BIO 1107: Exam #2 2026 EXAM
QUESTIONS AND ANSWERS |
LATEST UPDATE
what is the structure of a phospholipid - ANSWER ✔✔glycerol
backbone attached to a phosphate group and two fatty acids
phosphate head and fatty acid tail
what does the shape of structures formed by phospholipids depend on -
ANSWER ✔✔the bulkiness of the head group relative to tails
what type of force is present between fatty acid tails in the lipid bilayer -
ANSWER ✔✔Van der Waals forces
, what two features of the lipids that make up the membrane affect its
fluidity - ANSWER ✔✔the length and the number of C-C double
bonds in the fatty acid tails
longer tails, less fluid the membrane
fewer C-C double bonds, less fluid the membrane
how does cholesterol impact membrane fluidity - ANSWER ✔✔- at
high temperatures, it decreases membrane fluidity (ring structure
interacts with tails)
- at low temperatures, cholesterol increases membrane fluidity (prevents
phospholipids from packing tightly with other phospholipids)
helps maintain a consistent temperature
integral membrane proteins - ANSWER ✔✔permanently associated
with cell membranes and cannot be separated from the membrane
without destroying the membrane itself
peripheral membrane proteins - ANSWER ✔✔temporarily associated
with the lipid bilayer or with integral membrane proteins through weak
non-covalent interactions
what types of molecules pass freely through the membrane -
ANSWER ✔✔small, nonpolar molecules
QUESTIONS AND ANSWERS |
LATEST UPDATE
what is the structure of a phospholipid - ANSWER ✔✔glycerol
backbone attached to a phosphate group and two fatty acids
phosphate head and fatty acid tail
what does the shape of structures formed by phospholipids depend on -
ANSWER ✔✔the bulkiness of the head group relative to tails
what type of force is present between fatty acid tails in the lipid bilayer -
ANSWER ✔✔Van der Waals forces
, what two features of the lipids that make up the membrane affect its
fluidity - ANSWER ✔✔the length and the number of C-C double
bonds in the fatty acid tails
longer tails, less fluid the membrane
fewer C-C double bonds, less fluid the membrane
how does cholesterol impact membrane fluidity - ANSWER ✔✔- at
high temperatures, it decreases membrane fluidity (ring structure
interacts with tails)
- at low temperatures, cholesterol increases membrane fluidity (prevents
phospholipids from packing tightly with other phospholipids)
helps maintain a consistent temperature
integral membrane proteins - ANSWER ✔✔permanently associated
with cell membranes and cannot be separated from the membrane
without destroying the membrane itself
peripheral membrane proteins - ANSWER ✔✔temporarily associated
with the lipid bilayer or with integral membrane proteins through weak
non-covalent interactions
what types of molecules pass freely through the membrane -
ANSWER ✔✔small, nonpolar molecules
