Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Unit 4

No description

Emily Wright

on 11 June 2014

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Unit 4

It has been estimated that only 5% of the light energy hitting the surface of a leaf reaches the chloroplasts to be used in the synthesis of organic material. Suggest why?
Suggest reasons for the net effect of the oceanic processes on the carbon content of the atmosphere
Genetic Mutation
The base/s of genetic material changes leading to a change in the amino acid and so the protein will not function the same
HIV and TB
Explain how HIV is able to enter cells such as T-helper cells and macrophages
On the wild side
Key terms
Infection, immunity and forensics
Unit 4
incorrect wavelength
excess of light, at the max photosynthesis so no more light can be used
Doesn't hit the choloplast
With reference to the structure of a chloroplast, explain how the light energy from light is made available in ATP molecules for the synthesis of organic molecules.
thylakoid membrane
light hits the chlorophyll and rises the energy levels of electrons in the chlorophyll
electrons are released
series of RADOX reactions
Decrease of the electrons energy
drives the synthesis of ATP from ADP and Pi
By photophospholation
ATPase synthesises ATP through chemiosmosis
the lost electrons in PS11 are replaced by photolysis
Suggest why the development of corn cobs, suitable for producing cereal products, depends on the rate of carbon fixation
Carbon fixation produces GP which is then converted to GALP
This is then converted to sugar, which can be converted into starch
Faster carbon fixation means faster glucose production
the rate of growth depends on the rate of carbon fixation
increased GPP
Explain the term limiting factor with reference to photosynthesis
It is a factor that limits the rate of photosynthesis
If this factor is increased the rate of photosynthesis will also increase
During the light independent stage of photosynthesis, oxygen is produced by photolysis. Describe the process and explain its role.
splitting water with light
H20 = 1/2 02 + 2H+
electrons replace the electrons lost from PS11
Hydrogen ions picked up by NADP
NADPH+ is used in the light independent stage of photosynthesis
Explain why temperature can be a limiting factor in photosynthesis
Affects the rate of enzyme activity
in the light dependent stage
Describe how products of photosynthesis are transported in the plant
Active process which requires ATP
in phloem tubes
continuous tube
mass flow
bi-directional flow
oxygen by diffusion
Describe the Calvin cycle
Take place in the stroma
during the light-independent stage
RuBP is required for carbon dioxide fixation
To provide GP
Reduced NADP is oxidised
GP is reduced to GALP
Energy from ATP being broken down
GALP is used to from glucose and to regenerate RuBP
Describe and explain how carbon can be removed from terrestrial part of the cycle from long lengths of time
Planting trees
Carbon fixation in photosynthesis
Carbon is locked into the trees
trees live for a long time
when it dies it will become peat
which is a carbon sink
some carbon is taken up be marine animals
forms calcium carbonate/shells
photosynthesis - algae or plankton
marine organisms die and form sediment on sea beds
Suggest how the qualities of carbon dioxide released by the combustion of fossil fuels could be reduced
Improved fuel efficiency
Increased use of public transport
burn hydrogen or a biogas instead of petrol
renewable energy
planting trees
With reference to an example, explain what a carbon sink is
Locks up carbon dioxide for a long time
Peat bog, trees, coal, limestone, fossil fuels, shells, chalk
Explain what is meant by the term global warming
Increase in temperature of the earth's mean surface
Carbon dioxide is a green house gas
These gases trap heat in the atmosphere
increased greenhouse effect
an effect of this is melting ice caps, flooding and climate change
Suggest a type of plant biofuel
wood, agricultural waste
State the meaning of sustainable
Can carry on using it long into the future. It is renewable
Suggest why using plant biomass to generate electricity is through to be more sustainable than using fossil fuels
Less atmospheric pollution because its just replacing what has recently been absorbed by phototsynthesis
whereas fossil fuels represent carbon that is returned to the atmosphere after it has been out of the cycle for a long time
therefore biomass contributes less to global warming than fossil fuels
Explain one reason why an increase in the rate of decay might increase the rate of global warming even more
Increase enzyme activity means more CO2 is released
increase microorganism respiration
more CO2 therefore more green house gas effect
The GP120 on the HIV host cell attaches to two of the CD4 receptors on the call
The surface membrane of the cell and the viral envelope fuse
The viral DNA and enzymes enter the cell
Describe the sequence of events following infection of these cells by HIV, that may lead to death
The viral RNA is copied by reverse transcriptase into a double stranded DNA
This is then inserted into the hosts DNA using intergrase
This viral DNA is then translated by the cells own ribosomes and so becomes the virus production cell
T-Killer cells begin to attack the T-helper that is infected lowing the T-helper cell count
This means less T-killer and B-helper cells are activated
Opportunistic infections begin to set in due to the viral overload in the immune responsible
Also, the number of T-helper cell are further decreased by the viral protein which cause cell lysis as they burst out of the cell
Serious infections will cause death as the immune system cannot fight them off
Suggest why effective treatment of HIV in human populations will require the continual development of a mixture of many new drugs
HIV's undergoes rapid mutations
Using a mixture of drugs will give a higher chance of its destruction
The immune system
State two characteristic features of antibiotic
Antigen binding site
Produced by plasma cells
Label pathogens as non-self
Suggest why cephoilosporins are bactericidal antibiotics
Bactericidal antibiotics kill the bacteria
it inhubits the production of petidoglycan
This causes holes in the bacterial call wall as it replicates and so they lyse
Suggest why quinolones are bacteriostatic
Bacteriostatic antibiotic inhibit cell replication
without the ability to synthesise DNA, the Bacterica cannot perform binary fission
Protein synthesis
The formation of mRNA during transcription in the nucleus
The DNA unwinds to reveal the gene needed
Free mRNA nucleotides form a complimentary strand to the DNA template strand forming a RNA polymerase
Full transcript