Download BioCore II lecture6

1. Sit with Lab Group
Find members of your group
2. Attendance with your phone
Launch your Top Hat app on your smart phone
or load the TopHat.com website, or text to the
course’s phone number.
Prepare for Pop Quiz at start of lecture
Pop Quiz!
2
If you were a prokaryotic cell, you would be lacking _____.
a. a plasma membrane composed of phospholipids and proteins
b. chromosomes that contain genetic information
c. ribosomes to synthesize proteins
d. mitochondria to generate ATP
Why is the smooth endoplasmic reticulum unable to
synthesize proteins?
a.
b.
c.
d.
It has no ribosomes.
There is no supply of free amino acids that it can easily access.
It stores calcium, which is known to inhibit protein synthesis.
It has no DNA to direct the synthesis of proteins.
What does a motor protein do in a cell?
a.
b.
c.
d.
causes microtubules to “treadmill”
converts ATP into mechanical energy in the form of movement
triggers receptor-mediated endocytosis
aids in the transport of newly synthesized proteins from the
endomembrane system
e. Some of the above
f. All of the above
Which of the following is NOT considered a benefit of
compartmentalization in eukaryotes?
a. Chemical reactions are more efficient because substrates are more
easily maintained at high concentrations within organelles.
b. Chemical reactions that are incompatible can be segregated in different
organelles.
c. DNA is transcribed and translated at significantly higher rates because
all of the machinery is inside a single, membrane-bound nucleus.
d. When the product of one reaction is the substrate for a second reaction,
the enzymes that work together can be clustered together on internal
membranes and result in greater speed and efficiency.
Molecular “zip codes” direct molecules to specific
destinations in the cell. How do you predict these
signals are read?
a. They bind to receptor proteins.
b. They enter transport vesicles.
c. They bind to motor proteins.
d. They are glycosylated by enzymes in the Golgi apparatus.
END
Pop Quiz!
8
ANY Questions about
Pop Quiz?
9
Glucose
Pancreas secretes
INSULIN
Glycogen
Insulin causes cells in the liver and skeletal
muscle to synthesize glycogen; fat storage
cells synthesize triglycerides.
Glucose
levels fall
HOMEOSTASIS
If glucose
levels too low
Pancreas secretes
GLUCAGON
(normal glucose
levels in blood)
Glucose
levels rise
Glucagon causes cells in liver and skeletal
muscle to catabolize glycogen; fat storage
cells catabolize fatty acids.
Glycogen
Glucose
Last time…Chalk Talk
“How to make the hormone insulin”
NOW: Must learn biosynthesis path for
-> nuclear, membrane, cytoplasmic
Review the drawing: what is the mutant path?
What happens at the end for insulin, a secreted protein?
Sorting, tagging, packaging, and distribution of lipids and proteins takes place in the Golgi apparatus, which are?
Send me photos of your art for bonus points
Which structure is not part of the
endomembrane system?
Which structure is not part of the endomembrane system?
A.
B.
C.
D.
E.
nuclear envelope
chloroplast
Golgi apparatus
plasma membrane
ER
What correctly characterizes
“bound” ribosomes?
If you inject lots of radioactively labeled S-35 leucine
(it’s an amino acid) into a pancreatic cell making
hormones.… what is the likely path the
radioactivity will take?