Other Membranous Organelles
Perxisome: membrane bound organelles that contain specialized teams of enzymes for specific metabolic pathways; all contain peroxide-- producing oxidases
-Breakdown of purines-- the G&A--nitrogen base!
-Produce hydrogen preoxide and break down hydrogen peroxide in plants
-In the liver, peroxisomes enzymatically transfer H from poisons to oxygen
*Mitochondria and chloroplasts are the main energy transformers of cells*
Mitochondria: organelles, which are the sites of cellular respiration, a catabolic oxygen-requiring process that uses energy extracted from organic macromolecules to produce ATP.
Two membranes that have their own unique combination of proteins embedded in phospholipids bilayer:
Outer membrane: highly permeable to solutes, but it blocks passage of proteins and other macromolecules
Inner membrane: contains embedded enzymes that are involved in cellular respiration.
The membrane's many infoldings or cristae increase the surface area available for these reactions to occur
Remember... DOUBLE MEMBRANE!
The inner and outer membranes divide the mitochondrion into two internal compartments:
Intermembrane space: narrow region between the inner and outer mitochondrial membranes
Mitochondrial Matrix:compartment enclosed by the inner mitochondrial membranes; contains enzymes
Plastids: a group of plants and algal membrane bound organelles that include amyloplasts, chromoplasts, and chloroplasts.
Amyloplasts: colorless plastids that store starch; found in roots and tubers
Chromoplasts: plastids containing pigments other than chlorophyll; responsible of the color of fruits, flowers and autumn leaves
Chloroplasts: chlorophyll- containing plastids, which are the sites of photosynthesis
Chloroplasts are divided into 3 functional compartments by a system of membranes
Intermembrane space: separates the double membrane
Tylakoid space: segregates the interior of the chloroplast into two compartments:
Thylakoid space: space inside the thylakoid
Stroma: viscous fluid outside the thylakoids
Thylakoid: Flattened membranous sacs inside the chloroplast
Here are a couple multiple choice questions to prepare for the quiz tomorrow!
Which structure is not apart of the endomembrane system?
a) nuclear envelope
c) Golgi apparatus
d) plasma membrane
Which structure is common to plants and animals cells?
b) wall made of cellulose
c) central vacuole
Which of the following is present in prokaryotic cells?
c) nuclear envelope
ANSWERS: b, d, b