Week 3
Major concept goals
-The amphipathic nature and shape of lipids leads to the formation of lipid bilayers in H20
-The hydrophobic core of the bilayer can act as a barrier to the movement of polar and charged molecules
-Detergents are amphipathic and lead to an increase in the hydrophobicity of the environment
-Polarity and hydrophobicity determine both membrane and protein structure
-Membranes function as barriers and sites of reactions
-Most proteins that are added to mitochondria come from the cytosol
-Light microscopy cannot resolve if a protein is inside of or outside of a mitochindrion
-How a biochemical assay with purified mitochondria can be used to study the addition of proteins to this organelle
-Distinguishing a result from a conclusion
Overview of content
I. What organelles are made of
A. Membrane structure and function
1. What promotes the assembly of membranes by lipids
2. How and why do detergents disrupt membranes
3. Membranes as barriers and sites of activity
II. Making mitochondria
A. Do organelles like mitochondria need to be made? Why?
B. Models for where mitochondria come from/how they are made
1. New car model
2. Antique car model
C. Designing an experiment to distinguish between the two models for how mitochondria can be made
D. Mitochondria are likely made by the growth and division of pre-existing mitochondria
E. What needs to be added to mitochondria for them to be made?
III. Adding proteins to mitochondria
A. Where do they come from?
B. Limits of using microscopy to study the addition of proteins to mitochondria
C. Using a biochemical assay to study the addition of proteins to mitochondria
1. Purifying mitochondria
2. The assay using S35 labeled CoxIV
D. The assay with non-energized mitochondria
1. The result
2. The conclusion
E. The assay with energized mitochondria
1. The result
2. The conclusion
F. Data are facts and conclusions are what people think of the data (and are typically what are presented in a textbook)
G. The imported CoxIV is smaller, why?
H. CoxIV has an amphipathic alpha helix at its N-terminus, models for function?