from sequence and gets replaced flipped
4) duplication
- when a particular base is duplicated result in frame shift
5) substitution
- a nucleotide is swapped for another one
6) translocation of bases
- section of bases detach from chromosome and join onto a completely different chromosome
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types of stem cell and how they divide
totipotent
- produce any type of body cell an unlimited amount of times
- only in embryo
pluripotent
- divide into almost every cell an unlimited amount of times present in embryos
multipotent
- divide to produce limited amount of cells and divide a limited amount of times
bone marrow only make blood cells
unipotent
- divide to become only one type of cell
cardiomyocites
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what are pluripotent stem cells and how can they be made
- take sample from liver
- switch genes off that made those cells specialized
- cells turned back into pluripotent state
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what is epigenetics
heritable change in a gene function without changing dna base sequence
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function of kidney
- selectively reabsorb the useful molecules back into the kidney and
- wont find proteins or blood cells in the urine as these are too big to be filtered from glomerulus to the renal capsule
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three possible outcomes of invivo
1) dna sticky ends may have rejoined with itself
2) plasmid sticky ends may rejoin with itself
3) the plasmid and dna combination may have not got into the cell
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methods of cloning dna fragment in another cell
invivo
- cloning inside a living organism
- dna is cut using restriction endonuclease and this leaves sticky end
- promoter region is added and this acts as binding site for rna polymerase to trigger transcription
- terminator sequence must be added at end of the sequence result in rna polymerase to fall off
- the vector is the plasmid in bacteria and same restriction endonuclease is used to cut section out the plasmid so fragment is complementary to this area
- host cell is then heat shocked of added sol of ca ions to increase permeability of the host cell
- vector enter cytoplasm of host cell
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nephron structure
afferent arteriole ~> glomerulus ~> efferent arterioles
surrounding that glomerulus is the renal capsule ~> proximal convoluted tubule ~> loop of henle ~> distal convoluted tubule ~> collecting duct
capillaries wrap around whole thing
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methods of cloning fragments in macheine
invitro / pcr
- temp increased to 95°C and this separates the h bonds between the base pairs form 2 single strands
- decreased to 55°C and this allows primers to attach
- increased to 72°C this is optimal temperature for taq polymeraise to join adjacent nucleotides
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whats first step of nephron and adaptations
1) ultrafiltration
- high hydrostatic pressure in the glomerulus force out water and small molecules into the renal capsule
-filtration first occurs when blood passes through the fenestrations in walls of capillary
-the basement membrane adds another layer of filtration
- podocytes = cells that wrap around the capillary and have tiny gaps adds another stage of filtration
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whats second step ant nephron
2) selective re-absorption
- glomerulus filtrate passes through the proximal convoluted tubule and the desired content gets reabsorbed back into the blood
- sodium ion conc is low in pct cell as they are actively transported out of pct into the blood
- sodium ion flow down the conc grad from lumen of pct to the cells in the lining of the pct carry a glucose molecule with it
- glucose then diffuse from lining of the pct to the blood stream
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whats third step at nephron
3) in the loop of henle
- sodium ions actively transported out of the ascending limb
- accumulation of sodium ions outside nephron lower water potential
- water diffuses out and then gets reabsorbed into the blood
decendinng limb the walls are permeable to water as they are much thinner
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whats fourth step at nephron
4) dct and collecting duct
- the sodium ions atcively transported out the loop of henle the filtrate then moves to the distal convoluted tubule and is very dilute
- more water diffuse out of the dct and collecting duct any remaining filtrate forms urine
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1) checking if the plasmid took up dna fragment
2) checkin that host cell took up the plasmid
marker genes
- specific genes on plasmid
- used to identify if the plasmid took up by host cell
three different types of
marker gene
- antibiotic resistance
- genes coding for flourescent proteins
- genes coding for enzymes
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using antibiotic resistant marker genes
gene for resistance to tetracycline and ampicillin on a plasmid
the tetracycline resistance gene is deliberately disrupted and no longer functional
grow bacteria on agar tranfer colonies onto amipcillin infused agar transfer the end result onto a second agar block infused with tetracycline
only the bacteria that lived on ampicillin and died on tetracycline have plasmids
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using flourescent genes in determining if the plasmid has been taken up
flouresent green gene is disrupted by the plasimd that is inserted
no longer flourescent
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genetic counselling
- screening for prescence of a specific allele
- can be used to give specific medicine
- people may be given advice about thier disorder and what options are available for you
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what are dna probes and what are they used for
small sections of dna that are labeled floyrescently or radioactively that can be easily identified in order to locate a specific gene
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using enzyme markers in determining if the plasmid has been taken up
lactase enzyme makes some things appear blue
gene for the enzyme is inserted into plasmid in middle of gene for the enzyme and this disrupts the gene and the enzyme not created
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fisrt step in genetic fingerprinting
1) dna is collected
2) pcr may be used to create larger sample
3) restriction endonuclease enzyme used to cut dna fragment
4) samples put into wells on gel plate and electrical voltage is applied to it
5) the negatively charged dna is attracted to the positive terminal and the shorter peices move further
6) put alkali sol on the gel make dna single stranded
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genetic fingerprinting
vntr
variable number tandem repeats
repeated sequence in the intron probability of two peole having same one is tiny
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fourth step in nitrogen cycle
denitrification
- Denitrifying bacteria use nitrates in the soil during respiration
- This process produces nitrogen gas, which returns to the atmosphere
- only happen in anaerobic conditions
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first step in nitrogen cycle
nitrogen fixation
- atmospheric nitrogen turned into ammonium ions
- happens by the nitrogen fixing bacteria that may be free living in the soil or have symbiotic relationship with legumionus plants can live in roots
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second step in nitrogen cycle
ammonification
- organic molecules get decomposed and turned into ammonium ions
- carried out by saprobionts
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prevent de nitrification
plough feilds to aerate
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third step in nitrogen cycle
nitrification
- ammonium ions are converted to nitrates then nitrites
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third step in phosphorus cycle
plants get eaten by animals and they use the phosphate ions in synthesizing biological molecules
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first step in phosphorus cycle
erosion of rocks release phosphate ions into soil or water
