Histology: The Cell PDF

HISTOLOGY || The Cell Dr. Antoinette Leuterio CELL - Basic structural and functional unit Parts of the Cell: 1. Cell Membrane  aka plasma membrane  outer surface that regulates the ENTRANCE and EXIT of molecules. 2. Nucleus  Almost located at the...

HISTOLOGY || The Cell Dr. Antoinette Leuterio CELL - Basic structural and functional unit Parts of the Cell: 1. Cell Membrane  aka plasma membrane  outer surface that regulates the ENTRANCE and EXIT of molecules. 2. Nucleus  Almost located at the center of the cell.  Has a nuclear membrane  Is a double membrane with nuclear pores that encloses the nucleus.  Contains chromatin which contains DNA and CHON  Inside the nucleus, nucleolus can be ORGANELLES (Functions) found which produces subunits of ribosomes. 1. Ribosomes 3. Cytoplasm  CHON synthesis  Semifluid substance of a cell external 2. ER (RER/SER) to nuclear membrane and internal to  Detoxify substances cell membrane. 3. Mitochondria Cytoskeleton: Microtubules,  “powerhouse” Intermediate filaments and Actin 4. Lysosomes filaments they maintain cell shape  Digestive apparatus and assist movement of the cell 5. Golgi Apparatus parts.  Site for concentrating CHONs Lysosome: digests macromolecules 6. Peroxisomes Golgi Apparatus: processes,  Oxidative processes packages, and secretes modified 7. Microtubules cell products.  For cell division and maintain cell Mitochondrion: carries a cellular shape respiration, producing ATP 8. Centrioles molecules  For cell division Endoplasmic Reticulum: 9. Cilia ▪ RER: with ribosomes,  Motile projections processes CHON 10. Filaments ▪ SER: lacks ribosomes,  Maintain shape of cell and provide processes LIPID mechanical strength to cells. MOLECULES. SLG || ASTRAEA HISTOLOGY || 1A CELL CYCLE INCLUSIONS (NON-LIVING) - Cell Cycle 1. Nutritive Substances  The process through which cell a. CHO replicate and make two new cells b. FAT - Cell cycle has different stages c. CHON  G1, S, G2, and M 2. PIGMENT GRANULES - G1  Melanin  The cell is preparing to divide. 3. VACUOLES - S Phase  Storage cavities  The cell copies all the DNA (S stands 4. FOREIGN SUBSTANCES for DNA synthesis)  Phagocytose by macrophages - G2 stage  It organizes and condenses the genetic material, or starts to condense the CYTOPLASM genetic material, and prepares to - 3 main components: divide. 1. Organelles – active units - M 2. Inclusions  M stands for MITOSIS 3. Cytoskeleton  The cell actually partitions the two copies of the genetic material into the two daughter cells. NUCLEUS - AFTER M phase completes, cell division - Largest organelle of the cell occurs and two cells are left and the cell - Includes nuclear membrane, nucleolus, cycle can begin again. nucleoplasm, chromatin - Directs CHON synthesis in the cytoplasm - Command center of the cell PLASMA MEMBRANE - Plasmalemma - Cell membrane - Envelops the cell and maintain its structural integrity SLG || ASTRAEA HISTOLOGY || 1A MITOSIS 1. PROPHASE MITOSIS vs MEIOSIS  START of the stage  Nucleolus and nuclear envelope disappear 2. PROMETAPHASE  Nuclear envelope disappears 3. METAPHASE  Chromosomes aligned at equatorial plate  Chromosomes will meet or align at the center 4. ANAPHASE  Chromatids separate to move to opposite poles 5. TELOPHASE  Reformation of nuclear envelope and nucleoli Common Diseases - Down Syndrome (trisomy 21)  Due to nondisjunction of chromosomes characterized by mental retardation and short stature. - Malignant tumors (cancer)  Nuclei of the cells are often enlarged, abnormally shaped and extremely dark staining. SLG || ASTRAEA HISTOLOGY || 1A SLG || ASTRAEA