Page |1
ASU BIO 181 EXAM 1 NEWEST 2025/2026 NEWEST ACTUAL
EXAM WITH COMPLETE QUESTIONS AND VERIFIED
ANSWERS |ALREADY GRADED A+|
What is the difference between a single-pass transmembrane
protein and a 7-pass transmembrane protein? - ANSWER-
Because the inside of the phospholipid bilayer of the cell
membrane is hydrophobic, this one hydrophobic peak indicates
the glycophorin only cross the phospholipid bilayer once, and thus
a single pass protein. Multi pass proteins cross the plasma
membrane multiple times.
A single pass trans-membrane protein that is an alpha helix can
make a channel. - ANSWER-FALSE
Cholesterol is _____ to have in biological membranes. -
ANSWER-Good
Explain the evolutionary origin of the endoplasmic reticulum, Golgi
apparatus and vesicles. - ANSWER-The endoplasmic reticulum
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(ER) plays a key role in the modification of proteins and the
synthesis of lipids.
The Endoplasmic reticulum, Golgi, and vesicles all evolved from
the endomembrane system which is when the cells surface
became flexible many millions of years ago due to losing the cell
wall. This allowed for the exchanging of material with the
environment to happen rapidly, which then lead to the cell to
sustain a larger volume and have a more rapid metabolism.
The ER is contiguous with the nuclear envelope. - ANSWER-
TRUE
Facilitated diffusion uses a channel protein to let components
move down their concentration gradient. - ANSWER-TRUE
Explain how the vesicles are carried from the Golgi apparatus to
the plasma membrane. - ANSWER-The vesicles are carried from
the Golgi to the plasma membrane by the microtuble system
(which doesn't reach all the way to the plasma membrane) so
then it later goes to the actin filament system (which are
connected to plasma membrane)
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For a protein to enter the endoplasmic reticulum as part of the
endoplasmic reticulum's lumen or part of the endoplasmic
reticulum's membrane:
A. The messenger RNA goes directly to the ER.
B. A ribosome binds to the mRNA and a short stretch of protein is
synthesized that contains a signal sequence.
C. Ribosomes at the endoplasmic reticulum bind to the protein
D. Is a random event and one day the protein could go to the ER
and on another day the same protein could associate with a free
polyribosome.
E. None of the above. - ANSWER-B. A ribosome binds to the
mRNA and a short stretch of protein is synthesized that contains a
signal sequence.
Explain the evolutionary origin of mitochondria. - ANSWER-
Anaerobic eukaryote engulfed an aerobic alpha-proteobacterium
which then became an endosymbiont providing ATP from
respiration while receiving substrates and protection
ASU BIO 181 EXAM 1 NEWEST 2025/2026 NEWEST ACTUAL
EXAM WITH COMPLETE QUESTIONS AND VERIFIED
ANSWERS |ALREADY GRADED A+|
What is the difference between a single-pass transmembrane
protein and a 7-pass transmembrane protein? - ANSWER-
Because the inside of the phospholipid bilayer of the cell
membrane is hydrophobic, this one hydrophobic peak indicates
the glycophorin only cross the phospholipid bilayer once, and thus
a single pass protein. Multi pass proteins cross the plasma
membrane multiple times.
A single pass trans-membrane protein that is an alpha helix can
make a channel. - ANSWER-FALSE
Cholesterol is _____ to have in biological membranes. -
ANSWER-Good
Explain the evolutionary origin of the endoplasmic reticulum, Golgi
apparatus and vesicles. - ANSWER-The endoplasmic reticulum
, Page |2
(ER) plays a key role in the modification of proteins and the
synthesis of lipids.
The Endoplasmic reticulum, Golgi, and vesicles all evolved from
the endomembrane system which is when the cells surface
became flexible many millions of years ago due to losing the cell
wall. This allowed for the exchanging of material with the
environment to happen rapidly, which then lead to the cell to
sustain a larger volume and have a more rapid metabolism.
The ER is contiguous with the nuclear envelope. - ANSWER-
TRUE
Facilitated diffusion uses a channel protein to let components
move down their concentration gradient. - ANSWER-TRUE
Explain how the vesicles are carried from the Golgi apparatus to
the plasma membrane. - ANSWER-The vesicles are carried from
the Golgi to the plasma membrane by the microtuble system
(which doesn't reach all the way to the plasma membrane) so
then it later goes to the actin filament system (which are
connected to plasma membrane)
, Page |3
For a protein to enter the endoplasmic reticulum as part of the
endoplasmic reticulum's lumen or part of the endoplasmic
reticulum's membrane:
A. The messenger RNA goes directly to the ER.
B. A ribosome binds to the mRNA and a short stretch of protein is
synthesized that contains a signal sequence.
C. Ribosomes at the endoplasmic reticulum bind to the protein
D. Is a random event and one day the protein could go to the ER
and on another day the same protein could associate with a free
polyribosome.
E. None of the above. - ANSWER-B. A ribosome binds to the
mRNA and a short stretch of protein is synthesized that contains a
signal sequence.
Explain the evolutionary origin of mitochondria. - ANSWER-
Anaerobic eukaryote engulfed an aerobic alpha-proteobacterium
which then became an endosymbiont providing ATP from
respiration while receiving substrates and protection
