The main differences between emitter and collector are doping concentration and size. The emitter is heavily doped, while the collector is lightly doped. You could try to swap them, but you'll get a very low \$H_{FE}\$, probably even less than 1.
Image Credit: Photo: Oxmoor House. SEASON: Although available year-round, eggplant is at its peak from July to October. CHOOSING: When selecting, look for eggplants with firm, glossy skin. Size and color vary widely among types, but the eggplant should feel heavy. Avoid those with wrinkled skin, soft spots, or brown patches.
Growing From Seed. Because eggplants require a relatively long time to mature and will not thrive in cool weather, if you plan to grow your eggplants from seed, you will need to begin them indoors, about eight to 10 weeks before the average last frost date for your region. Seeds need warm soil to germinate and for the seedlings to grow quickly. The ideal soil temperature for germination is between 70 and 90 degrees Fahrenheit, so be sure to keep your seedlings in a warm location in your home or use a heating mat to warm the soil.