Saheh's 3/4 question thread

[Daenerys Targaryen]

yeah, i think after they have matured they just sit around in the lymph nodes and do their stuff.

[saheh]

ok so i need a little clarification on primary/secondary hosts?
 
Teacher told us that the primary host is the one in which the parasite is 'born'.. or becomes a gamete or something,, im not too sure
could someone please explain?

Question from A+ practise exams (my attempt at doing a flowchart)
Life cycle of canine heartworm

Microfilariae found in dogs blood       <<<<<<<<<<<<    Adult female produce microfilariae
V                                                                                                      ^
V                                                                                                    ^
Mosquito ingests microfilariae whilst feeding                              Juveniles migrate to heart
V                                                                                                  ^
V                                                                                                  ^
Microfilariae mature into infective juveniles>>>>>>>Introduced to dog when mosquito feeds on dog

Is the primary host the dog?? because thats when the heartworm produces the 'microfilariae'??
and therefore vector is mosquito?

[saheh]

In STAV 07 MC there was a question about radioactively labelling 02 to see where it goes, and the answer is that the O2 would be present in that given off by photosynthesis,
my question is, for aerobic cellular resp. where does the plant get the o2 from? my guess is partly from that from photosynth? does it give off soem into atmosphere, and some into plant??

Thanks!!!
 

[ggxoxo]

In STAV 07 MC there was a question about radioactively labelling 02 to see where it goes, and the answer is that the O2 would be present in that given off by photosynthesis,
my question is, for aerobic cellular resp. where does the plant get the o2 from? my guess is partly from that from photosynth? does it give off soem into atmosphere, and some into plant??

Thanks!!!
 

Yes you're right! It uses some for the plant and some to atmosphre for other organisms to use.

[saheh]

Thanks!
The answer was though that it would be detected in co2 given off by the plant?


another question: what are positive and negative contorls?

[saheh]

What would be a suitable definition of Signal transduction?

i have two and i dont know what is more appropriate:
The process by which a cell converts on kind of signal into another
or (off VCAA 07) Signal transduction refers to the series of events that occur after the receipt of a specific signal, which results in a response.

The word specific is what throws me off. :p thanks all!

[Daenerys Targaryen]

that because, the receptors that receive the stimulus is specific to that signal.

[saheh]

so the second? thanks makes sense


Next question! haha

How do sodium/potassium move into neuron? I have written down (from tsfx 2010) that it is via facilitated diffusion, as they go through channels? (charged ions)

[Daenerys Targaryen]

yeah, facilitated diffusion, they use protein channels.

[saheh]

Thanks yeah makes sense now

Ok another one hehe:
TSFX 2010 mc 15
Endorphins are neurotransmitters which reduce the chances of impuleses travelling along pain pathways to the brain. The ultimate effect of endorphins would be to:
Answer is A Hyperpolarise the membrane of the post-synaptic cell..

Could you or someone explain that, hyperpolarise, ?? Is it like a super action potential?
and then takes longer to come back down?
how does it work in reference to the pain pathways aspect?

[Daenerys Targaryen]

What ive got written in my notes:
The K+ ions leaves the cell and bring the potential back to negative there is an overshot of K+ leaving and this makes the potential more negative than usual. (the dip on the grapgh thing after the high peak). This is called Hyperpolarisation

[saheh]

okeydokey awesome,

so any idea how this would stop pain?

[saheh]

Can phopholipids have saturated+unsaturated tails?

[saheh]

Sorry im totally spamming this

how are prions not denatured when superheated? if they are protein?
 (TSFX multiple choice, that was answer)

[duquesne9995]

prions are heat resistant, apparently don't even get denatured or anything in autoclaving
they're just special and hardcore infectious agents like that

+ sidenote: that's why the prion diseases can be transmitted by usage of surgical instruments because prions aren't going to be destroyed by heat
someone correct me if I'm wrong