Valves, they are like flaps of muscle that keeps the blood in its place util its ready to be pumped along.
1- The average temperature in tropical rainforests ranges from 70 to 85°F (21 to 30°C). The environment is pretty wet in tropical rainforests, maintaining a high humidity of 77% to 88% year-round.
2- The tropical rainforest biome has four main characteristics: very high annual rainfall, high average temperatures, nutrient-poor soil, and high levels of biodiversity (species richness). Rainfall: The word “rainforest” implies that these are the some of the world's wettest ecosystems.
3- plants : orchids, cacao trees, peace lilies
birds of paradise.
animals: frogs, salamanders, snakes, jaguars, kinkajous, lemurs.
B because when the positive feedback happens it increases the temperature and when the negative feedback occurs the temperature lowers itself
Celluar respiration breaks down glucose and photosynthesis makes glucose.
