Overview
The lecture covers cell theory, cell structure, and function, emphasizing differences and similarities in plant and animal cells, levels of biological organization, and the roles of organelles.
Cell Theory
- All living things are composed of one or more cells.
- Cells are the basic unit of structure and function in living things.
- All cells arise from pre-existing cells.
Levels of Organization
- Living things are organized in levels: cell, tissue, organ, organ system, organism.
- Each level builds upon the previous one to form complex living systems.
Plant vs. Animal Cells
- Plant and animal cells share many organelles but differ in some structures and functions.
- Plant cells have a cell wall and chloroplasts; animal cells do not.
- Both types contain a cell membrane, cytoplasm, nucleus, mitochondria, and vacuoles.
Cell Organelles and Functions
- Cell membrane controls what enters and exits the cell.
- Cell wall provides structure and support (plant cells only).
- Nucleus directs cell activities and contains DNA.
- Cytoplasm is the gel-like fluid that holds organelles.
- Mitochondria produce energy through cellular respiration.
- Chloroplasts perform photosynthesis (plants only).
- Vacuoles store water and nutrients.
- Lysosomes break down waste (mainly animal cells).
Energy Needs and Processes
- Plants get energy via photosynthesis in chloroplasts using sunlight, water, and carbon dioxide.
- Animals obtain energy by consuming food and using mitochondria for cellular respiration.
- Both plants and animals need energy to survive and carry out life functions.
Comparing Cells to Organisms
- Cells remove waste, obtain energy, and perform functions similar to whole organisms.
- Organelle structure relates directly to its specific function for cell survival.
Key Terms & Definitions
- Cell — Basic unit of life in all organisms.
- Organelle — Specialized structure within a cell that performs a specific function.
- Nucleus — Organelle containing DNA and controlling activities.
- Cell Membrane — Barrier that regulates movement in and out of the cell.
- Cell Wall — Rigid outer layer in plant cells for support.
- Mitochondria — Organelle responsible for energy production.
- Chloroplast — Organelle for photosynthesis in plant cells.
- Vacuole — Organelle for storage of water and nutrients.
- Tissue — Group of similar cells working together.
- Organ — Group of tissues performing a specific function.
- Organ System — Group of organs working together.
Action Items / Next Steps
- Complete a cell model project using household items, labeling each organelle.
- Review vocabulary and organelle functions for upcoming quiz and test.
- Create a Venn diagram comparing plant and animal cells.
- Study levels of biological organization and cell theory statements.