3.1 Importance of ATP Flashcards
How is ATP ideally suited to its role?
- Is inert
- Can pass out of mitochondria into the cytoplasm
- Releases energy efficiently
- Releases energy in useable quantities, so little is wasted as heat
- Is easily hydrolysed to release energy
- Is readily reformed by phosphorylation
What is chemiosmosis?
The flow of protons down an electrochemical gradient, through ATP synthetase, coupled with the synthesis of ATP from ADP and a phosphate ion.
In the synthesis of ATP, what happens to electrons from hydrogen atoms?
Electrons from hydrogen atoms are transferred from a donor molecule to a recipient. Then a sequence of reactions transfers the electrons from one molecule to the next along a chain. Each transfer is a redox reaction, in which one molecule is oxidised, i.e. loses electrons, and in the next sequence is reduced, i.e. gains electrons. Oxidation reactions make energy available, and this energy is eventually used to synthesise ATP.
During the synthesis of ATP, what does the energy from oxidation do?
the energy released by oxidation pumps the protons from the hydrogen atoms across a membrane so that they are more concentrated on one side of the membrane than the other. The difference in the concentration of protons and the charge on either side of the membrane constitutes an electrochemical gradient, in a process called chemiosmosis, through the enzyme ATP synthetase. the energy they release as they do is converted into chemical energy in ATP.
What does phosphorylation mean?
3rd
phosphate group is reattached with a
high-energy bond, converting ADP back
into ATP.
Draw a basic structure of a mitochondria on your whiteboard and label it:
Anything you missed add to your drawing
Draw the basic structure of a chloroplast and label it:
Redo it if wrong
What does ATP synthetase do and how? What is this process called?
ADP is converted to ATP by the enzyme ATP synthetase
- ATP synthetase spans a membrane.
- The potential energy required to drive the enzyme to phosphorylate ADP comes from the flow of protons down an electrochemical gradient from one side of the membrane to the other by facilitated diffusion.
- This is chemiosmosis
What does the electron transport chain consist of and where is it located?
It is a series of protein carriers located on the inner membranes of mitochondria and chloroplasts.
Why is it we call the formation of ATP in respiration oxidative phosphorylation?
As the energy for the proton pump and the electron transport chain comes from oxidation reactions, and the addition of a phosphate group on to ADP is called phosphorylation, therefor oxidative phosphorylation is very fitting.
why is it the production of ATP in photosynthesis is called photophosphorylation?
As the energy for phosphorylation to occur comes from photons from light energy.
