CAIE A-Level Biology A2 16.2.5 Gibberellin Role in Stem Elongation Questions

any three from:

1 lele is, homozygous recessive / two recessive alleles ;

2 le (allele)/lele, codes for a non-functional enzyme ;

3 no, active gibberellin / $\mathrm{GA}_{1}$

or

ref. to gibberellin inactive ;

4 no / less, cell elongation

or no / less, stem elongation / increase in internodal length ;

5 AVP ;
e.g. ref. to GA $3 \beta$-hydroxylase / GA3-oxidase / last enzyme in the pathway that produces, active gibberellin / $\mathrm{GA}_{1}$ le allele codes for alanine instead of threonine (in the enzyme)