Inorganic ions

• What are ions?

  An atom or group of atoms with an electric charge
• What is a cation?

  An ion with a positive charge
• What is the charge of a sodium ion (Na⁺)?

  +1
• What is the charge of a calcium ion (Ca²⁺)?

  +2
• What is an anion?

  An ion with a negative charge
• What is the charge of a chlorine ion (Cl⁻)?

  -1
• What is the charge of a phosphate ion (PO₄³⁻)?

  -3
• What defines an inorganic ion?

  It doesn't contain carbon, with few exceptions
• Where are inorganic ions found in organisms?

  In solution in cytoplasm and body fluids
• What determines the concentration of an ion in an organism?

  The specific role of the ion
• What role do iron ions (Fe²⁺) play in haemoglobin?

  They bind to oxygen in red blood cells
• What happens to Fe²⁺ when oxygen binds to it in haemoglobin?

  It temporarily becomes Fe³⁺
• How is pH related to hydrogen ions (H⁺)?

  More H⁺ means lower pH and more acidity
• How do sodium ions (Na⁺) assist glucose and amino acids?

  They help transport them across cell membranes
• What is co-transport in relation to sodium ions?

  Transporting glucose or amino acids with Na⁺
• What is a phosphate group?

  A phosphate ion attached to another molecule
• Which molecules contain phosphate groups?

  DNA, RNA, and ATP
• What is the role of phosphate groups in ATP?

  They store energy through their bonds
• How do phosphate groups contribute to DNA and RNA?

  They allow nucleotides to join to form polynucleotides
• What are the key roles of inorganic ions in organisms?

  • Carry oxygen (iron ions in haemoglobin)
  • Affect pH (hydrogen ions)
  • Assist in transport (sodium ions)
  • Form part of nucleic acids (phosphate ions)
• What are the differences between cations and anions?

  • Cations: positively charged ions
  • Anions: negatively charged ions