inorganic ions

Question 1

what is an ion

Answer 1

atom or group of atoms which carry a charge

Question 2

what is a positive ion

Answer 2

a cation

Question 3

what is an anion

Answer 3

a negative ion

Question 4

what is an inorganic ion

Answer 4

an ion which doesnt contain carbon

Question 5

how are iron ions an important part of haemoglobin

Answer 5

• haemoglobin is a large protein which carries oxygen around the body in red blood cells
• it is made up of four different polypeptide chains each with an iron ion in the centre
• its the iron that actually binds the ocygen to haemoglobin
• when oxygen is bound the Fe2+ turns to Fe3+ until the oxygen is released

Question 6

how do hydrogen ions determine pH

Answer 6

pH is calculated based on the concentration of hydrogen ions in the environment. the more hydrogen ions present, the lower the pH and a more acidic environment
- enzyme controlled reactions are all affected by pH

Question 7

how do sodium ions help transport glucose and amino acids across membranes

Answer 7

• glucose and amino acids need help to cross membranes
• a molecule of glucose or an amino acid can be transported into a cell across the cell surface membrane alongside sodium ions (cotransport)

Question 8

how are phosphate ions an essential component of ATP and DNA

Answer 8

• when a phosphate ion is attached to another molecule its known as a phosphate group
• DNA, RNA, and ATP all contain phosphate groups
• its the bonds between the phosphate groups which store all the energy in ATP
• the phosphate groups in DNA and RNA allow nucleotides to join up and form polynucleotides