Bio P1 Flashcards
What do accessory pigments do in photosynthesis?
They pass energy to primary ones.
What are the two types of potometer?
- Measures mass lost
- Measures how far bubble moves along tube
Where does oxidative phosphorylation take place?
Intermembrane space and inner membrane (cristae)
What are the properties of cellulose?
- High tensile strength
- Unreactive
- Flexible
- Forms H bonds with neighbouring chains
Why might bronchiole diameter be reduced?
- Contraction of smooth muscle
- Inflammation
- Excess mucus production
Structure of Cholesterol
4 Hydrocarbon rings, Hydrocarbon chain on one end and OH group on the other.
NO FATTY ACID TAIL
What did scientists originally think light did to auxin?
Scientists used to think that Light destroyed auxin
Reasons why something is classed as a plant hormone?
- Chemical messenger
- Produced in one part, active elsewhere
- Evokes a change in TARGET cells
- Causes long lasting change
Similarities been circulatory systems of mammals and fish
- Both Closed systems
- Both involve arteries, capillaries, veins
- Both have a heart.
- Both carry O2 using Hb
Differences of circulatory systems of mammals and fish
- Mammals double, fish single
- Mammals 4 heart chambers, fish have 2
- blood pumped at higher pressure in mammals
- Mammals more efficient
- Mammals- 1 set of capil. per pump, fish-2
- Mammals have higher metabolic demand
How is it possible for Acetylcholine to have an effect on skin cells
- Secreted into blood
- Binds to receptors on CSM
- Evokes action of secondary messenger.
Where are Adrenaline and Noradrenaline produced
Adrenal medulla
Function of adrenaline
- Increases HR
- Raises Blood Gluc. levels
(Glycogen –> Glucose)
Function of Noradrenaline
- Increased HR
- Widening pupils
- Widening lung air passages
- Narrowing of blood vessels (Non essential organs). –> High BP
Features of ECTOPIC ECG
Extra Beat, outside of normal rhythm followed by a longer than normal pause before next beat
Features of Atrial fibrillation eCG
Atria and ventricles out of sync:
Rapid atrial contractions, only some passed onto ventricles.
(Many small peaks between each large peak)
Commercial uses of auxins
- Rooting powders- especially in micropropagation
- Weedkillers
- Used in production of seedless fruit.
Commercal uses of Ethene
- Used in the control of ripening
- used to promote fruit dropping
Commercial use of cytokinins
Prevent ageng of ripened fruit and lettuce
Micropropagation to control tissue development
Commercial use of Gibberellins
- Delay ripening and egeing in fruit
- Improve size and shape of fruits
- In Beer brewing to speed up malting
How do erythrocytes respire and why?
Anaerobically- because they do not contain mitochondria
What are the holes in xylem vessels?
Bordered pits: found in unlignified regions.
Allow lateral flow of water- useful e.g. if air bubble forms.
Which muscle type has slow contraction speed?
Smooth muscle
Which muscle type is multinucleate?
Skeletal muscle
Which muscle type has branched and interconnected fibres?
Cardiac muscle
Which muscle type is under conscious control
Skeletal muscle
What are the different sources of ATP during muscle contraction
- Anaerobic respiration
- Aerobic respiration
- Creatine phosphate
Role of glucocorticoids e.g. corticosterone and cortisol
- Regulate the metabolism of carbs
- Regulate BP
- Regulate immune response
What are the risks of using adult stem cells?
- They may have accumulated mutations.
- They may increase cancer risk
What is the concentration between blood and water during countercurrent exchange in fish gills
Constant concentration gradient maintained between blood and water.
What is a limiting factor?
A factor that limits the rate of reaction when it is at low level
What is a sign that data may contain random error?
Large error bars/ high standard deviation
Is the Na+/K+ pump still operating during depolarisation?
Yes
Do somatic and parasympathetic motor neurones use different neurotransmitters?
No
What is the purpose of an unpaired t-test?
It is used to compare the **means **of two samples that are independent of each other. (whether or not the difference in mean is significant)
What can be concluded from a t test result of p< 0.001
- Probability < 0.001
- So differences between means were due to chance
How do you calculate degrees of freedom in a t test?
degrees of freedom =
(n1-1)+(n2-1)
How are sinusoid wall cells adapted for their function?
- Thin cells, so short diffusion distance
- Many fenestrations (pores) which increases permeability
What is the final electron acceptor in the light-dependent stage of photosynthesis?
NADP
Suggest and explain function of DCPIP in hill reaction
- It replaces NADP
- It acts as the final electron acceptor
- It allows photolysis to continue
In hill reaction, boiling test tube means there is no colour change, what does this show?
Shows that proteins/enzymes are needed for the light dependent stage
In hill reaction, why is pellet suspended in buffer solution?
To maintain optimum pH for proteins/enzymes
In Hill reaaction, why was the pellet not suspended in solution containing sucrose?
No need to prevent damage to chloroplasts
Practical precautions when using potometer
- Do not allow air to enter cut shoot- ensure continuous stream of water
- Keep temperature constant- affects rate of tranpiration
- Keep screw clip closed- prevents entry of water whilst measuring
What is the light compensation point?
The point at which photosynthesis and respiration are taking place at the same rate.
