Identify the organelles that are present and try to deduce the function of cell.
The black blobs could be vacuoles. Vacuoles are used for storing substances within the cell. Vacuoles store food or a variety of nutrients that the cell may need to survive. They are also often associated with transport of various substances within the cell.
The oblong-shaped organelle on the bottom of the cell looks like a mitochondrion. Mitochondria are often referred to as the "power-houses" of the cell. This is where cellular respiration occurs and energy, in the form of ATP, is produced.
Lastly, the large, central organelle is the nucleus, with the smaller nucleolus inside. The nucleus is the control center of the cell and where DNA is located. The black dots covering this organelle are likely ribosomes on the nuclear envelope, which play a role in protein synthesis in the cell.