Botany

Hey,
After BSc chemistry, you can search for jobs in chemical industries, pharmaceutical companies, industrial units, petrochemical companies, etc. However, if you do not find good opportunities, then I would suggest that you should pursue a Masters in chemistry. If you are interested in teaching, then also there is good scope in the education sector.
Some type of job profiles available for chemistry postgraduates are as follows:
Analytical Chemist
Bio-medical Chemist
Chemical Engineering Associate
Industrial Research Scientist
Lab Chemist
Materials Technologist
Production Chemist
Production Officer
Quality Controller
Different job positions available for graduates after B.Sc. Zoology are listed below:
Animal and Wildlife Educators
Zookeeper
Animal rehabilitator
Zoo Curator
Documentary Maker
Researcher
Animal Behaviorists
Conservationist
Animal Trainers
Forensic Experts
Animal Caretakers
Wildlife Biologists
Animal breeders
Veterinarian
Lab Technicians
Career scope after B.Sc in zoology:
There are lots of job opportunities for graduates in B.Sc. Zoology both in public and private sections. Different employment areas for graduates in B.Sc. Zoology are:
Zoos
Aquariums
Television Channels
Veterinary Hospitals
Animal Clinics
Colleges and Universities
Research
Wildlife Management Firms
Fisheries and Aquaculture
Pest Control Companies
Animal Care-taking Providers
Museums
Botanical Gardens
Conservation organizations
Nature reserves

There are many courses that you can do after your B.Sc. -You can do Masters in any of the subject and start preparing for NET/SLET and become a lecturer in any of the college in India. -If you do not want to do Masters then you can go for B.Ed course and become a teacher and start your career. -You can work for any cement company or any production company as a chemist. -You can also prepare for government. Exam like bank, SSC and start your career. -Higher exam preparation is also an option like IAS, IPS AND IFS. -You can do MBA and start your career as a manager in any of the field you wanted to get in. These are the options available in front of you. Now, to answer your second question; you can do Masters in any other subject after B.Sc. So if you want to go with that then also you can go.

There are better scope in terms of employment if you like to say - then it is undoubtedly chemistry as chemical Industries, Industries based on chemical products worldwide are innumerable and it is increasing. So, there are always requirements of professionals in the chemical domains like paints, polymers, pharmaceuticals, fertilizers etc. Other subjects as you mentioned have opportunity too and may appear boon to individual depending on one's interest and degree of aspiration. Last but not the least, in Education domain, all the subjects require efficient teachers and instructors - and if anyone interested in teaching domain he may feel free to choose a subject based on his interest to give his best output for the development of his Nation based on HR. Best wishes.