Pre AP Biology -CELLS 3.1 Cell Membrane Structure- MCQ Exam Style Questions -New Syllabus

Pre AP Biology -CELLS 3.1 Cell Membrane Structure- MCQ Exam Style Questions – New Syllabus 2025-2026

Pre AP Biology -CELLS 3.1 Cell Membrane Structure- MCQ Exam Style Questions – Pre AP Biology – per latest Pre AP Biology Syllabus.

Pre AP Biology – MCQ Exam Style Questions- All Topics

Question

You recently travelled to a tropical island and, upon your return, you start feeling fatigued, nauseated, and have a loss of appetite. You feel some abdominal pain on your right side beneath your lower ribs and you notice your stool is clay-coloured. Which of the following is the most likely reason for your condition?

a. You contracted hepatitis B, caused by a virus from $Papovaviridae$ viral family.

b. You contracted hepatitis B, caused by a virus from $Picornaviridae$ viral family.

c. You contracted hepatitis A, caused by a virus from $Picornaviridae$ viral family.

d. You contracted hepatitis A, caused by a virus from $Papovaviridae$ viral family.

▶️ Answer/Explanation

Detailed solution

The symptoms of fatigue, nausea, and right-sided abdominal pain suggest acute viral hepatitis.
Clay-coloured stools indicate a lack of bile pigment, typically caused by liver inflammation or bile duct obstruction.
Hepatitis A is commonly associated with travel to regions with poor sanitation via the fecal-oral route.
The Hepatitis A virus ($HAV$) is a member of the $Picornaviridae$ family.
Hepatitis B belongs to the $Hepadnaviridae$ family, not $Papovaviridae$ or $Picornaviridae$.
Therefore, the most likely diagnosis is Hepatitis A caused by a $Picornaviridae$ virus.
The correct option is c.

Question

The integral membrane protein rhodopsin, which is used in light perception, is a protein that spans the membrane seven times. What does this tell you about rhodopsin’s structure?

a. It contains seven hydrophobic amino acids.
b. It is composed only of hydrophobic amino acids.
c. It contains both hydrophobic and hydrophilic domains.
d. It contains one long stretch of hydrophobic amino acids.

▶️ Answer/Explanation

Detailed solution

The correct option is c.
Rhodopsin is an integral membrane protein that must interact with both the oily interior and watery exterior of the cell.
To span the membrane $7$ times, it requires hydrophobic domains (alpha-helices) to sit within the lipid bilayer.
It also requires hydrophilic domains for the loops and ends that face the aqueous cytoplasm and extracellular space.
Option a is incorrect because each of the $7$ spans requires many amino acids, not just one.
Option b is incorrect because a purely hydrophobic protein would be unstable in aqueous environments.
Option d is incorrect as the protein weaves in and out, creating multiple distinct hydrophobic segments.

Question

Suppose that you want to find out if the arrangement of membrane lipids and proteins in the membrane is symmetric. Which of these methods would you use?

a. light microscopy
b. scanning microscopy
c. the freeze-fracture technique
d. the Frye–Edidin experiment

▶️ Answer/Explanation

Detailed solution

The correct answer is c. the freeze-fracture technique.
This method involves freezing a specimen and hitting it with a sharp blade.
The fracture line often travels through the hydrophobic interior of the lipid bilayer.
This splits the membrane into two separate leaves: the P-face and the E-face.

Researchers can then observe the distribution of proteins on each interior face.
This directly reveals the asymmetric arrangement of proteins within the bilayer.
In contrast, the Frye–Edidin experiment measures lateral mobility, not structural symmetry.

Pre AP Biology -CELLS 3.1 Cell Membrane Structure- MCQ Exam Style Questions -New Syllabus