1. link :https://www.teachers.gov.bd/content/%E0%A6%95%E0%A6%A8%E0%A7%8D%E0%A6%9F%E0%A7%87%E0%A6%A8%E0%A7%8D%E0%A6%9F-%E0%A6%A8%E0%A6%82-%E0%A7%AC%E0%A7%AC-%E0%A6%B8%E0%A6%BE%E0%A6%93%E0%A6%AE-%E2%80%93%E0%A6%87%E0%A6%B8%E0%A6%B2%E0%A6%BE%E0%A6%AE-%E0%A6%93-%E0%A6%A8%E0%A7%88%E0%A6%A4%E0%A6%BF%E0%A6%95-%E0%A6%B6%E0%A6%BF%E0%A6%95%E0%A7%8D%E0%A6%B7%E0%A6%BE-%E2%80%93%E0%A6%B8%E0%A6%AA%E0%A7%8D%E0%A6%A4%E0%A6%AE-%E0%A6%B6%E0%A7%8D%E0%A6%B0%E0%A7%87%E0%A6%A3%E0%A6%BF-%E0%A7%A8%E0%A7%9F-%E0%A6%85%E0%A6%A7%E0%A7%8D%E0%A6%AF%E0%A6%BE%E0%A7%9F-%E0%A6%AA%E0%A6%BE%E0%A6%A0-%E0%A7%AE-%E0%A6%95%E0%A6%A8%E0%A7%8D%E0%A6%9F%E0%A7%87%E0%A6%A8%E0%A7%8D%E0%A6%9F-%E0%A6%A8%E0%A6%BF%E0%A6%B0%E0%A7%8D%E0%A6%AE%E0%A6%BE%E0%A6%A4%E0%A6%BE-link : 2:https://www.teachers.gov.bd/content/%E0%A6%95%E0%A6%A8%E0%A7%8D%E0%A6%9F%E0%A7%87%E0%A6%A8%E0%A7%8D%E0%A6%9F-%E0%A6%A8%E0%A6%82-%E0%A7%AC%E0%A7%AB-%E0%A6%85%E0%A6%AE%E0%A7%87%E0%A6%B0%E0%A7%81%E0%A6%A6%E0%A6%A8%E0%A7%8D%E0%A6%A1%E0%A7%80-%E0%A6%93-%E0%A6%AE%E0%A7%87%E0%A6%B0%E0%A7%81%E0%A6%A6%E0%A6%A8%E0%A7%8D%E0%A6%A1%E0%A7%80-invertebrates-vertebrate-%E0%A6%AA%E0%A7%8D%E0%A6%B0%E0%A6%BE%E0%A6%A3%E0%A7%80%E0%A6%B0-%E0%A6%AA%E0%A6%B0%E0%A6%BF%E0%A6%9A%E0%A6%BF%E0%A6%A4%E0%A6%BF-%E0%A6%93-%E0%A6%AC%E0%A7%88%E0%A6%B6%E0%A6%BF%E0%A6%B7%E0%A7%8D%E0%A6%9F%E0%A7%8D%E0%A6%AF3. link :https://www.teachers.gov.bd/content/shoriful46-%E0%A6%95%E0%A6%A8%E0%A7%8D%E0%A6%9F%E0%A7%87%E0%A6%A8%E0%A7%8D%E0%A6%9F-%E0%A6%A8%E0%A6%82-%E0%A7%AC%E0%A7%AA-blood-cell-%E0%A6%B0%E0%A6%95%E0%A7%8D%E0%A6%A4-%E0%A6%95%E0%A6%A3%E0%A6%BF%E0%A6%95%E0%A6%BE-%E2%80%93%E0%A6%AC%E0%A6%BF%E0%A6%9C%E0%A7%8D%E0%A6%9E%E0%A6%BE%E0%A6%A8-%E0%A7%AF%E0%A6%AE-%E0%A7%A7%E0%A7%A6%E0%A6%AE-%E0%A6%B6%E0%A7%8D%E0%A6%B0%E0%A7%87%E0%A6%A8%E0%A6%BF-%E2%80%93%E0%A6%A4%E0%A7%83%E0%A6%A4%E0%A7%80%E0%A7%9F-%E0%A6%85%E0%A6%A7%E0%A7%8D%E0%A6%AF%E0%A6%BE%E0%A7%9F4. link :https://www.teachers.gov.bd/content/shoriful46-%E0%A6%95%E0%A6%A8%E0%A6%9F%E0%A7%87%E0%A6%A8%E0%A7%8D%E0%A6%9F-%E0%A6%A8%E0%A6%82-63-%E2%80%9C%E0%A6%8F%E0%A6%87%E0%A6%9A%E0%A6%86%E0%A6%87%E0%A6%AD%E0%A6%BF-%E0%A6%8F%E0%A6%87%E0%A6%A1%E0%A6%B8%E2%80%9D-%E0%A7%AF%E0%A6%AE-%E0%A7%A7%E0%A7%A6%E0%A6%AE-%E0%A6%B6%E0%A7%8D%E0%A6%B0%E0%A7%87%E0%A6%A3%E0%A6%BF-%E2%80%93%E0%A6%AC%E0%A6%BE%E0%A6%82%E0%A6%B2%E0%A6%BE%E0%A6%A6%E0%A7%87%E0%A6%B6-%E0%A6%93-%E0%A6%AC%E0%A6%BF%E0%A6%B6%E0%A7%8D%E0%A6%AC%E0%A6%AA%E0%A6%B0%E0%A6%BF%E0%A6%9A%E0%A7%9F%E2%80%93%E0%A6%AE%E0%A7%8B-%E0%A6%B6%E0%A6%B0%E0%A6%BF%E0%A6%AB%E0%A7%81%E0%A6%B2-%E0%A6%87%E0%A6%B8%E0%A6%B2%E0%A6%BE%E0%A6%AE5. link :https://www.teachers.gov.bd/content/%E0%A6%95%E0%A6%A8%E0%A6%9F%E0%A7%87%E0%A6%A8%E0%A7%8D%E0%A6%9F-%E0%A6%A8%E0%A6%82-%E0%A7%AC%E0%A7%A8-%E2%80%9C%E0%A6%AC%E0%A6%BE%E0%A6%82%E0%A6%B2%E0%A6%BE%E0%A6%A6%E0%A7%87%E0%A6%B6%E0%A7%87%E0%A6%B0-%E0%A6%95%E0%A7%8D%E0%A6%B7%E0%A7%81%E0%A6%A6%E0%A7%8D%E0%A6%B0-%E0%A6%9C%E0%A6%BE%E0%A6%A4%E0%A6%BF%E0%A6%B8%E0%A6%A4%E0%A7%8D%E0%A6%A4%E0%A6%BE%E2%80%9D-%E0%A6%AE%E0%A6%BE%E0%A6%B0%E0%A6%AE%E0%A6%BE-%E0%A6%B8%E0%A6%AE%E0%A7%8D%E0%A6%AA%E0%A7%8D%E0%A6%B0%E0%A6%A6%E0%A6%BE%E0%A7%9F-%E0%A7%AD%E0%A6%AE-%E0%A6%B6%E0%A7%8D%E0%A6%B0%E0%A7%87%E0%A6%A3%E0%A6%BF-%E2%80%93%E0%A6%AC%E0%A6%BE%E0%A6%82%E0%A6%B2%E0%A6%BE-%E0%A7%A7%E0%A6%AE-%E0%A6%AA%E0%A6%A4%E0%A7%8D%E0%A6%B0