Download 4.7-4.16

Cell Types
Prokaryotic and Eukaryotic (Plant and Animal)
Prokaryotic
Eukaryotic (Plant)
Eukaryotic (Animal)
The Endomembrane System
4.7-4.14
-The Endomembrane System starts with ER (rough and smooth)
-ER is continuous with nuclear envelope
-membranes form compartments (network within a cell)
-smooth ER makes lipids (phospholipids, fatty acids, and steroids)
-smooth ER of muscle cells store calcium which are used to stimulate contraction
-smooth ER of human liver cells:
1. contain enzymes which regulate sugar released by liver into bloodstream
2. break down drugs and other harmful chemicals
Within the membrane of ER:
1. protein is made by ribosome attached to ER
2. sugars are added to protein (make glycoprotein)
3. glycoprotein is packaged into a transport vesicle
4. vesicle buds of and heads to golgi apparatus
-the golgi receives vesicles from the ER and chemically modifies them
-some chemical modifications are used to mark and sort proteins for export out of the cell
-one function of the shipping portion of the golgi is to package a finished protein into a vesicle to move to the plasma
membrane so it can be excreted from the cell
-Rough ER makes protein and membrane molecules
-Some proteins are hydrolytic (digestive) and will eventually form a lysosome after modification in the golgi
-The membranes of a lysosome keep digestive enzymes from destroying other parts of the cell
-lysosomes can function to break down large food molecules
-they can also break down worn out organelles (their molecules can be used to make new organelles)
-Summary of Endomembrane System
-The golgi can make a vesicle for shipping protein, a lysosome, and a vacuole
-a plant vacuole can store water, vital chemicals, or waste products
-they can also store pigments that attract pollinating insects
a paramecium has vacuoles that work to expel excess water
Energy Converting Organelles
Chloroplast (4.15)
Mitochondria (4.16)
-chloroplasts convert light energy to chemical energy (glucose)
-the light energy is trapped in the granum (grana - plural)
-stroma is a fluid within the chloroplast we will cover in a later chapter
-mitochondria converts glucose into ATP (energy molecule used by a cell)
-the enzyme that does the conversion is located in the folded (folds called cristae) inner membrane
-more folds create more surface area which holds more enzymes
-most chemical reactions occur in matrix (fluid)
Homework:
• Packet Exercises 7 & 8
• Read 4.16-4.18