ETC

Question 1

The ETC is in the-

Answer 1

Inner mitochondrial membrane

Question 2

The protein complexes and other molecules of the ETC exchange -

Answer 2

Energy rich electrons
-Electron exchange is like an electrical current
-Electron flow through the ETC energizes ATP synthase to make ATP

Question 3

The ETC generates the ________ across the inner mitochondrial membrane

Answer 3

Hydrogen ion concentration gradient

Question 4

Electron flow energizes each protein complex to transport ___ ions across the ____ into the inter-membrane space

Answer 4

H+
Inner mitochondrial membrane
-This increases H+ concentration in the inter-membrane space
-The H+ ion concentration gradient is an energy source

Question 5

The H+ concentration gradient across the inner mitochondrial membrane energizes the-

Answer 5

ATP synthase enzyme
-Each ATP synthase enzyme makes ~400 ATP molecules/second
-There are many ATP synthase enzymes in the inner membrane

Question 6

_____ & ______ supply energy rich electrons to the ETC

Answer 6

NADH & FADH2

Question 7

H+ ions diffuse “down the gradient” from high to low [] to activate-

Answer 7

ATP synthase enzymes to make ATP molecules

Question 8

ATP synthase consists of 2 parts-

Answer 8

1. The F0 part in the inner mitochondrial membrane is the channel portion through which H+ ions diffuse
2. The F1 part is the catalytic subunit whose active site adds PO4 to ADP to make ATP (the diffusion of H+ ions through the F0 part activates the F1 part)

Question 9

Summarize ATP production during cellular respiration

Answer 9

-The catabolism of 1 glucose molecule produces ~32-38 ATP depending on cell type
-Glycolysis produces 7/8 ATP per glucose molecule
-Pyruvate oxidation produces 5/6 ATP per glucose
-Krebs cycle produces 20/24 ATP per glucose

Question 10

In addition to glucose, food contains other calorie rich biological molecules that cells catabolize to make ATP

Answer 10

-Food contains lipids, nucleic acids, proteins, and other carbs
-Your cells convert these molecules into substrates that enter cellular respiration

Question 11

Aerobic species require ____ molecules to perform cellular respiration, synthesize ATP, and live

Answer 11

O2 molecules

Question 12

O2 removes electrons from the ETC to enable the-

Answer 12

-Electrons to continue flowing through the ETC
-H+ ion concentration gradient to continue forming
-Continues activation of ATP synthase to make ATP

Question 13

Cyanic (CN) is a lethal metabolic poison that inhibits the _____ enzyme complex in the ETC

Answer 13

Cytochrome C oxidase
Eliminates the:
-Flow of electrons through the ETC
-H+ ion [] gradient across the inner mitochondrial membrane
-Synthesis of ATP molecules by ATP synthase

Question 14

Dinitophenol (DTP) is a metabolic poison that reduces, but does not eliminate, ATP synthesis in the mitochondrion

Answer 14

-DNP reduces the magnitude of the H+ ion [] gradient
-DNP binds to the H+ ions & transports them across the inner membrane
-Fewer H+ ions are available to activate ATP synthase
-DNP “uncouples” ATP synthesis from electron flow in the ETC

Question 15

DNP has therapeutic potential due to its ability to change the biology of mitochondria

Answer 15

Low doses of DNP could treat metabolic syndrome, neurodegenerative disorders, and obesity