A plasmid used as a cloning vector must have: MCQ with Answer and Explanation

Explanation:
The epidermis is the avascular, outermost layer of skin, composed mainly of keratinized stratified squamous epithelium. It provides a waterproof barrier and creates skin tone via melanocytes. The dermis is below, containing vessels and nerves, hypodermis is subcutaneous fat, endodermis is a root layer in plants.

Explanation:
Agrobacterium tumefaciens is a soil bacterium that naturally transfers a segment of its Ti plasmid into plant cells, making it a natural genetic engineer used to create transgenic plants. RNA interference (RNAi) is a cellular defense mechanism used in biotechnology to silence specific mRNA molecules, preventing gene expression. Bt toxin is inactive in the insect gut until it encounters the alkaline pH, which solubilizes and activates it. Thus, statements 1 and 3 are correct.

Explanation:
The pitcher plant is an insectivorous (carnivorous) plant. Its leaves are modified into pitcher-shaped structures to trap and digest insects. This adaptation is primarily to supplement the plant's nitrogen intake, as it typically grows in nitrogen-deficient soils (like bogs). The digested insects provide essential nitrogenous compounds.