Cell Structure and Function PDF

Cell Structure and Function Eukaryotic Cell Structure & Function Cell Membrane Purpose: Serves as a barrier This separates life from non-life Determines what comes in and goes out of the cell Provides some structure Aids in shaping the cell...

Cell Structure and Function Eukaryotic Cell Structure & Function Cell Membrane Purpose: Serves as a barrier This separates life from non-life Determines what comes in and goes out of the cell Provides some structure Aids in shaping the cell somewhat Composition: Phospholipid bilayer Hydrophilic heads and hydrophobic tails Sterols Lipids that provide extra support Proteins Provide support Cytoplasm Purpose: Provides aqueous solution for metabolic rxns Provides support for internal structures Composition Primarily water Proteins, carbohydrates, lipids, salts, acids, bases, etc. Cytoskeleton Purpose: Support/structure Transport Structure Protein fibers Microtubules Tubulin Hollow tubes Microfilaments Actin Two strands Intermediate filaments Various Coiled Nucleus Purpose: Holds the DNA of the organism Provide a place for early stages of protein creation Structure: Large, spherical organelle Double membrane Nuclear envelope DNA in the center in nucleolus Arranged in chromosomes Associated proteins make chromatin Nuclear pores allow for information transmission Endomembrane System Purpose: Create macromolecules Transport macromolecules Structure Nuclear membrane Transmits information Endoplasmic reticulum Rough: creates proteins Smooth: creates CHOs and lipids Golgi apparatus Packages and finalizes macromolecules for transport Vesicles and vacuoles Transport and store substances Cell membrane Brings in some substances, puts others out Ribosomes Purpose: Protein synthesis Structure: Protein + RNA Large subunit + small subunit Mitochondria & Chloroplasts Energy-generating organelles Animals: Mitochondria Plants: Mitochondria & chloroplasts Create ATP Energy “currency” of the cell Originated through endosymbiosis Once were independent bacteria that were engulfed and became part of a larger cell Appendages Locomotor structures Flagella Long, whip-like structures Move like snakes Cilia Shorter structures that Move like oars Extracellular Components Cell walls Found in plants, fungi, algae Rigid structure Provides shape/support/protec tion Help maintain correct level of water Extra cellular matrix Found in animals Provides some shape/support/protec Cell Junctions Cells are often connected with junctions Plant cells Plasmodesmata Animal cells Tight junctions Desmosomes Gap junctions