Rachel Correct and thanks.
Sustainability (2025)For Question 12, is the justification that 'iii Replication of DNA' is not one of the answers that it is in interphase rather than the stages of Mitosis/meiosis?
Mock exam - paper 1a HL - Model answersDear Fred, thanks for your comment. I have spent a couple of days wrestling with the best way to illustrate these concepts and I have just posted the new activity this afternoon. Best wishes, David
C1.2 Cell Respiration - planning sheetThe sheet is on the old scheme also so there is a markscheme in the archive here https://thinkib.net/biology/page/27644/conserving-fish-stocks-model-answers
Sustainability (2025)Yes, please provide model answers
HL Examples of adaptationsCan you please add the model answers for the cyclic succession? Thank you so very much
Succession (2025)My understanding is that this is for a re-grade, and scores can go down more when this happens. We just want to have the annotated comments on each report that teachers must provide to see where the original scores came from.
Dissection of an example investigation (IA)I completely agree and wish there was an answer to this
Dissection of an example investigation (IA)I've noticed that two of these EE use saliva, but the use of any bodily fluids is forbidden under the animal experimentation policy. Perhaps the rules were different when these were conducted?
Extended Essay titles and research questions
Kristaps
Hello, My students noticed that the proposed silent mutation in the presentation of Activity 1 does, in fact, change the amino acid (ATG to AGG --> UAC to UCC --> Tyr to Ser). Mutation ATG --> ATA would work here (ATA --> UAU -->...
Types of mutation (2025)