(a) Draw a labeled diagram of a simple respirometer suitable for this experiment. (3 marks)
(b) Explain the concept of countercurrent exchange in fish gills and explain why it is more efficient than concurrent flow. (4 marks)
(d) If the experiment used germinating mung beans instead of crickets, how would the results differ? Why? (2 marks)
In Arabidopsis thaliana , flower color is controlled by a single gene with two alleles: Purple (P) dominant over white (p). Another unlinked gene controls leaf shape: Round (R) dominant over pointed (r).
A plant with purple flowers and round leaves (heterozygous for both traits) is self-crossed.
(b) Using a Punnett square or branch diagram, determine the phenotypic ratio of the offspring. (4 marks)
(a) List two structural adaptations of the alveolus that maximize gas exchange. (2 marks)