Homeostasis & Feedback Mechanisms (1 Viewer)

[asl2]

Hey ppl... I was going through the Biology Independent HSC Trial 2002...could you please tell me if this is the right response?

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Q19. Describe Homeostasis (1 Mark)

Homeostasis is the process by which organisms maintain a constant internal body temperature. Such as maintaining a stable internal body temperature of 37 in mammals.

b. Explain using an example, the TWO stages of homeostasis (2 marks)

The process of homeostasis consistes of two stages. Detecting the change and counteracting the change, both of which are part of the Nervous System. Normal body temperature -> increase detected ->hypothalmus initates cooling mechanism -> sweating, blood vessel dilation -> temperature falls -> normal body temperature.

20. Explain the requirement for feedback mechanism in organisms. Illustrate your answer with a specific example that identifies the relevant stimuli and responses and any receptors and effectors involved. ( 3 Marks)

A feedback mechanism regulates and maintains balance or homeostasis, it is required so that the body can interact with internal / external environmetns. If the internal body temperature rises, the change is detected by min-alignment receptors which signal the hypothalmus which then signals the hypothalmus which then signals the effectors (muscles & glands) to start sweating, decrease body metabolism and to dialate blood vessels by doing this, the body temperature drops to the optimum level of 37.
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I'm not too sure about the examples I've used...

Thanks
Ajit

 

[honky tonk]

I would have talked more about the Detecting and Counteracting of homeostasis, like gone into specifics and stuff. Everything else looks good though.

 

[asl2]

can u plz give me some better examples?

 

[Hannah]

Q19: "Homeostasis is the process by which organisms maintain a relatively constant or stable internal environment." [NOTE: homeostasis is not just temperature regulation, it's internal environment regulation]
Leave off the mammal example - it's a waste of time because it's not asked for and it won't get you extra marks - the examiners will skip right over it as irrelevant information.

b: "both of which are part of the nervous system" sounds weird... but maybe that's just me...
Before you use the temperature example, make sure to say "for example, with temperature regulation," then do your example, because you make it out as though temperature is the only thing homeostasis effects.

20: again, make sure, before your example, you say "for example", because the feedback mechanism can also work the other way (shivering instead of sweating)

Other than that - your answers are good.

 

[asl2]

thanks guys