Biomolecules and Chemical Reaction

Types of Waves

• Electromagnetic waves (EM waves) are created by vibrations between electric and magnetic fields
• Mechanical waves require a medium to propagate

Electromagnetic Waves

• Types:
  • Radio waves (longest wavelength)
  • Microwaves
  • Infrared (IR)
  • Visible light
    • Colors of visible light:
      • Red
      • Orange
      • Yellow
      • Green
      • Blue
      • Violet
  • Ultraviolet (UV)
  • X-ray
  • Gamma Ray (shortest wavelength)

Properties of Electromagnetic Waves

• Can travel through vacuum at a speed of 3x10^8 m/s
• Energy is carried as they propagate
• Can travel through anything or vacuum, no medium needed
• Short wavelength = High Frequency, Long wavelength = Low Frequency

Uses of Electromagnetic Waves

• Radio waves:
  • Radio/Television Signals
  • Global Positioning System (GPS)
  • Magnetic Resonance Imaging (MRI)
• Microwaves:
  • Satellite Communication
  • Cellular phones (Terrestrial Communication)
  • Cooking
  • RADAR
• Infrared (IR):
  • Remote Control (IR remote)
  • Thermal Imaging
• Visible Light:
  • Artificial Lights (flashlight, lamp, etc.)
  • Gives light to electronic devices' screens
  • Optical Fibers
• Ultraviolet (UV):
  • Security Markings
  • Fluorescence
  • Sterilization
• X-ray:
  • Diagnosing Bone Fractures
  • Airport security scanner
• Gamma Ray:
  • Radiotherapy
  • Sterilize surgical instruments

Mechanical Waves

• Types:
  • Transverse Wave (moves in right angle direction)
  • Compressional or Longitudinal wave (vibrates parallel to motion of pulse, transfers sound)
• Two types of Longitudinal waves:
  • Compression: Close together
  • Rarefaction: Spread apart

Wave Properties

• Frequency: Measured by how many complete waves pass a fixed point in a certain amount of time
• Wave speed (r): Wave speed (m/s) = Frequency (Hz) x Wavelength (m)
• Speed of wave = Wavelength (m)/time (s)
• λ=Vxt, f=1/t
• t=1/f, c=fxt

Reflection, Refraction, Diffraction, and Interference

• Reflection: When an object or wave hits a surface through which it cannot pass, it bounces back
• Refraction: Bending of waves due to change of speed
• Diffraction: Wave moves around/through an opening in a barrier, it bends and spreads out
• Interference: Occurs when two or more waves meet while traveling through the same medium
  • Constructive Interference: Combine wave, continues
  • Destructive Interference: Crest meets trough, cancel each other

Endocrine Gland

• Anterior Pituitary:
  • Follicle Stimulating Hormone (FSH): Stimulates follicular growth in ovaries
  • Luteinizing Hormone (LH): Stimulates follicular growth in ovaries
• Ovaries:
  • Estrogen: Thickens endometrium
  • Progesterone: Thickens endometrium

Male Reproductive System

• Primary Hormones:
  • Follicle-stimulating hormone (FSH): Necessary to produce sperm
  • Luteinizing hormone (LH): Necessary to continue spermatogenesis
  • Testosterone: Main sex hormone in males
• Male reproductive parts:
  • Penis: Organ used for urination and intercourse
  • Scrotum: Holds testes in place
  • Testes: Produces sperm and testosterone

Protein Synthesis

• Transcription:
  • RNA polymerases combine nucleotides to form an RNA strand using one DNA strand as a template
• Translation:
  • Codes in the messenger RNA are translated to a polypeptide that contains specific amino acids
  • Amino acid bonds with each other to form polypeptides, which make up proteins
  • Three stages: Initiation, Elongation, and Termination

Mutations

• Changes to a DNA sequence
• Gene mutation: Point mutation (deletion, addition, or alteration of a single nucleotide base)
  • Nonsense mutation: Results in the formation of a stop codon
  • Missense mutation: When one nitrogenous base of the DNA is replaced, resulting in an altered codon

Nucleic Acids

• Two main classes: Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA)
• Polynucleotides composed of nucleotides
• Nucleotides consist of a nitrogenous base, pentose sugar, and phosphate group
• A and G are purines, while C, T, and U are pyrimidines

Types of Chemical Reactions

• Combination or Synthesis: A + B → AB
• Decomposition: AB → A + B
• Single Displacement (Replacement): AB + C → AC + B
• Double Displacement (Replacement): AB + CD → AD + CB
• Combustion (Burning) Reaction: Oxygen gas combines with a hydrocarbon, forming carbon dioxide and water