BIOL111 L1

• What are the two types of energy mentioned in the lecture?

  Potential and kinetic energy
• What is the difference between potential and kinetic energy?

  Kinetic energy is energy of movement, while potential energy is energy due to position.
• How many naturally-occurring elements are there?

  92 naturally-occurring elements
• What is an element?

  An element is a substance that cannot be broken down into other substances by chemical reactions.
• What four elements make up 96% of living matter?

  Carbon (C), oxygen (O), hydrogen (H), and nitrogen (N)
• What are trace elements, and can you name two?

  Trace elements are elements required in small amounts, such as iron (Fe) and iodine (I).
• What is the smallest unit of matter that retains the properties of an element?

  An atom
• What subatomic particles make up an atom?

  Protons, neutrons, and electrons
• What is the charge of protons and electrons?

  Protons have a positive charge, and electrons have a negative charge.
• How does the number of protons relate to the number of electrons in an atom?

  The number of protons equals the number of electrons in a neutral atom.
• What is the atomic number of an element?

  The atomic number is the number of protons in an atom.
• What is the atomic mass of hydrogen?

  1 Dalton
• What defines isotopes of an element?

  Isotopes have the same atomic number but different mass numbers.
• What are the types of atomic orbitals and their electron capacities?

  • 1s: 2 electrons
  • 2s: 2 electrons
  • 2p: 6 electrons
• Why are filled orbitals more stable than unfilled ones?

  Filled orbitals are more stable because they minimize energy and maximize electron pairing.
• What is a compound?

  A compound is a substance consisting of two or more elements in a fixed ratio.
• What is an example of a compound?

  Table salt (sodium chloride or NaCl)
• What are the four types of chemical bonds?

  1. Covalent
  2. Hydrogen
  3. Ionic
  4. van der Waals
• What is a covalent bond?

  A covalent bond is the sharing of electrons between two atoms.
• What is the strength of a hydrogen bond compared to covalent bonds?

  A hydrogen bond is weak compared to covalent or ionic bonds.
• How are ionic bonds formed?

  Ionic bonds are formed when two atoms with very different attractions for valence electrons come together.
• What is the strength of van der Waals forces?

  Very weak, about 0.5 kJ/mole
• What interactions hold proteins in their correct shape for function?

  • Hydrogen bonds
  • Ionic bonds
  • Hydrophobic interactions
  • van der Waals forces