Cell Biology: Nucleus and Cytoskeleton

Nucleic Acids and DNA Structure

• The main function of nucleic acids is to store and transmit genetic information.
• A nucleotide is distinct due to its three components: a sugar molecule, a phosphate group, and a nitrogenous base.
• The DNA structure is described as a double helix, where two complementary strands are twisted together with sugar and phosphate molecules making up the backbone, and nitrogenous bases projecting inward from the backbone.

Cell Organelles and Functions

• Organelles are found within eukaryotic cells, which are cells with a true nucleus.
• The function of the cell membrane is to regulate the movement of substances in and out of the cell.
• The heads of phospholipids are made of hydrophilic (water-loving) phosphate groups.

Cellular Control and Energy Generation

• The nucleus is the organelle that controls the normal activities of the cell.
• The mitochondria is the organelle responsible for generating cellular energy in the form of ATP (adenosine triphosphate).

Cellular Functions and Division

• The function of the nucleolus in the cell is to synthesize and assemble ribosomes.
• The spindle fibers are the organelle involved in pulling chromosome pairs apart during cell division.