See for the course of BSc Bio(Hons.) the admission in Lucknow University is strictly based on the merit list. Now in such cases we usually see that the safe score ranges between 80-90%. As you have 72% marks you have less probabilities practically but if you have any kind of reservation like SC,ST etc then you will have an increased chance in getting admission.

Also due to COVID-19 situation an overall hike in the marks achievement by students are hiked. So you can understand that the range of students existing between 80% to 90% have increased. Now as you will take admission in 2021 then the competition will be based on the 2021 students marks achievements. SO overall the competition is increased for you and thus I said a lesser probability.

I hope you get my point. All the very best for your future endeavors!