The tallest artificial structure is Burj Khalifa, a skyscraper in Dubai that reached 829.8 m (2,722 ft) in height on January 17, 2009. By April 7, 2008 it had been built higher than the KVLY-TV mast in North Dakota, USA.
The nucleolus is a round body located inside the nucleus of a eukaryotic cell. It is not surrounded by a membrane but sits in the nucleus. The nucleolus makes ribosomal subunits from proteins and ribosomal RNA, also known as rRNA. It then sends the subunits out to the rest of the cell where they combine into complete ribosomes.
Plant Cell Nucleus The nucleus is a highly specialized organelle that serves as the information and administrative center of the cell. This organelle has two major functions.ucleolus-The nucleolus is a membrane-less organelle within the nucleus that manufactures ribosomes, the cell's protein-producing structures. Through the microscope, the nucleolus looks like a large dark spot within the nucleus.