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second step in phosphorus cycle
plants assimilate/take in phoshate ions
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fith step in phosphorus cycle
mineralisation
bacteria in soil break down phosphate ions into inorganic forms
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fourth step in phosphorus cycle
animals die and phosphate return to the soil
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why do we need phosphorus
needed in many biological moleculees
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returning high blood glucose levels back to the norm
1) after eating blood glucose increase
2) beta cells in islets of langerhans in pancreas release insulin (and bind to complementary shaped receptors in the liver this results in the release of chemicals into the cell results iin vesicles with channel proteins fusing with the membrane)
3) liver cells become more permeable to glucose as more channel proteins are added to the membrane result in more fac diff enzymes activated that turn glucose into glycogen
4) glucose there for removed from blood and stored as insoluble glycogen and this therefor lowers glucose levels
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factors affecting blood glucose levels
increase - after eating food
decrease - after exercise
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define genotype
all the genes within an organism
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whats is negative feedback
when any deviation from the norm is restored to their origional levels
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define phenotype
physical expression of the genotype may be influenced by the environment
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define allele
different forms of the same gene
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sixth step in phosphorus cycle
phosphate ions get washed into water and bet assimilated by plants again
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osmoregulation too high water potential
1) drinking lots of water increases water potential of blood
2) detected by osmoreceptors in hypothallamus
3) less ADH produced and released into the blood
4) distal conveluted tubule and collecting duct become less permeable to water
5)larger volume of dilute urine
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returning low blood glucose levels back to the norm
1) after excerise or no digestion of carbohydrates blood glucose concerntration decreases
2) alpha cells in islets of langer hans in pancreas release glucagon and adrenal gland releases adrenaline
3) glucagon attach to receptors on the liver and this results in the activation of the adenylate cyclase protein this converts ATP into cAMP
4) cAMP activates protein kinaise this is an enzyme that hydrolyses glycogen to glucose
4) glucose released back into blood rasie levels of blood glucose
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diabetes
type 1
- unable to produce insulin
- starts in childhood
- treatment involve injection of insulin
type 2
- receptors lose responsiveness to insulin
- usually develop due to poor diet
- treatment involves increasing exercise and controlling intake of carbohydrates
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role of the liver
- glycogenolysis = hydorlysis of glycogen to glucose
- gluconeogenisis = creating glucose from other molecules
- glycogenisis = converting glucose to glycogen
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osmoregulation too low water potential
1) not enough water in the blood decrease water potential
2) detected by the osmoreceptors in the hypothallamus
3) more ADH produced and released into blood
4) binds to receptors on distal convoluted tubule and collecting duct water permeability increases
5) more water reabsobed back into blood more concentrated urine
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types of competiotion between species
interspecific comp - members of diff species compete for resource may be food or water
intraspecific competition - within a species may be for mates
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types of selection
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types of speciation
allopatric - geographically isolated leading to reproductive isolation
sympatric - difference in behaviour means they are reproductively isolated
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how to ensure sampling is representative
- random sampling elimminate bias
- large num of samples
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issues wit mark rel recap
- assume population size is constant and is no death birth
- asssume they do redistribute evenly
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mark release recapture
1) initial sample captured and marked with a mark that is all weather resistant and doesnt affect the animal
2) release marked individuals and allow them time to evenly distribute
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random sampling of non moving over non-even distribution
1) belt transect have tape measure going away from factor and then every 10cm place the quadrat
2) repeat with 30 more transects paralel to the previous one
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random sampling of non moving over even distribution
1) two tape measures lay out at right angle create gridded area
2) use random number generator to get coordinates
3) repeat atleast 30 times and calculate mean
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mark release recapture calculation
(caugth in first sample x caught in second sample) / marked in second
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succession
1) pioneer species colinise the hostile environment
2)as more species grow the abiotic factors change and this results in the formation of the climax community
3) some species outcompete others as they may block the light
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ethics of mark release recap
- non toxic
- cant increase predation
- cant decrease reproduction
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Genotype
Genetic constitution for that organism
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Phenotype
Physical expression of genotype also influenced by environment
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Homozygous
Pair of chromosomes carrying smae allele
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Heterozygous
Pair of chromosomes carrying different alleles
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Recessive allele
Only expressed in absence of dominant allele
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Dominant allele
Always expressed in phenotype
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Cod dominant
Both alleles equally dominant both expressed
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Multiple alleles
More than two alleles for single gene
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Sec linked
Gene Whos locus is on x chromasome
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Autosomal linkage
Genes located on same chromosome
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Epistaxis
One gene modified the expression of another gene
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Mono hybrid
Genetic cross where characteristics determined by one gene
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Do hybrid
Genetic cross Whos characteristics determined by two genes
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Bands of sarcomere
Z Line at end
I band at end only actin
M line middle of myosin
H zone all myosin no actin
A band actin myosin over lap
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Potentials of the cell
Resting =-75
Depolarisation = +30
Hyperpolerisation = -120
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Movement of the sodium potassium pump
3 na+ out and 2 k+ in and then this shuts but the k channels remain open and allow k+ to diffuse out down conc grad makes more -ve
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Ways of predicting allele frequency
Hardy wineberg equation
P^2. +. 2pq. + q^2. =1 This is the genotypes
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Assumptions of hardy Weinberg eq
-mating is random
-no natural selection occur
-no mutation or genetic drift
-population size is infinite
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