2002 HSC Question 28... (1 Viewer)

[schooly]

Hi there, i was doing the 2002 biology hsc paper Q28 (Communication) and the last question there :

(d) The light signal reaching the retina is transformed into electrochemical signals. Describe the different structures and processes in the retina that can achieve the energy transformation described above.
(7 marks)

i dont know where to start and what exactly it is i need to write. does anyone here have an answer to this or can put in some tips/suggestions would be appreciated.

P.S. i wasnt able to find answers to these papers anywhere. so if anyone has or knows where to get would also be nice.

Thankyou

 

[babydoll_]

Mod to the rescue
I'll just type the answer from Success One:

Th retina contains two different types of photoreceptor cells - the rods and the cones. They each contain different pigments that enable them to absorb different wavelengths of light. There are three different types of cone cells each responding to three colour wavelengths: red, blue and green. They are unable to detect these wavelengths under low light intensities. The rods are scattered around the perimeter of the retina and are sensitive to light intensity, but are not sensitive to colours.

The visual pigments absorb light and change their structure resulting in an action potential variance. In this way, the light detected is changed into an electrochemical message that is transferred to the brain via the optic nerve.

it makes sense to me.. do you want me to explain anything?

 

[schooly]

I'll just type the answer from Success One

does success one have answers to the hsc papers?

na answer seems okay , no need to explain .

but seems a bit too short/brief for 7 marks ey?

 

[babydoll_]

well i guess its short and concise eh

it has answers to 2001 and 2002... the new version does at least