Unit 5 - Energy transfers between organisms Flashcards
What do plants need energy for?
- Photosynthesis
- Active transplant
- DNA replication
- Cell division
- Protein synthesis
What do animals need energy for?
- Muscle contraction
- Maintenance of body temperature
- Active transport
- DNA replication
- Cell division
- Protein synthesis
Equation for photosynthesis
6CO2 + 6H2O + Energy –> C6H12O6 + 6O2
Aerobic respiration
Anaerobic respiration
- Aerobic - respiration using oxygen
- Anaerobic - respiration without oxygen
Equation for aerobic respiration
C6H12O6 + 6O2 –> 6CO2 + 6H2O + Energy
Anaerobic respiration
Products in plants and animals
In plants and yeast - ethanol and carbon dioxide is produced and energy
In humans - Lactate is produced and energy
How is ATP synthesised
ATP is synthesised via a condenstation reaction between ADP and inorganic phosphate using energy.
The energy is stored as chemical energy in the phosphate bond.
The enzyme ATP synthase catalyses this reaction.
Properties of ATP that makes is a good energy source
1) ATP releases only a small, manageable amount of energy at a time so no energy is wasted as heat.
2) It is a small, soluble molecule so it can be easily transported around the cell
3) It is easy broken down so energy can be released instantaneously
4) It can be quickly re-made
5) It can make other molecules more reactive by transferring one of its phosphate groups to them
6) ATP can’t pass out of the cell, so the cell always has an immedicate supply of energy
What is metabloic pathway?
A series of small reactions controlled by enzymes
What is phosphorylation
Adding phosphate to a molecule
What is photophosphorylation
Adding phosphate to a molecule using light.
What is photolysis
The splitting of a molecule using light energy.
What is photoionisation
When light energy excites electrons in an ato or molecule, giving them more energy and causing them to be released. The release of electrons causes the atom or molecule to become a positively charged ion.
What is hydrolysis
The splitting of a molecule using water
What is decarboxylation
The removal of carbon dioxide from a molecule.
Biomass
The mass of living material which can be measured as mass of carbon or dry mass per unit area.
What is gross primary production
The amount of chemical energy made avaliable by a producer
What is net primary production
The amount of energy available for consumers in the plant’s biomass after plant respiratory losses
Nitrogen cycle
1- Nitrogen fixation- Bacteria in root nodules turn N2 gas into ammonia that go onto form ammonium ions
2-Nitrification- ammonium is steb by step converted into nitrate ions by nitrifying bacteria
3- Denitrification- Nitrates in the soil converted into N2 gas by denitrifying bacteria in anaerobic conditions
4- Ammonification- Saprobionts convert dead organisms into ammonia, going onto form ammonium ions- this also occurs with animal waste
Phosphorus cycle
1- Phosphate ions are released from rocks into the soil by weathering
2- Mychorhizae allow phosphate ions to be absorbed into plants roots
3- They are passed through the food chain by consumption and excretion
4- Waste products and dead material are broken down by saprobionts
5- The original weathering releases phosporus into bodies of water aswell- this is taken up the food chain and passed through
6- Guano is the fecal matter of birds which contains a high level of phosphorus
Eutrophication
- Mineral ions leached from the fertilised field stiumate the rapid growth of algae in ponds and rivers.
- Large amounts of algae block light from reaching plants below.
- Eventually plants die because they’re unable to photosynthesise enough.
- Bacteria feed on the dead plant matter. The increased numbers of bacteria reduec the oxygen concentration in the water by carrying out aerobic respiration.
- Fish and other aquatic organisms die because there isnt enough dissolved oxygen.
What does the stroma contain?
