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Biology paper 3

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I am telling you everyone, biology is not like Physics or Chemistry. In Physics in every paper you can see Magnets and Nuclear as the last questions. In Bio, the pattern changes every exam. So you cannot predict what lesson they can ask and what questions.
 
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That's too late xD i took 7 o levels this years ,focused most of it on physics chem and math,i'm learning from past papers for bio since there's no time :p any advice would be appreciated
 
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why dont capillaries have valves? Blood does flow slowly through them to allow efficient diffusion of materials between the capillaries and surrounding tissues, so ??
 
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Also, does the plasma diffuse out of the walls or do they just squeeze through the gaps, just like phagocytes?
 
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aight, somebody lemme know what i have to know about BIOREACTERs and enzymes..
i got A* for my mocks but dont know anything about the working of bioreacters :p
thanks in advance
 
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yep exactly fellow assassin , fermenters ..

Ah basically a frementer is a huge steel tank in which various things are made. Such as alcohol or enzymes.
For example the enzyme penicillin is made from the fungus penicillium. Penicilium is added to the fermenter with glucose and ammonium salts. The glucose provides it with energy for respiration and the ammonium salts are used by it to make amino acids . In a fermenter there are a few things you need to remember.
1. It has a water-cooled jacket to remove heat produced by fermentation.
2. It has a stirrer which keeps the microorganisms suspended so they always have an access to oxygen (it also spreads out the temperature evenly)
3. There are temperature and pH probes which monitor these variables just in case the temperature gets too high or too low, same with pH.
 
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Ah basically a frementer is a huge steel tank in which various things are made. Such as alcohol or enzymes.
For example the enzyme penicillin is made from the fungus penicillium. Penicilium is added to the fermenter with glucose and ammonium salts. The glucose provides it with energy for respiration and the ammonium salts are used by it to make amino acids . In a fermenter there are a few things you need to remember.
1. It has a water-cooled jacket to remove heat produced by fermentation.
2. It has a stirrer which keeps the microorganisms suspended so they always have an access to oxygen (it also spreads out the temperature evenly)
3. There are temperature and pH probes which monitor these variables just in case the temperature gets too high or too low, same with pH.
thanks alot bro :)
 
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what are the implications of self pollination? Cud u guys give me the advantages of cross pollination too?
 
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what are the implications of self pollination? Cud u guys give me the advantages of cross pollination too?
Self Pollination.
-smaller number of pollen grains need to be used as there is a higher chance of successful pollination.(this increases the chance of fertilization andseed formation)
-Less variation in offspring , so self pollinated plants are less likely to cope with adapting to changing environment.

Cross Pollination.

(Advantage)
Increases variation and the ability to adapt to environmental change.
 
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thanks alot bro :)

Anytime x)

what are the implications of self pollination? Cud u guys give me the advantages of cross pollination too?

Implications doesn't mean BAD things. It just means advantages/disadvantages. The implications of self pollination are:
- No pollinating agent is required
- Less variation as there is no exchange of genetic material from different plants
- Is much faster then cross pollination
- Much higher chance of pollination
- Plants are unable to colonize new areas as the pollen grains are not transferred from one plant to the next.

Advantages of cross pollination are:
- Results in variation
- Plants are able to colonize new areas as pollen grains are spread by pollinating agents.
 
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what exactly is negative feedback?

Negative feedback is basically taking neccessary measures to maintain a condition.
Such as body temperature, if it goes higher then normal the brain sends impulses to the sweat glands to produce sweat.
 
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