Elements and compounds (lesson notes)

• What are the main elements that make up an organism's body?

  Oxygen, Carbon, Nitrogen, Calcium, and Phosphorus
• What is the role of iron in the body?

  Iron is the main constituent of haemoglobin, which transports oxygen in red blood cells
• Why is calcium important for the body?

  Calcium is essential for muscle contraction
• What is the significance of nitrogen in the body?

  Nitrogen is the main part of amino acids
• What does the term 'ate' refer to in chemistry?

  'Ate' refers to oxygen, or something oxygenated
• What are macronutrients and their significance?

  • Macronutrients include iron, magnesium, phosphate, and calcium
  • Needed in small traces within the body
  • Phosphate groups make up DNA, RNA, and ATP (the universal energy currency)
  • Magnesium is essential for healthy bone growth and chlorophyll production in plants
• What happens if there is a lack of magnesium in plants?

  A lack of magnesium leads to yellow leaves and 'chlorosis', preventing photosynthesis
• What are micronutrients and examples of them?

  • Micronutrients include zinc, manganese, and iodine
  • Needed in minuscule amounts
• What are the basic building blocks of all substances?

  All substances are made from atoms of elements
• How are molecules formed?

  Molecules are made from two or more atoms
• What defines a molecule as an element?

  If the atoms in the molecule are the same, then the molecule is an element
• What defines a molecule as a compound?

  If the atoms are different, then the molecule is a compound
• What are ions and how can they be charged?

  Ions can be positively or negatively charged
• What are negatively charged particles that have gained one or more electrons called?

  Anions
• What is the overall charge of an anion?

  Negative charge
• What happens to an atom when it becomes a positively charged ion?


  It has lost one or more electrons and has more protons than electrons
• What are compounds made from?

  Atoms of two or more elements
• What distinguishes ionic compounds from molecular compounds?

  Ionic compounds are made of charged particles, while molecular compounds consist of non-charged particles
• Why do positively charged ions have an overall positive charge?

  Because they have more protons (positive charge) than electrons (negative charge)
• What is the solubility characteristic of non-polar compounds?

  They do not dissolve in water but will dissolve in lipids
• What are pure substances divided into?

  Elements and compounds
• What is required to break down pure substances into smaller parts?

  A chemical nuclear reaction
• What are the six common elements that account for 99% of the mass of the human body?

  Oxygen, Carbon, Hydrogen, Nitrogen, and two others
• What percentage of the human body mass is made up of Nitrogen?

  3%
• What are the main components of all organic molecules?

  Carbon, Hydrogen, and Oxygen
• In which types of molecules are Carbon, Hydrogen, and Oxygen found?

  Amino acids and nucleic acids
• What are the functions of the six common elements in the human body?

  • Oxygen: Essential for respiration
  • Carbon: Backbone of organic molecules
  • Hydrogen: Component of water and organic compounds
  • Nitrogen: Key element in amino acids and nucleic acids
• What percentage of the human body mass is calcium?

  2%
• What is the function of calcium in the body?

  It strengthens teeth, bones, and nerves in animals, and cell walls in plants.
• Where is calcium present in the body?

  In cell membranes, ATP, and nucleic acids.
• What percentage of the human body mass is potassium?

  0.35%
• What is the function of potassium in the body?

  Nerve impulse transmission.
• What percentage of the human body mass is sulfur?


  0.25%
• What role does sulfur play in the body?

  It is a component of some amino acids.
• What is the function of chlorine in the body?

  It is involved in carbon dioxide transport.
• What is the function of sodium in the body?

  Nerve impulse transmission.
• What is the function of magnesium in the body?

  It is involved in enzyme function and chlorophyll function in plants.
• What is the function of iron in the body?

  It is essential for oxygen transport.
• What is the function of copper in the body?

  It is involved in enzyme function.
• What is the function of manganese in the body?

  It is involved in enzyme function.