ATP, Water and Inorganic Ions Flashcards
Why is ATP useful?
- Release energy in small amounts.
- Broken down in single reaction (releases energy rapidly).
- Add phosphate to other molecules (makes them more reactive).
- Easily resynthesised.
What does ATP stand for?
Adenosine Triphosphate.
What doe ADP stand for?
Adenosine Diphosphate.
What does ATP synthase do?
Form ATP from ADP + Pi.
What does ATP hydrolase do?
Breaks down ATP into ADP + Pi.
What is ATP made up of?
- Ribose.
- Adenine.
- Three phosphate groups.
Why is hydrolysis of ATP useful?
can be coupled with energy requiring reactions within cells.
What is released in the hydrolysis of ATP and how it is used?
Inorganic phosphate is released which can be used to phosphorylate other compounds, making them more reactive.
What is the structure of water?
Its a polar molecule made up of two hydrogen atoms (slightly positive) and one oxygen atom (slightly negative). These atoms are held together by covalent bonds.
How do water molecules bond to each other?
The polarity of water allows weak attractions called hydrogen bonds to form between water molecules; the negative oxygen atom of one water molecule attracts the positive hydrogen atom of another water molecule.
What is a solvent?
A liquid that other substances can dissolve in.
Why is water know as the universal solvent?
Due to its polarity, with many chemical reactions taking place in aqueous solutions. Charged or polar molecules readily dissolve in water while uncharged molecules do not.
How does sodium chloride dissolve in water?
Sodium chloride (NaCl) produces positive sodium ions and negative chlorine ions when it is dissolved in water. The positive oxygen molecule in water attracts the negative chlorine ions, while the negative hydrogen molecules in water attract the positive sodium ions.
Why is water known as a metabolite?
Water is important in many reactions (e.g. condensation & hydrolysis).
What is cohesion?
Water molecules stick to each other because of their hydrogen bonds.
Why is cohesion an important characteristic of water?
- Makes it possible to pull water uphill (e.g. xylem)
- Responsible for surface tension when water meets air (pond skaters).
What is meant by water having a high latent heat of vaporisation?
It takes a lot of energy to break the hydrogen bonds between the molecules. This means evaporation is an effective form of cooling.
What is meant by water having a high specific heat capacity?
It takes a lot of energy to heat up or cool down water because of the hydrogen bonds between its molecules. This means that aquatic environments remain a relatively stable temperature.
What characteristic of water allows our internal body temperatures to change slowly?
High specific heat capacity.
What is an ion?
An atom that has left or gained electrons.
What is meant by the term inorganic?
A compound that doesn’t contain carbon.
Where do inorganic ions occur?
In the cytoplasm and body fluids.
What is pH a measure of?
H+ ions in a solution.
Why are sodium ions important?
They help to move other molecules across membranes (Co-transport).
Why are iron ions important?
Important in haemoglobin as they carry oxygen.
Where are phosphate ions important?
In ATP and in RNA/DNA (condensation reactions between phosphate groups to form polynucleotides).
