Answer:
The arrow is pointing to the "nucleus."
Step-by-step explanation:
A cell is the smallest unit in an organism. It mainly functions to provide structure to the human body, thus it is call "the building blocks of life."
There are 6 organelles in a cell and these are: Nucleus, Ribosomes, Endoplasmic Reticulum, Golgi Aparatus, Chloroplasts and Mitochondria.
The arrow is pointing to the cell's nucleus in the image above. This is an organelle that is enclosed in a membrane. It is where you can find the deoxyribonucleic acid or the DNA, which is essential for hereditary function. It also coordinates activities in the cell, such as metabolism, synthesis of proteins, cell division, etc.
Remember, not all cells have nucleus. Only eukaryotic cells have a nucleus. This cells are considered as more advanced.