1. The Nucleus

2. Spherical or Oval Structure Spherical or Oval Structure Usually most predominant structure in a cell Usually most predominant structure in a cell Most cells have a single nucleus Most cells have a single nucleus Mature RBCs – no nuclesu Mature RBCs – no nuclesu Skeletal Muscle – multinucleated Skeletal Muscle – multinucleated

3. Nuclear Envelope Double Membrane Double Membrane Lipid Bilayers Lipid Bilayers Separates the Nucleus from the Cytoplasm Separates the Nucleus from the Cytoplasm Outer membrane is continuous with the Rough ER Outer membrane is continuous with the Rough ER

4. Nuclear Pores Openings in the nuclear envelope Openings in the nuclear envelope Control movement of substances between the nucleus and cytoplasm Control movement of substances between the nucleus and cytoplasm

5. Nucleoli Cluster of protein, DNA and RNA Cluster of protein, DNA and RNA Found within the nucleus Found within the nucleus Site of ribosome production Site of ribosome production Cells that produce large amounts of protein have very predominant nucleoli Cells that produce large amounts of protein have very predominant nucleoli

7. Genes Heredity Units Heredity Units Control cell structure and direct cell activity Control cell structure and direct cell activity Arranged in single file on chromosomes Arranged in single file on chromosomes Humans cells have 46 chromosomes Humans cells have 46 chromosomes Appear as thin threads called chromatin when the cell isn’t dividing Appear as thin threads called chromatin when the cell isn’t dividing

10. Genome The total genetic information carried in a cell or organism The total genetic information carried in a cell or organism Genomics – the study of the genome and the biological functions of the organism Genomics – the study of the genome and the biological functions of the organism

11. Human Genome Project Began in 1990 in an effort to sequence all 3.2 billion (BILLION!) nucleotides of the human genome. Began in 1990 in an effort to sequence all 3.2 billion (BILLION!) nucleotides of the human genome.

13. Checkpoint Describe the function of the nucleus Describe the function of the nucleus What are the structures that compose the nucleus? What are the structures that compose the nucleus? Do all cells have a single nucleus? Do all cells have a single nucleus?