Which organism(s) came first on your timeline? Explain the importance of the organism(s) and why you chose to place the organism(s) first on your timeline:

dna is made up of six smaller molecules -- a five carbon sugar called deoxyribose, a phosphate molecule and four different nitrogenous bases (adenine, thymine, cytosine and guanine).

the most common type of reef is the fringing reef. this type of reef grows seaward directly from the shore. they form borders along the shoreline and surrounding islands.

the circled areas are referred to   as sunspots.   the sunspots are cooler than the   surrounding area.

sunspots are temporary phenomena on the photosphere of the sun that appear visibly as dark spots compared to surrounding regions. they correspond to concentrations of magnetic field flux that inhibit convection and result in reduced surface temperature compared to the surrounding photosphere.

producers within ecosystems are essential as they are at the base of the food chain. plants are examples of producers. they use the process of photosynthesis to capture light energy and use it to convert simple inorganic substances (carbon dioxide and water) into organic substances (glucose).