Question | Answer |
Type of cells in xylem | Tracheids & Vessel elements; dead |
Type of cells in Phloem | Sieve elements & companion cells; alive |
Xylem transports | Water & inorganic solutes |
Phloem transports | Products of photosynthesis (sugars) and signalling molecules/proteins |
Direction of phloem | source --> sink |
Direction of xylem | roots --> leaves |
Mechanism of xylem transport (2) | Transpiration
Cohesion-tension |
Mechanism of phloem transport (2) | Osmotic pressure
Bulk flow |
How to deal with xylem breakage vs. phloem breakage | xylem: block off pits & reroute
phloem: block sieve plates with p-protein |
Embolism | gas-filled void (xylem) |
Maple syrup is in the: | XYLEM
* bizarre because it's only supposed to carry water |
Chlorosis | yellowing due to the loss of chlorophyll |
C4: two kinds of cells | Mesophyll and Bundle sheath |
What happens in mesophyll cells? | CO2 comes in, light reaction occurs. |
What kind of cell does PEPcase work in? | Mesophyll OR a cell from CAM plants |
Dark reactions in C4 plants occur in... | Bundle sheath cells |
Bundle sheath cells have a high/low PCO2 | high |
Calvin cycle is the light/dark reaction | DARK |
Aerenchyma | gas-filled space in aquatic plants...surrounds root cells. Allows transport of CO2 from anoxic sediments to photosynthetic tissues |
Hemoglobin, structure: | Protein + Heme + Fe2+ |
Chlorocruorin structure: | Protein + Porphyrin + Fe2+ |
Hemerythrin structure: | Protein + Fe2+ |
Hemocyanin structure: | Protein + Cu2+ |
How many oxygens can Hemoglobin bind? | 4/tetramer |
How many oxygens can Chlorocruorin bind? | One/porphyrin group |
How many oxygens can hemerythrin bind? | 8/octomer |
How many oxygens can hemocyanin bind? | one/ 2 Cu2+ |
Does Hemoglobin display "cooperativity"? | YES |
What causes Bohr effect? | Change in pH or PCO2 |
myoglobin, where is it found & affinity properties | found in muscle
Higher oxygen affinity than Hb |
Neuroglobin, where is it found? | Brain & retina |
Cytoglobin, where is it found? | All cells! |
Define stenohaline | Survive across a narrow range of salinities |
Define euryhaline | Survive across a broad range of salinities |
Anhydrobiosis | Survive losing water |
Who has more urine, saltwater or freshwater fish? | Freshwater > saltwater |
Ion flux in saltwater vs. freshwater fish | Saltwater: passive in, active out
Freshwater: active in, passive out |
Which kind of teleost fish has tight junctions? | Freshwater |
Na+ gradient drives transcellular Cl- transport in: | Saltwater fishes |
Na+ gradient is driven by electrochemical gradient from H+ pump and Na+K+ ATP-ase in: | Freshwater fishes |
Poikilotherms | have more than one temperature setpoint
generally ectotherms |
Keeping internal temperature constant | homeotherms |
Q10 | ratio of the rate of a process over the rate of the same process at a temperature 10 degrees lower |
high km means... | low affinity |
Kcat = | number of molecules of substrate processed per unit time at saturation |
Conduction, convection, and thermal radiation are all examples of... | Dry heat transfer |
BAT increases with... | acclimation/acclimatization |
If heat transfer between outgoing and incoming vessels is allowed in counter-current heat exchange you can expect: | less heat to be lost to outside world & less energy required to re-heat incoming blood |
Where does ectotherm heat come from for:
Plants?
Animals? | Plants: futile cycling
Animals: muscle contraction |
Define the isothermal line on graphs.. | How temperature would vary if there were no endothermy |
Respiratory exchange ratio (RER) | CO2 produced : O2 consumed
(also called respiratory quotient) |
What does Fv/Fm measure? (plants) | How well PSII is working |
Can chloroplasts move? | Yes |
Chloropyhyll is contined in___ | Thylakoids |
Thylakoid reaction makes: | ATP and NADPH |
Is it light dependent or light independent that produced ATP and NADPH? | Light-dependent |
Energy input for light dependent reactions is? | photons |
Energy input for light-independent reaction is? | light dependent reaction! |
Uses water and produces oxygen, light dependent or independent? | Dependent |
Uses CO2 and produces sugars, light dependent or independent? | Independent |
Uses ADP and NADP+, light dependent or independent? | Dependent |
Produces ADP and NADP+, light dependent or independent? | Independent |
Produces ATP and NADPH, light dependent or independent? | Dependent |
Rotenone inhibits which complex | 1 |
Name of Complex 1 in mitochondrial ETC | NADH Dehydrogenase |
Name of complex 2 in mitochondrial ETC | Succinate dehydrogenase |
Name of complex 3 in mitochondrial ETC | cytochrome bc1 complex |
Which complex isn't transmembrane in mitochondrial ETC? | 3 |
Name of complex 4 in mitochondrial ETC? | Cyt C oxidase |
Name of complex 5 in mitochondrial ETC | ATP Synthase |
Cyanide, Carbon monoxide, and Azide all inhibit... | Complex IV
Stops donation of oxygen |
How do colligative antifreezes work? | Increase total [solutes] in body fluids, NOT chemical properties
idea: more stuff = lower melting and freezing pt |
Non-colligative antifreeze method | Specialized chemical properties
Bind to certain planes of growing ice crystal |
Which is more temperature dependent, light or dark rxn? | dark!
Decreased temperature, Calvin cycle slows |
Adaptation
Acclimatisation
Acclimation | Evolutionary
In Field
In Lab |
Frank-starling response | Heart responds to increased blood by increasing contraction strength
An example of +ve regularion, heart pumps more vigorously |
Energy input for ETC: Chloroplast vs Mitochondria
(what and where?) | Chloroplast: Photons at light harvesting complex I and II
Mitochondrion: NADH, FADH2 at complex I and II |
Main electron transfer molecules: Chloroplast vs Mitochondria | Chloroplast: PQ and PC
Mitochondria: UQ and Cyt C |
Signature redox step of chloroplast vs mitochondria | Chloroplast: h2O --> O2
Mitochondria: O2 --> H2O |
Energy output of chloroplast vs mitochondrial ETC | NADPH and ATP chloroplast
ATP mitochondria |
Why do Cyanide/CO/Azide block ETC? | They block complex IV so you can't donate the final electron |
How does myogenic regulation differ from Frank-Starling response? | Myogenic is negative feedback where frank-starling is positive |