MSCI 660 INTRACELLULAR MEMBRANE
TRAFFIC AND CELLULAR SORTING 2026
PROTEIN SORTING PATHWAYS REVIEW
QUESTIONS ANSWERS VERIFIED GUIDE
◉ What is oxidative phosphorylation?
Answer: A process in bacteria and mitochondria in which ATP
formation is driven by the transfer of electrons from food molecules
to molecular oxygen, with the intermediate generation of a proton
gradient across a membrane.
◉ What is the electrochemical gradient?
Answer: The result of a combined pH gradient and membrane
potential.
◉ What is cytochrome?
Answer: A colored, heme-containing protein that transfers electrons
during cellular respiration.
◉ What is an iron-sulfur cluster?
Answer: An electron-transporting group consisting of either two or
four iron atoms bound to an equal number of sulfur atoms.
,◉ What is ATP synthase?
Answer: An enzyme in the inner membrane of a mitochondrion that
catalyzes the formation of ATP from ADP and inorganic phosphate.
◉ What are light-driven reactions?
Answer: Reactions in photosynthesis in which electrons move along
the electron-transport chain in the thylakoid membrane.
◉ What is the antenna complex?
Answer: Part of a photosystem that captures light energy and
channels it into the photochemical reaction center.
◉ What is carbon fixation?
Answer: The process by which green plants incorporate carbon
atoms from atmospheric carbon dioxide into sugars.
◉ What is the photochemical reaction center?
Answer: The part of a photosystem that converts light energy into
chemical energy.
◉ What is a chloroplast?
Answer: An organelle in green algae and plants that contains
chlorophyll and carries out photosynthesis.
, ◉ What is chlorophyll?
Answer: A light-absorbing green pigment that plays a central role in
photosynthesis.
◉ What is the stroma?
Answer: The large space that surrounds the inner chloroplast
membrane.
◉ What is maternal inheritance?
Answer: A pattern of mitochondrial inheritance in higher animals
that arises because the egg cells always contribute much more
cytoplasm to the zygote than does the sperm.
◉ True or False: The most important contribution of the citric acid
cycle to energy metabolism is the extraction of high-energy
electrons during the oxidation of acetyl CoA to CO2.
Answer: True. The citric acid cycle extracts high-energy electrons,
which are crucial for ATP production.
◉ True or False: Each respiratory enzyme complex in the electron-
transport chain has a greater affinity for electrons than its
predecessors.
TRAFFIC AND CELLULAR SORTING 2026
PROTEIN SORTING PATHWAYS REVIEW
QUESTIONS ANSWERS VERIFIED GUIDE
◉ What is oxidative phosphorylation?
Answer: A process in bacteria and mitochondria in which ATP
formation is driven by the transfer of electrons from food molecules
to molecular oxygen, with the intermediate generation of a proton
gradient across a membrane.
◉ What is the electrochemical gradient?
Answer: The result of a combined pH gradient and membrane
potential.
◉ What is cytochrome?
Answer: A colored, heme-containing protein that transfers electrons
during cellular respiration.
◉ What is an iron-sulfur cluster?
Answer: An electron-transporting group consisting of either two or
four iron atoms bound to an equal number of sulfur atoms.
,◉ What is ATP synthase?
Answer: An enzyme in the inner membrane of a mitochondrion that
catalyzes the formation of ATP from ADP and inorganic phosphate.
◉ What are light-driven reactions?
Answer: Reactions in photosynthesis in which electrons move along
the electron-transport chain in the thylakoid membrane.
◉ What is the antenna complex?
Answer: Part of a photosystem that captures light energy and
channels it into the photochemical reaction center.
◉ What is carbon fixation?
Answer: The process by which green plants incorporate carbon
atoms from atmospheric carbon dioxide into sugars.
◉ What is the photochemical reaction center?
Answer: The part of a photosystem that converts light energy into
chemical energy.
◉ What is a chloroplast?
Answer: An organelle in green algae and plants that contains
chlorophyll and carries out photosynthesis.
, ◉ What is chlorophyll?
Answer: A light-absorbing green pigment that plays a central role in
photosynthesis.
◉ What is the stroma?
Answer: The large space that surrounds the inner chloroplast
membrane.
◉ What is maternal inheritance?
Answer: A pattern of mitochondrial inheritance in higher animals
that arises because the egg cells always contribute much more
cytoplasm to the zygote than does the sperm.
◉ True or False: The most important contribution of the citric acid
cycle to energy metabolism is the extraction of high-energy
electrons during the oxidation of acetyl CoA to CO2.
Answer: True. The citric acid cycle extracts high-energy electrons,
which are crucial for ATP production.
◉ True or False: Each respiratory enzyme complex in the electron-
transport chain has a greater affinity for electrons than its
predecessors.
