Histology Cell Cycle Quiz

Cell Structure

• Basic unit of life, composed of various parts each with specific functions.

Parts of the Cell

• Cell Membrane (Plasma Membrane)

  • Regulates entry and exit of molecules.

• Nucleus

  • Central structure with a double membrane enclosing nuclear pores.
  • Contains chromatin (DNA and proteins) with a nucleolus that produces ribosomal subunits.

• Cytoplasm

  • Semifluid substance between cell membrane and nuclear membrane containing organelles.

Organelles and Their Functions

• Ribosomes

  • Site of protein synthesis.

• Endoplasmic Reticulum (ER)

  • Rough ER (RER): Studded with ribosomes, involved in protein processing.
  • Smooth ER (SER): Lacks ribosomes, involved in lipid processing and detoxification.

• Mitochondria

  • Known as the "powerhouse," responsible for ATP production via cellular respiration.

• Lysosomes

  • Digestive enzymes for breaking down macromolecules.

• Golgi Apparatus

  • Modifies, packages, and secretes cell products.

• Peroxisomes

  • Involved in oxidative processes.

• Cytoskeleton

  • Composed of microtubules, intermediate filaments, and actin filaments; provides structure and facilitates movement.

• Centrioles

  • Assist in cell division.

• Cilia

  • Motile projections that aid in movement.

• Filaments

  • Provide shape and mechanical strength to cells.

Inclusions (Non-Living Components)

• Nutritive Substances

  • Includes carbohydrates, fats, and proteins.

• Pigment Granules

  • Example: Melanin, involved in coloration.

• Vacuoles

  • Storage cavities within the cell.

• Foreign Substances

  • Engulfed by macrophages.

Cell Cycle

• Process through which a cell divides to form two new cells, consisting of stages: G1, S, G2, and M.

• G1 Stage

  • Preparatory phase for cell division.

• S Phase

  • DNA synthesis occurs, duplicating genetic material.

• G2 Stage

  • Organizes and condenses genetic material in preparation for division.

• M Phase

  • Mitosis takes place where genetic material is distributed into daughter cells.

Nucleus

• Largest organelle directing protein synthesis.
• Contains nuclear membrane, nucleolus, and chromatin.

Plasma Membrane

• Envelops the cell and maintains structural integrity known as plasmalemma.

Mitosis Stages

• Prophase: Nucleolus and nuclear envelope disappear.
• Prometaphase: Nuclear envelope fully disappears.
• Metaphase: Chromosomes align at the equatorial plate.
• Anaphase: Chromatids move to opposite poles.
• Telophase: Nuclear envelope and nucleoli reform.

Common Diseases

• Down Syndrome (Trisomy 21)

  • Resulting from nondisjunction of chromosomes; characterized by mental retardation and short stature.

• Malignant Tumors (Cancer)

  • Characterized by enlarged, abnormally shaped nuclei with dark staining.

Test your knowledge on histology and the cell cycle with this quiz. Explore the roles of various cellular structures, including filaments and inclusions, and understand their importance in maintaining cell shape and function. Perfect for students studying histology or related fields.