Cytology Quiz

Cytology 1

• There are two main types of cells: prokaryotic cells and eukaryotic cells (human cells).
• Prokaryotic cells are unicellular, have no nucleus, and no organelles.
• Eukaryotic cells are multicellular, form tissues, have a nucleus, and have organelles.
• Eukaryotic cells undergo differentiation, which involves the interaction between genes and microenvironment, leading to two main outcomes: different appearance and structure, and functional specialization.

Nucleus

• The nucleus is the command center of the cell.
• It stores the genetic material, coordinates all cell activities (growth, metabolism, protein synthesis, cell division), and has molecular machinery.
• The nucleus has four components: nuclear envelope, nuclear pores, nucleoplasm, and chromatin.
• The nuclear envelope has two membranes (inner and outer) and a perinuclear space.
• Nuclear pores regulate the movement of ions and small molecules between the nucleoplasm and cytoplasm.
• Nucleoplasm, also known as karyoplasm, is a viscous fluid.
• Chromatin is made up of DNA, with 46 chromosomes in human cells (22 pairs of autosomes in somatic cells, and 22 autosomes in gametes).