topic 1 - inorganic ions Flashcards
cgp (topic 1B) 23
what is an ion
an atom (or group of atoms) that has an electric charge
what is a cation
an ion with a positive charge
what is an anion
an ion with a negative charge
what is an inorganic ion
an ion which doesn’t contain carbon (although there are a few exceptions)
give three examples where inorganic ions can be found
in solution, in the cytoplasm of cells, in the body fluids of organisms
what is haemoglobin
a large protein that carries oxygen around the body in red blood cells
what ions are an important part of haemoglobin
iron ions
what is haemoglobin made up of
four different polypeptide chains - each with an iron ion (Fe2+) in the centre
why is Fe2+ important in haemoglobin
it binds to the oxygen in haemoglobin - when the oxygen is bound the Fe2+ ion temporarily becomes an Fe3+ ion until oxygen is released
what ions determine pH
hydrogen ions
how is pH calculated based on
the concentration of hydrogen ions (H+) in the environment
how do hydrogen ions affect pH
the more H+ present, the lower the pH (and the more acidic the environment)
what ions help transport glucose and amino acids across membranes
sodium ions (Na+)
what is co-transport
when a molecule of glucose or an amino acid is transported into a cell alongside sodium ions (Na+)
what ions are a essential component of ATP and DNA
phosphate ions
