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Difference between saprobionts and detrivores

Hi i was wondering what the difference between the two are.

From my understanding, in both the Carbon and Nitrogen cycle:

Detrivores break down (hydrolyse) long chain polymers.
Then Sapobionts digest these shorter chain via extra cellular digestion.
The resulting ammonia (in nitrogen cycle) becomes ammonium ions in the soil.
The carbon is absorbed by the saprobionts and released via aerobic respiration as CO2.

However on markschemes, there is no mention of detrivores. So is my understanding wrong? What exactly are detrivores?

Thanks
Reply 1
Original post by user1-4
Hi i was wondering what the difference between the two are.

From my understanding, in both the Carbon and Nitrogen cycle:

Detrivores break down (hydrolyse) long chain polymers.
Then Sapobionts digest these shorter chain via extra cellular digestion.
The resulting ammonia (in nitrogen cycle) becomes ammonium ions in the soil.
The carbon is absorbed by the saprobionts and released via aerobic respiration as CO2.

However on markschemes, there is no mention of detrivores. So is my understanding wrong? What exactly are detrivores?

Thanks


Saprobionts digest molecules via extracellular digestion, as you say.

Detrivores digest any organic matter as it is (they don't secrete enzymes and absorb the soluble products), and actually kinda help the saprobionts. They physically break up large pieces of plant tissue (e.g. leaves), and egest them as faeces, which have a greater surface area for the saprobionts to work on. Detrivores also aerate the soil, to provide a good oxygen supply for the saprobionts to respire aerobically, and also secrete minerals such as urea, which are useful for the saprobionts.

I do AQA Biology but I don't remember that being part of the course - that's just part of things 'beyond the course' for the essay at the end of the exam...that's going to be great fun :mad:

Hope that helps :smile:
Reply 2
Original post by Tappouni
Saprobionts digest molecules via extracellular digestion, as you say.

Detrivores digest any organic matter as it is (they don't secrete enzymes and absorb the soluble products), and actually kinda help the saprobionts. They physically break up large pieces of plant tissue (e.g. leaves), and egest them as faeces, which have a greater surface area for the saprobionts to work on. Detrivores also aerate the soil, to provide a good oxygen supply for the saprobionts to respire aerobically, and also secrete minerals such as urea, which are useful for the saprobionts.

I do AQA Biology but I don't remember that being part of the course - that's just part of things 'beyond the course' for the essay at the end of the exam...that's going to be great fun :mad:

Hope that helps :smile:


oh alright thanks. Didnt realise that wasnt part of our spec.

Are you going to prepare for the essay? I'm just going to try and get good on the exam part, the essay I will treat as a a little bonus (couple extra marks out of the 25) for when i've checked all my answers. We can lose like 30 marks and get an A* I think.
Reply 3
Original post by user1-4
oh alright thanks. Didnt realise that wasnt part of our spec.

Are you going to prepare for the essay? I'm just going to try and get good on the exam part, the essay I will treat as a a little bonus (couple extra marks out of the 25) for when i've checked all my answers. We can lose like 30 marks and get an A* I think.


We haven't gone over it, and I haven't seen a mention of detrivores in the AQA book, so I'm assuming it's not actually in there?

Well as a class we all had to pick an AS and A2 topic, and write a short paragraph on something relating to that topic 'beyond the course', so we had a list compiled (from those that could be bothered to do it :tongue:) Me personally, I'm just trying to remember AS stuff too, as it's a synoptic essay, though I'm sure I can pluck up enough stuff to get a decent-ish mark :smile:

Yeah the June 2013 one had really low boundaries - 67/100 for an A*! But in June 2012, it was 76/100, so that's quite a bit of a difference :s-smilie:

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