Biology ISA - Preliminary Investigations

    • Thread Starter

    I'm not sure if I'm allowed to ask this but I'm really confused and I have my Biology ISA section 1 tomorrow so I would be grateful if someone replied. Basically my experiment is basically how the increase in light intensity affects the amount of oxygen produced by pond weed. Basically I thought I understood it, but I was going to just do my experiment in a classroom at room temperature - but in the preliminary investigation my teacher told me to use temperature as my control variable - I don't see how this would be possible as I would have to put the pond weed in a water bath, but how am I supposed to do that while testing the light intensity of the pond weed? I'm really confused haha so I hope someone can help

    You do the preliminary investigation before to work out a suitable range or value to use for the actual experiment. For the ISA, you would do an investigation to find out at what temperature is most suitable to use that doesn't effect the light intensity and what gets reliable results. i am also doing this ISA and we have just been doing about the preliminary experiment! Sorry if it's a bit late! xx

    I am sorry. I have my ISA this week and could you please explain to me what a preliminary investigation is using an example? I am in set 4.
    • Thread Starter

    (Original post by FartWars)
    I am sorry. I have my ISA this week and could you please explain to me what a preliminary investigation is using an example? I am in set 4.
    Preliminary investigations help you find a suitable value for your control variable basically and thet're carried out before your actual experiment; for my preliminary investigation I changed the temperature to see what the optimum temperature was for my experiment. I hope this cleared things up. (:
Write a reply… Reply
Submit reply


Thanks for posting! You just need to create an account in order to submit the post
  1. this can't be left blank
    that username has been taken, please choose another Forgotten your password?
  2. this can't be left blank
    this email is already registered. Forgotten your password?
  3. this can't be left blank

    6 characters or longer with both numbers and letters is safer

  4. this can't be left empty
    your full birthday is required
  1. Oops, you need to agree to our Ts&Cs to register
  2. Slide to join now Processing…

Updated: February 1, 2017
What is stopping you from being in a happy relationship?
Useful resources

Study tools


Essay expert

Learn to write like a pro with our ultimate essay guide.

Thinking about uni already?

Thinking about uni already?

See where you can apply with our uni match tool

Student chat

Ask a question

Chat to other GCSE students and get your study questions answered.


Make study resources

Create all the resources you need to get the grades.


Create your own Study Plan

Organise all your homework and exams so you never miss another deadline.

Resources by subject

From flashcards to mind maps; there's everything you need for all of your GCSE subjects.


Find past papers

100s of GCSE past papers for all your subjects at your fingertips.

Help out other students

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Quick reply
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.