Science

• Respiratory system


  Also known as the human breathing system, responsible for taking in oxygen and expelling carbon dioxide
• Parts of the respiratory system

  • Nose and mouth
  • Nasal cavity or nasal passageways
  • Pharynx
  • Larynx
  • Trachea
  • Lungs
  • Bronchi
  • Bronchioles
  • Alveoli
• Inhalation


  1. Oxygen enters the body

  2. Ribs move out, chest space increases

  3. Diaphragm muscle contracts, moves down
• Exhalation


  1. Carbon dioxide exits the body

  2. Ribs move in, chest space decreases

  3. Diaphragm muscle relaxes, moves up
• Circulatory system


  Also known as the cardiovascular system, the life support structure that nourishes cells and delivers materials in the body
• Major parts of the circulatory system

  • Heart
  • Blood vessels (arteries, veins, capillaries)
  • Blood
• The heart is a hollow muscle as big as your fist
• Parts of the heart

  • Right atrium
  • Left atrium
  • Right ventricle
  • Left ventricle
  • Tricuspid valve
  • Bicuspid valve
  • Pulmonary valve
  • Aortic valve
  • Superior vena cava
  • Inferior vena cava
  • Pulmonary artery
  • Pulmonary vein
  • Aorta
• Circulatory system function


  Air enters lungs, goes to left side of heart, pumped through body, carbon dioxide goes to right side of heart, expelled through lungs
• Types of circulation


  • Pulmonary circulation
  • Coronary circulation
  • Systemic circulation
• Heredity


  The transmission of genetic characters from parents to offspring. It is a natural process by which the sum of the characteristics and potentialities are genetically derived or passed from one generation to the next.
• Inheritance


  The acquisition or reception of genetic qualities/appearance by offspring in sexual reproduction. The genetic materials of two parents is combined and passed on to one individual.
• Genetic variation


  The differences between individuals or the differences between populations. It is a state of having different traits and characteristics.
• Phenotype


  The observable physical properties of an organism, including appearance, development, and behavior.
• Genotype


  An organism's complete set of heritable genes or genes that can be passed down from parents to offspring.
• Alleles


  Any of the alternative forms of a gene in a genotype.
• Dominant traits


  Inherited characteristics that appear in an offspring if contributed from a parent through a dominant allele, represented by capital letters.
• Recessive traits


  Weak, unexpressed traits of a pair of alleles that have no effect on the phenotype of the heterozygous individual, represented by small letters.
• Homozygous traits


  Traits made up of two same alleles, represented by either all capital or all small letters.
• Heterozygous traits


  Traits made up of two different alleles, represented by a combination of capital and small letters.
• In a family, the father has tall height (dominant trait)


  The mother has short height (recessive trait)
• The child possesses the tall height characteristics of the father
• The mother's short height trait is an example of a recessive trait