"Tender green leaves, sorghum beer waste and goat manure" was the winning nutrient mixture, she said.

These are densely covered with stalked mucilagenous and sessile digestive glands, which serve to trap and digest insect prey and absorb the resulting nutrient mixture to supplement their nitrate-low environment.

Maria summoned up a three-dimensional graph, showing population versus time for the full range of nutrient mixtures.

Those tanks, row on row, each contained its little creature floating in a watery fluid of precise composition, infused with a nutrient mixture of ideal proportions.

She has been fed since then with a concentrated nutrient mixture.

Technicians sat at lab benches before petri dishes in which fingernail-size sections of potato stem had been placed in a nutrient mixture.

In-vitro meat can be made by placing a few cells in a nutrient mixture that helps them proliferate.