Dr. marshall demonstrated that gastric ulcers are caused by a bacterium by using

Dr. marshall demonstrated that gastric ulcers are caused by a bacterium by using Koch’s postulates.

Koch’s postulates are four standards created to confirm a causative relationship between a microorganism and a disease. Koch’s postulates were formulated in 1884 by Robert Koch and Friedrich Loeffler.  Koch’s postulates include;

the microorganism must be found in every cases of the disease. the microorganism must be isolated from the diseased host and grown in pure culture .the cultured microorganism must cause the disease when introduced into a healthy laboratory animal .the microorganism must be re-isolated from the new host and identified to be the same as the original causative agent .

Schools are being forced to embrace computers. unlike their "digital immigrant" teachers, these students are "digital natives", born into a world where technology is an integral part of everyday life. almost every student has access to a multitude of computers, laptops and tablet devices. it would be crazy to assume an assignment would  notbe written on computer in this day and age.many schools now have a 1-to-1 computer policy, and many districts and states in the united states have mandated computers or ipads across the state for every student,  including los angeles, the second largest school district in the country.but the thing is, when they tried it in la, it wasn't the success they hoped for. that's because the tablets weren't used as much as they expected. rather, it appeared there was a gap between the digital native's love of technology and their use of it in the classroom.this conflicted relationship with computers is also underscored by much of the literature on education. it is also highlighted in professional development and conferences such as  edutech.

Very hard to understand