Microscopes and Cell Theory

Cell Cycle

• Cell grows, duplicates its DNA, and gets ready for division
• G₁ phase: Growth and organelle production
• S phase: DNA replication
• G₂ phase: Final preparations
• Mitotic (M) phase: The actual division process
• Mitosis: Dividing the DNA into two sets
• Prophase: Chromosomes condense
• Metaphase: Chromosomes line up
• Anaphase: Sister chromatids separate
• Telophase: New nuclear envelopes form
• Cytokinesis: Splitting the cell into two daughter cells
• G₀ phase: Some cells rest and don’t divide

Types of Stem Cells

• Totipotent stem cells: Can differentiate into any cell type required for the development of a complete organism
• Pluripotent stem cells: Can differentiate into all of the cells of the adult body
• Multipotent stem cells: Can differentiate into a limited range of cell types
• Oligopotent stem cells: Can differentiate into a few closely related cell types
• Unipotent stem cells: Can only differentiate into one cell type

Plant Organ Systems

• Meristematic Tissue: Cells that keep dividing and help the plant grow
• Apical Meristems: At the tips of stems and roots, they make the plant longer
• Lateral Meristems: Make the plant thicker as it grows
• Intercalary Meristems: Found in some plants, they allow for elongation even after cutting
• Permanent Tissue: Cells have specific jobs and don’t divide anymore
• Dermal Tissue: Covers and protects the plant
• Vascular Tissue: Moves water, nutrients, and sugars around
• Ground Tissue: Supports the plant, stores stuff, and helps with photosynthesis
• Shoot System: Aboveground parts like stems, leaves, flowers, and fruits
• Root System: Underground, supporting the plant

Types of Roots

• Tap Root System: Main Root grows straight down, anchors the plant, and stores nutrients
• Fibrous Root System: Many roots, provides stability and absorbs water
• Adventitious Root System: Unusual roots, develops from stems or leaves, supports, breathes, and stores food

Types of Microscopes

• Simple Microscope: Single lens magnification
• Compound Microscope: Multiple lenses system
• Electron Microscope: Uses electron beams for high-resolution images
• Fluorescence Microscope: Uses fluorescence or phosphorescence to study properties
• Digital Microscope: Displays image digitally, often connected to a computer

Cell Theory

• All known living things are made up of one or more cells
• All living cells arise from pre-existing cells by division
• The cell is the fundamental unit of structure and function in all living organisms
• The activity of an organism depends on the total activity of independent cells
• Energy flow (metabolism and biochemistry) occurs within cells
• Cells contain DNA which is found specifically in the chromosome and RNA
• All cells are basically the same in chemical composition in organisms of similar species

Organelles Function & Structure Plant vs. Animal Cell

• Plant cells are rigid and autotrophic, while animal cells are flexible and heterotrophic
• Plant cells have a cell wall, which provides structure and support, while animal cells do not
• Plant cells contain chloroplasts, which are responsible for photosynthesis, while animal cells do not
• Plant cells have a larger central vacuole, which stores nutrients and waste, while animal cells have smaller, more numerous vacuoles