Enzymes, sugars and organic acids
Light dependent reaction steps
1) Photoionisation- electrons excited by light energy to higher energy state
2) The electron void which is left causes a water molecule to split (Photolysis)
3)The excited electrons move down the electron transport chain- using energy to actively transport H+ ions into the stroma
4) The electrons are hit again by light at a different photosystem causing them to reduce NADP
5) H+ ions move by facilitated diffusion- providing energy for ATP synthase to synthesise ATP
Calvin cycle
RuBP(5c) + Rubisco —-> 2GP(3c)
2GP+ 2NADPH + 2ATP—> 2triosephosphate(3c) + 2ADP + 2NADP
2 Triose phosphate + ATP —> RuBP + ADP
How much of each product is produced per cycle (Photosynthesis)
3 ATP
2 NADPH
2*triose phosphate
How many cycles to produce a glucose
6 cycles
Optimum conditions for photosynthesis
Red/ blue light
Temperature around 25 degrees
CO2 around 0.4%
Methods of keeping conditions constant (Photosynthesis)
CO2- Propane burner
Light- Lamp
Temperature- Greenhouses
How growers can increase plant growth
Co2 generator
Greenhouse/Lamps
Heating/ Cooling systems
Where does each stage of respiration occur
Glycolysis- Cytoplasm
Link reaction- Matrix
Krebs cycle- Matrix
Oxidative phosphorylation- Cristae membranes
Net products of Glycolysis
2*Pyruvate
2ATP
2Reduced NAD
Anaerobic respiration in animals and plants equation
Pyruvate—–>Lactate (Reduced NAD to NAD)
Pyruvate—–> Ethanal——-> Ethanol (-CO2 NADH-NAD)
Net products of link reaction
2CO2
2NADH + 2 from gylcolysis
2*Acetyl COA
What is produced in 1 krebs cycle
1 x coenzyme A
2 x CO2
1 x ATP
3 x reduced NAD
1 x reduced FAD
Steps involved in oxidative phosphorylation
1) Hydrogen atoms are released by reduced co enzymes and slit into protons and electrons
2)These electrons move down the electron transport chain + lose energy at each carrier
3)This energy is used by electron carriers to pump protons from the mitochondrial matrix into the intermembrane space forming an electrochemical gradient
4) Protons move down the electrochemical gradient (Chemiosmosis)
5)As they move throgh ATP synthase- ATP is synthesised from ADP + Pi
6) At the end of the electron transport chain, protons, electrons and O2 combine to form water- oxygen is the final electron acceptor
Types of base mutation
Substitution
Deletion
Addition
Duplication
Inversion
Translocation
Why do not all mutations change sequence of amino acids
- Genetic code is degenerate
- Some amino acids are coded for by more than one codon
Which types of mutation are more likely to affect amino acid sequqence
Additions, duplications and deletions
Why are additions/mutations more likely to change amino acid sequence?
They cause a frameshift
Types of mutagenic agents
Ones that act as a base
Some that alter bases
Some that change strucutre of DNA
Equation for net primary production
gross primary production - respiratory loss
NPP = GPP - R
Equation for net production for consumers
N = I - (F + R)
N = Net production
I = Chemical energy ingested by food
F = Chemical energy lost in faeces and urine
R = Energy lost through respiration
Allopatric speciation
- Geographical isolation
- Seperate gene pools
- Variation due to mutation
- Different selection pressures
- Different reproductive suucess
- Leads to change in allele frequency
- Eventually organisms are so genetically different that they cannot reproduce and are deemed to be different species
Describe how to use the mark-release recapture methord
- Capture sample, mark and release
- Mehtord of marking animal that does not harm them or make more visible to predators
- Leave sufficient time for lizards to randomly distribute before collecting a second sample
- Number in first sample x number in second sample divided by number of namrked lizards in second sample
Draw link reaction
Draw calvin cycle
Draw krebs cycle
Draw glycolysis
Draw phosphorus cycle
Draw Nitrogen cycle
Advantages of natural fertiliser
- Improve soil structure
- Released over long time periods
- Leaching less likely
Disadvantages of natural fertilisers
- Need decomposing take time to release
- Not as effective fertilisers
Advantages of artificial fertilisers
- Easy to know how much to apply
- Nutriens present are concerntrated- smaller amounts are needed
- Lower cost
- Easy to apply evenly and clean
Disadvantages of artificial fertilisers
Can result in leaching + Eutrophication
