HSC Biology Marathon 2015 (1 Viewer)

[BlueGas]

Help someone. Why is the answer C not A.

Ah I remember a similar question I had for my first topic test of maintaining a balance lol, anyway, when a person's body is dehydrated, there is a decrease in water and an increase of salt, hence why both aldosterone and ADH are needed.

 

[Flop21]

Help someone. Why is the answer C not A.

This tripped me up as well. I would like to know also.

But I'm thinking, because he's dehydrated > high salt concentrated blood / low water. So my initial thought is A. But they say it's C, so maybe because he's just ran a race, his salts are also low (as they've been sweated out), so both are released.

Is this right or is there another reason?

 

[Flop21]

Because ADH does not control the levels of salt in the blood. It only controls the concentration of salt through water retention. (Usually because of dehydration)
It makes collecting ducts more permeable so that water can be reabsorbed back into the blood and body tissues.

And when aldosterone is released, there is more sodium absorbed which leads to more water returning to the blood (in order to complement the salt and retain normal levels)

They work off each other

So when water is needed, both hormones are released??

 

[BlueGas]

This tripped me up as well. I would like to know also.

But I'm thinking, because he's dehydrated > high salt concentrated blood / low water. So my initial thought is A. But they say it's C, so maybe because he's just ran a race, his salts are also low (as they've been sweated out), so both are released.

Is this right or is there another reason?

Oh I thought that salt levels are high, true, sweat contains salt and water lol.

 

[BlueGas]

So when water is needed, both hormones are released??

The person after the marathon released sweat, which is salt and water, basically resulting in dehydration. To return water levels to normal, ADH is released, and to return salt levels to normal, aldosterone is released.

 

[Flop21]

The person after the marathon released sweat, which is salt and water, basically resulting in dehydration. To return water levels to normal, ADH is released, and to return salt levels to normal, aldosterone is released.

Okay sweet this makes sense. All the kidney stuff confuses me a bit but I think I've got a basic understanding of it now.

 

[tfw english]

So when water is needed, both hormones are released??

I'm not too sure? Maybe someone knows it better, but it's tricky so some clarification would be good.

I know that aldosterone occurs in the nephrons and ADH in the collecting ducts and distal tubules, so ADH would generally occur after aldosterone. Because the initial level of water in the filtered blood is decided by aldosterone (less/more diffusing in), then the ADH would decide whether the water is needed, and therefore the concentration of urine and how it maintains the concentration.

I'm not sure if I actually made any sense, my brain is starting to scramble haha, hopefully someone else can help

EDIT: Nvm, BlueGas strikes again

 

[Flop21]

Outline the work of Beadle and Tatum and their findings (3 marks).

 

[Flop21]

Outline the historical development of our understanding of the cause and prevention of malaria (3 marks).

 

[tfw english]

Explain, using specific examples, the importance of correct sensory signals by the brain for the coordination of animal behavior. (4)

 

[DepressedPenguino]

True, although the temporal lobe processes speech in Wernicke's area

Hmm that in the parietal lobe (off the top of my head)

 

[DepressedPenguino]

^ not in the temporal lobe.

 

[tfw english]

Outline the historical development of our understanding of the cause and prevention of malaria (3 marks).

In 1880, Charles Laveran observed micro-organisms in fresh blood from malarial patients and that malaria was caused by the plasmodium micro-organisms. Later in the century, Patrick Manson proposed that malaria is transmitted by mosquitoes, Ronald Ross added to this as he established that the protozoan Plasmodium was the cause of malaria, he showed it can be transmitted and thus established the cycle of transmission through experiments with mosquitoes and birds. These understandings have led to development of treatments of malaria including quinine and chloroquinine as we have been able to understand the transmission and the pathogenic nature of the disease

 

[DepressedPenguino]

So when water is needed, both hormones are released??

Yeah i am pretty sure. Also, two years ago, i heard from a lecture that neither adh or aldoaterone are ceased to release. Perhaps that is uni bio tho

 

[DepressedPenguino]

In 1880, Charles Laveran observed micro-organisms in fresh blood from malarial patients and that malaria was caused by the plasmodium micro-organisms. Later in the century, Patrick Manson proposed that malaria is transmitted by mosquitoes, Ronald Ross added to this as he established that the protozoan Plasmodium was the cause of malaria, he showed it can be transmitted and thus established the cycle of transmission through experiments with mosquitoes and birds. These understandings have led to development of treatments of malaria including quinine and chloroquinine as we have been able to understand the transmission and the pathogenic nature of the disease

Quinine and chloroquine was developed prior the full understanding of all the stages of the Anopheles mosquito's life cycle.

 

[tfw english]

Quinine and chloroquine was developed prior the full understanding of all the stages of the Anopheles mosquito's life cycle.

fek

Welp, back I go

 

[Flop21]

When are you guys finishing studying bio?

 

[Queenroot]

Because ADH does not control the levels of salt in the blood. It only controls the concentration of salt through water retention. (Usually because of dehydration)
It makes collecting ducts more permeable so that water can be reabsorbed back into the blood and body tissues.

And when aldosterone is released, there is more sodium absorbed which leads to more water returning to the blood (in order to complement the salt and retain normal levels)

They work off each other

You are right, that is why both ADH and adolsterone are released.

 

[Queenroot]

So when water is needed, both hormones are released??

Yes

 

[DepressedPenguino]

When are you guys finishing studying bio?

After trials i havent touched my bio notes haha but i will probably stay up all night tonight just to revise :^/