Cells and Organelles Famous Men Leeuwenhoek first to

Cells and Organelles

Famous Men Leeuwenhoek: first to see living microorganisms Used Robert Used a simple microscope Hooke: named the cell a compound microscope to look at cork Reminded him of rooms in a monastery Called them cells

Cell Structure and Function Cells vary in size. Longest Smallest Cells cell- nerve cells (up to 2 meters long) cell- bacteria largest cell- egg vary in shape. Shape relates to function Blood cells are smooth, round, and flow easily through the blood vessels

Cell Theory T. Schwann: all animals are made of cells M. Schleiden: All plants are made of cells Virchow: All cells come from pre-existing cells Cell Theory All living things are made of cells 1. 1. multicellular- 2+ cells Cell is the basic unit of life 2. 1. 3. Unicellular- 1 cell The beginning unit is always a cell All cells come from other cells

Cell Types cell organelles-organs in a cell most important organelle= nucleus (controls all cell functions) Nucleus: Cell : : Brain: Body (a nucleus is to the cell what the brain is to the body) 2 Cell Types: Prokaryote no nucleus no membrane bound organelles simple contains: cell wall, cell membrane and ribosomes Bacteria ONLY Eukaryote nucleus membrane bound organelles complex Contains: nucleus and organelles Plants/Animals/Fungus

Nucleus- control center (contains chromatin) Chromatin- Tangles of DNA Nucleolus- located in the center of the nucleus, produces Ribosomes **only eukaryotes have a nucleus

Cell Wall Rigid Structure- does not move like the cell membrane Surrounds Cell membrane Provides Support Ex: Plants, fungi, some protists and bacteria

Ribosomes and Cytoplasm Ribosomes: Found on the Endoplasmic Reticulum or in the cytoplasm Site of Protein Synthesis All cells Cytoplasm: jelly-like substance between the nucleus and cell membrane Surrounds the organelles inside the cell A place for Chemical Reactions and Transport All cells

Endoplasmic Reticulum (ER) Folded Membrane (increased surface area) Assembly and transport of proteins and lipids Rough ER has attached ribosomes Eukaryotes only (plant and animals)

Mitochondrion Produces Energy (ATP) for the cell Inner folded membrane increases surface area, the greater the surface area the more area for production of ATP Eukaryotes only (plant and animal cells)

Golgi Body and Vacuole Golgi Body: Packaging and Shipping of Proteins and Lipids Packaged into Vesicles eukaryotes Vacuole Storage of Food, water, and waste Larger in plant cells- usually contains water

Chloroplast Photosynthesis happens here Contains chlorophylls that absorbs sunlight (green pigment) Plant cells only Light energy +CO 2+ H 2 O glucose+O 2

Microtubules, Microfilaments, and Lysosomes Microtubules and Microfilaments Protein fibers involved in cell movement and shape of the cell Moves organelles throughout the cell Lysosomes Used to digest food Used to break down the cell when it dies Animal cells only

Plasma Membrane Plasma membrane (Cell Membrane) Surrounds cell Maintains homeostasis Homeostasis-constant selectively Controls ALL internal environment permeable what enters and leaves the cell CELLS

Plasma Membrane Plasma Membrane- flexible outer boundary of a cell (like skin) Job- to maintain homeostasis (internal balance) Plasma Membrane is Selectively Permeable- chooses what passes through Selectively- choosy about what comes in and what goes out Permeable- allows to pass Fluid Mosaic Model- moves like a fluid with embedded proteins

Plasma Three 1. (Cell) Membrane is to cell as skin is to body molecules in the membrane: Phospholipid is the main molecule, a lipid that has a: Phosphate Group + Glycerol Backbone (Hydrophilic Head) 2 fatty acid chains- Tail (Hydrophobic) 1. 2. Saturated fatty acids make the membrane more rigid Unsaturated fatty acids makes the membrane more fluid-like

2. Membrane Protein Transport Proteins- help larger molecules get across the cell membrane Enzymes- help speed up the reaction Chemical Markers- help cells to identify each other Cell Signaling- messages from outside of the cell are communicated to the inside 3. Cholesterol Found in animal cells Lipid gives stability to the membrane

3 Differences between Plant and Animal Cells Plant cells have cell walls Plant cells have chloroplasts Plant cells have larger vacuoles