dev

• Cleavage Division


  Early cell divisions in the embryo
• Pattern Formation


  Establishing body axes A/P and D/V and coordinating systems
• Morphogenesis


  Shaping the embryo into a 3D form
• Growth


  Increasing cell numbers through multiplication and cell size
• Cell Differentiation


  Cells acquiring specific structures and functions
• Major Questions


  • Development of Specific Cell Types
  • Required Processes During Development
  • Progress in Understanding Human Development
• Development of Specific Cell Types

  • Steps during embryogenesis for cell type formation (e.g., muscle, blood)
  • Control mechanisms like gene expression
• Required Processes During Development

  • Cell-cell communication
  • Cell shape changes, movement, proliferation, and apoptosis
• Progress in Understanding Human Development

  • New imaging technologies (e.g., advanced microscopy)
  • Advances in molecular biology and genetics (e.g., genome sequencing)
  • Ability to manipulate development (e.g., gene/environmental alterations)
  • Use of model organisms (e.g., mouse, frog, fly)
  • Synergy across scientific fields (e.g., physics, mathematics, IT)
  • Communication platforms (e.g., internet resources)
• Cell Function and Attainment

  • A cell is the basic unit of life, attaining specific functions through gene expression and protein synthesis
  • Differentiation and specialization lead to diverse cell types with unique functions
• Visualization of Cells and Tissues

  • Light microscopy
  • Electron microscopy
  • Immunofluorescence
• Histological staining


  Reveals cell structures and tissue organization
• Learning from Other Organisms

  Comparative embryology studies across species reveal evolutionary relationships and fundamental developmental processes
• Cellular Processes in Development

  1. Cell movement and interactions are facilitated by the cytoskeleton, cell adhesion molecules, and the extracellular matrix

  2. Communication between cells through signaling molecules regulates growth and specialization

  
• Embryonic Development


  1. Fertilization marks the beginning, leading to germ layer formation during gastrulation

  2. Gestation involves organogenesis and tissue differentiation

  
• Cell Adhesion and Community Formation

  Cell adhesion molecules mediate tissue formation, supporting growth and development
• Balance of Growth and Death

  Cell proliferation and apoptosis maintain the balance of cell numbers during development
• Tissue Types and Development

  • Epithelial tissue
  • Embryonic stem cells
• Nervous System Development


  1. Notochord and somites guide neural tube formation, critical for brain and spinal cord development

  2. Neural crest cells contribute to diverse cell types in the nervous system

  
• Muscle, Bone, and Connective Tissue

  1. Muscle and bone development involve cell differentiation and tissue organization

  2. Blood vessel development (hematopoiesis) is essential for oxygen transport and immune function
• Germline, Sex Determination, and Meiosis

  Sex determination and meiosis in germ cells establish reproductive potential and genetic diversity
• Experimental Developmental Biology


  • Mouse models
  • Stem cell research
• Developmental disorders


  Result from disruptions in normal developmental processes
• Gestation and Integration of Body Systems

  1. Implantation and placental development support fetal growth and nutrient exchange

  2. Integration of body systems ensures coordinated function for survival and homeostasis
• All organisms are composed of cells
• Cell is the basic unit of life
• Cells are produced by the division of pre-existing cells
• Modern Cell Theory


  • Cells contain hereditary information that can be passed on
  • All cells are essentially comprised of the same chemical mix
  • Cells carry out all basic chemical and physiological processes within themselves
  • Cellular activity depends on subcellular structures' activities
• Why Individual Cells?


  • Efficiency: Increased surface area for nutrient/oxygen supply and waste disposal
  • Specialization: Different cells perform different functions
• Subcellular Compartments and Organelles

  • Plasma Membrane
  • Cilia and Flagella
  • Cytoplasm
  • Mitochondria
  • Endoplasmic Reticulum RER and SER
  • Golgi Apparatus
  • Vacuole
  • Lysosome
  • Peroxisome
  • Nucleus (with nucleoplasm, nuclear envelope, nuclear pores, and nucleolus)
• Cellular Differentiation and Specialization

  • Cells differentiate to perform specific functions
  • Transcriptional control regulates cellular identity and gene expression
  • Transcription factors drive gene expression and cell specialization
  • Master transcription factors regulate critical developmental stages
• Specialized Cell Types


  • Totipotent
  • Pluripotent
  • Multipotent
  • Nullipotent
• Gene expression differences


  Lead to cellular specialization
• Specific genes activated or inactivated for specialized functions
• Red Blood Cells


  Specialized for oxygen transport, lacking a nucleus for increased hemoglobin capacity and flexibility
• Sperm Cells


  Specialized for fertilization, with distinct regions for movement and DNA delivery
• Key Terms/Structures


  • Plasma Membrane
  • Cilia and Flagella
  • Cytoplasm
  • Mitochondria
  • Endoplasmic Reticulum RER and SER
  • Golgi Apparatus
  • Nucleus
  • Transcription Factors
  • Master Transcription Factors

  
• Cells contain hereditary information
• All cells are comprised of the same chemical mix
• Cells carry out basic chemical and physiological processes