- Dense body of RNA and Protein
- Found in certain chromosomes
- Factory for Ribosomes
- Cell may contain more than one (especially if the cell is producing proteins)
Transports substances in and out of the cell
- Cilia: Tiny hair like parts that are on the Epithelial cells
- Move fluids/substances across cell surfaces
- Usually found in the respiratory tract and Fallopian tubes
- Flagella: Single mobile thread like projection (tail)
- Larger than Cilia
- Found in sperm cells (allows movement)
- Contain centrioles composed of microtubules
- Lie at right angles to each other in the cytoplasm near the Golgi Apparatus and Nucleus
- Aid in cell reproduction
- Organize spindle fibers during cell division
- 55% of the weight of the cell membrane
- Integral- most span the entire cell membrane
- Globular: more compact, serves as a channel for transport
- Fibrous: more tightly coiled, rod like, serve as receptors
- Peripheral - associated with the inner or outer surface fo the cell membrane
- May function as enzymes
Embedded in the interior to make the membrane less permeable to water soluble substances and to help stabilize the membrane.
2 Layers of Phospholipid Bilayer
Hydrophilic- (water-loving) "heads" contains phosphates, forms the "Surface" of the cell membrane
Hydrophobic- (water-fearing) "tails", made up of fatty acids, forms the "Interior" of the cell membrane
Cell (Plasma) Membrane
- Outer layer that contains the materials within the cell
- Selective permeable (allows some things through...ie calcium potassium, while rejecting others)
- Phospholipid Bilayer (Hydrophilic...water-loving...heads & Hydrophobic....water-fearing...tails).
- Membranous sacs that contain digestive enzymes
- "Garbage disposals" of the cell
- Vescicles but with a specific purpose of removing garbage
- Contains a small amount of DNA that provides info for making a few kinds of proteins and specialized RNA
- "Power house" of cells / releases energy from food to form ATP (Adenosine Triphosphate)
- Divide in half (fission) and grow back to former size if more are needed.
- Composed of protein and RNA
- "Protein Factories" protein is synthesized here
- More abundant in the Rough ER (Endoplasmic Reticulum), but also some are free floating in the cytoplasm.
- Receives molecules from the ER
- Has membranous sacs called Cisternae
- Refines packages and delivers the proteins synthesized by the ribosomes
- Includes processing and packaging of lysosome enzymes
Endoplasmic Reticulum (ER)
- Communicates with the cell membrane, nuclear envelope and certain organelles
- Provides a tubular transport system for molecules throughout the cell
- 2 types: Smooth ER - no ribosomes, has enzymes for both lipid and carb. synthesis. Rough ER - contains ribosomes, site of protein synthesis.
- Material between cell membrane and Nucleus
- Contains cytosol, 90% water, contains amino acids, simple sugars and other substances to manufacture larger molecules.
- Contains thousands of enzymes
- Functions: Site where most cellular activities occur (Metabolism). Site where food molecules are received, processed and used.