The greenhouse effect is the trapping of a stars warmth in the lower atmosphere of a planet by gasses in the air trapping the energy. This is similar to what actual greenhouses do, where they trap the warmth and humidity of the air inside it so plants can flourish. Farm animals produce a huge amount of the greenhouse gasses required for our planet to trap the suns warmth.
The correct answer is chloroplast. If an organism has chloroplasts then it will be an autotroph because it will be able to make its own food by the means of photosynthesis. This is common for plants but there are some bacteria that can photosynthesize as well. If you don't have them you have to feed on other organisms that have energy for you.
Answer:
A portion of the Earth's atmosphere that protects the Earth from radiation