Cell Organelles Flashcards
Cells
smallest units of life ; over 250 ; cells are very diverse
What are the 3 basic parts of cells?
Plasma membrane
Cytoplasm
Nucleus
Plasma Membrane
flexible outer boundary
Cytoplasm
intracellular fluid containing organelles
Nucleus
DNA controlling control center
Extracellular Materials
Substances found outside your cell
Interstitial fluid
cells are submersed (bathed) in this fluid
Blood plasma
fluid of blood
Cerebrospinal Fluid
fluid surrounding nervous system organs
Cellular Secretions
saliva and mucus ; external elimination of substances produced by the cell
Extracellular matrix
substance that acts as glue to hold cells together
Cytoplasm
All cellular material that is located between the plasma membrane and the nucleus
Cytosol
gel-like solution made up of water and soluble molecules such as proteins, salts, sugars, etc.
Cytoplasmic Organelles
These are divided into membranous (eukaryotes) and non membranous (prokaryotes)
Mitochondria
Called the “power plant” of cells because they produce most of cell’s energy molecules (ATP) via aerobic (oxygen-requiring) cellular respiration
- fact: mitochondria has its own DNA , all of mitochondrial DNA comes from your mom
Double Membranes
Mitochondria is enclosed by double membranes;
Cristae
The inner membrane of mitochondria has many folds, called cristae
Cristae are embedded with membrane proteins that play a role in cellular respiration
Ribosomes
- nonmembranous (no membrane around them)
- sites of protein synthesis
Membrane Bound Ribosomes
attached to membrane of endoplasmic reticulum (ER); site of synthesis of proteins to be incorporated into membranes or lysosomes, or exported from cell
Free Floating Ribosomes
free floating; site of synthesis of soluble proteins that function in cytosol or other organelles
Endoplasmic Reticulum
- folds of membrane outside the nucleus
- take MRNA that comes out of nucleus and feed it to ribosomes to produce proteins
Rough ER
External surface appears rough because it is studded with attached ribosome
Site of synthesis of proteins that will be secreted from cell
Site of synthesis of many plasma membrane proteins and phospholipids
Final protein is enclosed in vesicle and sent to Golgi apparatus for further processing
Smooth ER
- Network of looped tubules continuous with rough ER
- Enzymes found inside function to:
- Lipid metabolism; cholesterol and steroid-based hormone synthesis; making lipids for lipoproteins
-Absorption, synthesis, and transport of fats
-Detoxification of certain chemicals (drugs, pesticides, etc.)
-Converting of glycogen to free glucose
-Storage and release of calcium
Sacroplasmic Reticulum
specialized smooth ER found in skeletal and cardiac muscle cells
Golgi Apparatus
- continuation of ER
-Modifies, concentrates, and packages proteins and lipids received from rough ER
Three Steps in Golgi Apparatus
- Transport vesicles from ER fuse with cis (inner) face of Golgi
-Proteins or lipids taken inside are further modified, tagged, sorted, and packaged
- Golgi is “traffic director,” controlling which of three pathways final products will take as new transport vesicles pinch off trans (outer) face