IT - Metals I Flashcards
How many essential elements are there?
25
How many elements are required in significant amounts (macronutrients)?
9
- S,P,Cl
- Si
- Na, K, Mg, Ca, Fe
What are the 4 metals present in all biological systems? Order them in occurence in humans
- Ca
- K
- Na
- Mg
What are 3 reasons for an element to be of use to an organism?
- It must be available in the local environment
- It must be abundant
- It must be accessible / extractable to the biological organism
Why are s-group metals used? (3)
- Outer electrons are easily lost
- Na+ and K+ found in cell communication
- Ionic bonds predominate as they are poor complexers
What are the properties of hard metals? (4)
- Small
- High charge
- Strong Lewis acids
- Bind hard ligands
What are the properties of soft metals? (4)
- Large
- Low charge
- Weak Lewis acids
- Bind soft ligands
What are the 4 regulatory functions of Ca2+?
- Ca++ can be passed across cell membranes
- Ca++ provides intracellular signals
- Ca++ is a famous secondary messenger
- Ca++ can switch metabolic reactions on and off
What are 2 structural roles of Ca2+?
- Ca++ is found in bones and in teeth
- Ca++ has a structural role in proteins
What is Calmodulin?
A protein which binds calcium (4) and is involved in regulating a variety of activities in cells
What 2 structures make up the bone?
Hydroxyapetite and Collagen
What forms kidney stones and how can it be prevented?
Ca-Oxalate
* Pervented with a low oxalate diet
What forms egg shells?
Ca-Carbonate
What carbonate is found in bones and teeth?
Ca-Phosphate
What are the main 3 roles of Mg2+?
- Required in enzymes that bind to nucleotides (polymerases)
- Required for catalysis
- Present in chlorphyll
