Molecular oxygen (O2), which is required for the production of ATP by mitochondria, must pass through at least three membranes to get to the enzymes where it is used
O2 is also produced in chloroplasts and must pass through at least four membranes to be released from the plant. How does O2 move across biological membranes?
A. There are numerous protein transporters
that allow O2 to travel across membranes.
B. O2 is nonpolar, and very small, so it can
diffuse across the membrane.
C. O2 undergoes a chemical reaction that
binds it to other substances that are
transported across the membranes.
D. O2 is hydrophilic and travels with water
across the membranes.
Answer Key: B
You might also like to view...
A key difference between classification methods and identification methods is that classification methods are designed to
a. examine an organism's staining characteristics b. determine the oxygen requirements of an organism c. determine evolutionary relationships of organisms d. determine if an organism is resistant to antibiotics e. determine an organism’s pathogenicity
Transmission-Based Precautions
A. is a course health workers must take. B. are guidelines from WHO for dealing with emerging diseases. C. are instructions on the care of all patients. D. are guidelines to use with patients infected with a highly transmissible or epidemiologically important pathogen.
The binding of a neurotransmitter to ligand-gated K+ channels will cause ____ in the postsynaptic membrane
a. depolarization only b. hyperpolarization c. repolarization only d. apolarization e. depolarization and repolarization
Food is classified as chyme in the ____
a. large intestine b. liver c. mouth d. small intestine e. stomach