The technique used to study the internal structures of cells using electron beams is: MCQ with Answer and Explanation

Explanation:
Transgenic organisms carry a foreign gene (transgene) deliberately inserted into their genome using recombinant DNA technology. Example: transgenic mice with human genes for disease modeling. GMO is broader, but transgenic specifically involves genes from different species. Cloning copies genome, cross-breeding is within species.

Explanation:
The cohesion-tension theory (transpiration pull) is the primary mechanism for water ascent in tall trees. Transpiration creates negative pressure (tension) in leaves, water molecules cohere, and the column is pulled up. Root pressure and capillary action play minor roles. The cohesion of water is due to hydrogen bonds.

Explanation:
Louis Pasteur, through his famous swan-neck flask experiment (1861), demonstrated that life does not arise spontaneously from non-living matter. Sterilized broth in flasks remained sterile unless exposed to airborne microorganisms. Fleming discovered penicillin, Koch established postulates for microbial disease, Jenner developed smallpox vaccine. Pasteur's work was foundational for microbiology.