Energy And ATP Flashcards
What does ATP stand for?
ATP stands for adenosine triphosphate.
What are the components of an ATP molecule?
An ATP molecule consists of the sugar ribose, the base adenine, and a chain of three phosphate groups.
How is ATP formed?
ATP is formed when a phosphate group binds to a molecule of ADP (adenosine diphosphate).
What type of reaction is phosphorylation?
Phosphorylation is a type of reaction where a phosphate group is added to another molecule.
What type of reaction is endothermic?
An endothermic reaction is a type of reaction that absorbs energy.
What enzyme catalyzes the synthesis of ATP?
ATP synthase catalyzes the synthesis of ATP.
What drives the synthesis of ATP?
The synthesis of ATP is driven by light in the light-dependent reactions of photosynthesis and by the oxidation of sugars, lipids, and proteins in cellular respiration.
What happens to the energy released during cellular respiration?
The energy released drives the phosphorylation of ADP and is stored in the chemical bonds of the ATP molecules produced.
What is ATP?
ATP is an immediate source of energy for biological processes.
What happens when ATP combines with water?
The bond binding the endmost phosphate group to the rest of the ATP is broken.
What is the reaction called when ATP combines with water?
The reaction is called hydrolysis.
What occurs during the hydrolysis of ATP?
Energy is consumed breaking the bond, but more energy is released as other bonds are formed.
What is the overall nature of the hydrolysis reaction of ATP?
The overall reaction is exothermic.
What catalyses the hydrolysis of ATP?
The enzyme ATP hydrolase.
What is released during the hydrolysis of ATP?
Energy.
How is ATP formed
A phosphate group (Pi) bonds to a molecule of ADP (adenosine diphosphate)
The reaction forming ATP is:
-a phophorylation: a type of reaction where a phosphate group is added to another molecule
-endothermic: absorbs energy
-catalysed by the enzyme ATP synthase
The energy driving the synthesis of ATP comes from:
-light in the light dependent reactions of photosynthesis
-sugars (also lipids and proteins) which are oxidised in the reactions of cellular respiration
In each case the energy released drives the phosphorylation of ADP and is stored in the chemical bonds of the ATP molecule
What is ATP
An immediate source of energy for biological processes
Is ATP soluble in water
Yes very
What happens when a molecule of ATP combines with a water molecule
The bond binding the end most phosphate group to the rest of the ATP is broken. The reaction is hydrolysis.
It’s also exothermic
What is the hydrolysis of ATP catalysed by
The enzyme ATP hydrolase
What is produced when ATP is hydrolysed
The energy produced drives processes:
-anabolic reactions which result in the synthesis of polymers from building block units eg. Monosaccharides—> polysaccharides
-active transport
-muscle contaction
Examples of active transport
-transferring glucose from blood to liver cells
-the exchange of sodium ions and potassium ions across the membrane of the axon of a nerve cell generating an action potential
A proportion of the energy from the hydrolysis of ATP is released as:
Heat energy
In birds and mammals some heat is used to maintain a stable body temp
ATP summary
- releases relatively small amount of energy (danger of thermal death of cells)
- releases energy in a single step reaction (energy is readily available)
- phosphorylates other compounds making them more reactive
- can be rapidly re-synthesised
-is not lost from cells
Short term and long term energy stores
Short term
-glucose
Long term
-glycogen
-starch
