Transcript LB145-lecture5

Announcements
• Textbook: Notice “Key Concepts”
Test the endosymbiosis hypothesis…
1. What evidence could you look for?
2. Design an experiment: PCR, scope, antibiotic?
Evidence for Endosymbiosis
Mitochondria/Chloroplasts
Bacteria
Morphology/Behavior: They swim around in your
cells, divide, look like cyanobacteria etc
Anatomy: Have 2 membranes, inner like bacteria
& outer like plasma membrane.
Molecular: Their own genes & ribosomes, that
function- sequences of genes, ribosomes, same
as bacteria, antibiotic, circular no histones
Pathogens: Undigested prey or parasites via endo
3
Which structure is not part of the endomembrane system?
A. nuclear envelope
B. chloroplast
C. Golgi apparatus
D. plasma membrane
E. ER
Which statement correctly characterizes
“bound” ribosomes?
A. Bound ribosomes are enclosed in a membrane.
B. Bound and free ribosomes are structurally different.
C. Bound ribosomes generally synthesize membrane
proteins and secretory proteins.
D. The most common location for bound ribosomes is
the cytoplasmic surface of the plasma membrane.
A. All of the above.
Radioactively labeled amino acids in newly synthesized
proteins enables a researcher to track them. In this case,
we are tracking an enzyme secreted by pancreatic
cells. What is its most likely pathway?
A. ER→Golgi→nucleus
B. Golgi→ER→lysosome
C. nucleus→ER→Golgi
D. ER→Golgi→vesicles that fuse with plasma mem.
E. ER→lysosomes→vesicles that fuse with plasma
membrane
Chalk Talk
• How to make a CFTR channel