Importance of ATP Flashcards
ATP
A nucleotide and the major currency of the cell, used for all reactions in all cells. It’s inert, soluble, easily transported, and releases energy efficiently.
3 phosphate groups, ribose sugar, adenosine
What does ATPase do?
Hydrolyses the terminal bond between middle and furthest away from ribose phosphate which releases energy in useable amounts so little is wasted as heat.
How is ATP reformed?
Phosphorylation when a phosphate group is added to ADP by condensation (ADP + Pi > ATP)
Where does ATP synthesis take place?
Internal membranes of mitochondria and chloroplasts.
Describe the process of ATP synthesis.
Protons must pass through ATP synthetase, found in the stalked particles of inner membranes. This flow of protons generates an electrochemical gradient, a source of energy. This drives the phosporylation of ADP to form ATP. This is chemiosmosis.
Chemiosmosis
The flow of protons down an electrochemical gradient through ATP synthetase, providing energy to synthesis ATP by phosphorylation.
In mitochondria, where do protons flow?
From the intermembrane space into the matrix.
In chloroplasts, where do protons flow?
Across the thylakoid space into the stroma.
Name the structures in mitochondria.
Intermembrane space, matrix, crista, outer membrane, and stalked particles.
Name the structures in chloroplast.
Thylakoid space, stalked particles, outer membrane, thylakoid membrane, and stroma.
Where are protons pumped across a membrane by proton pumps in mitochondria and chloroplast?
Mitochondria - crista
Chloroplast - thylakoid membrane
Where do a high concentration of protons build up in mitochondria and chloroplast?
Mitochondria - intermembrane space
Chloroplast - thylakoid space
Where do protons flow down a concentration gradient to get energy for ATP synthesis in mitochondria and chloroplast?
Mitochondria - stalked particles
Chloroplast - stalked particles
Where do free electrons get taken by an electron acceptor in mitochondria and chloroplast?
Mitochondria - matrix
Chloroplast - stroma
Where is the ETC located in the mitochondria and chloroplast?
Mitochondria - inner membrane
Chloroplast - thylakoid membrane
What generates a proton gradient?
Proton pumps and electron carriers
Describe the process of chemiosmosis.
High energy electrons pass from electron carrier to electron carrier, providing energy to proton pumps
Protons pumped into intermembrane space
Proton gradient allows protons to pass back into matrix/stroma via ATP synthetase
Electrochemical gradient provides energy for phosphorylation of ADP to ATP
Describe the end of ETC.
A flow of protons pass through ATP synthetase, generating energy for ATP synthesis by oxidative phosphorylation and oxygen becomes the final electron acceptor.
