BIOLOGY 181 EXAM EVALUATION 2025/2026 QUESTIONS
AND ANSWERS GRADED A+
✔✔A ribosome binds to the mRNA and a short stretch of protein is synthesized that
contains a signal sequence. - ✔✔For a protein to enter the endoplasmic reticulum as
part of the endoplasmic reticulum's lumen or part of the endoplasmic reticulum's
membrane:
The messenger RNA goes directly to the ER.
A ribosome binds to the mRNA and a short stretch of protein is synthesized that
contains a signal sequence.
Ribosomes at the endoplasmic reticulum bind to the protein
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.
None of the above.
✔✔True - ✔✔Facilitated diffusion uses a channel protein to let components move down
their concentration gradient.
✔✔False - ✔✔The ER is contiguous with the Golgi apparatus.
✔✔Ligands that are used in cell communication. - ✔✔When a vesicle fuses with the
plasma membrane the contents of the lumen of the vesicle are:
Ligands that enter the nucleus.
Ligands that become the part of the plasma membrane.
Ligands that are used in cell communication.
Two of the above.
Part of the nuclear pore complex.
✔✔False - ✔✔Active transport uses ATP to move components in parallel with their
concentration gradient, that is: from a high concentration to a low concentration.
✔✔False - ✔✔It is a simple matter (i.e., thermodynamically favorable) for a vesicle to
form from the endoplasmic reticulum.
AND ANSWERS GRADED A+
✔✔A ribosome binds to the mRNA and a short stretch of protein is synthesized that
contains a signal sequence. - ✔✔For a protein to enter the endoplasmic reticulum as
part of the endoplasmic reticulum's lumen or part of the endoplasmic reticulum's
membrane:
The messenger RNA goes directly to the ER.
A ribosome binds to the mRNA and a short stretch of protein is synthesized that
contains a signal sequence.
Ribosomes at the endoplasmic reticulum bind to the protein
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.
None of the above.
✔✔True - ✔✔Facilitated diffusion uses a channel protein to let components move down
their concentration gradient.
✔✔False - ✔✔The ER is contiguous with the Golgi apparatus.
✔✔Ligands that are used in cell communication. - ✔✔When a vesicle fuses with the
plasma membrane the contents of the lumen of the vesicle are:
Ligands that enter the nucleus.
Ligands that become the part of the plasma membrane.
Ligands that are used in cell communication.
Two of the above.
Part of the nuclear pore complex.
✔✔False - ✔✔Active transport uses ATP to move components in parallel with their
concentration gradient, that is: from a high concentration to a low concentration.
✔✔False - ✔✔It is a simple matter (i.e., thermodynamically favorable) for a vesicle to
form from the endoplasmic reticulum.
