SCIENCEQ1

• 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, oxygen processed by cells, carbon dioxide returned to right side of heart, expelled through lungs
• Types of circulation


  • Pulmonary circulation
  • Coronary circulation
  • Systemic circulation
• The circulatory system circulates vital elements like oxygen and nutrients, and transports waste away from the body
• Lifestyle can affect the functioning of the respiratory and circulatory system
• Unhealthy lifestyle weakens the systems and increases the risk of diseases
• Cigarette smoking


  • Increases the risks of having different diseases and infections in the whole body
  • Causes lungs to appear dark and muddled, and heart to be enlarged
• Good health


  A state of complete physical, mental and social well-being, not just the absence of disease or illness
• Examples of healthy lifestyle practices


  • Balanced diet
  • Regular exercise
  • Enough rest and sleep
  • Staying hydrated
  • Reducing stress
• Washing hands with soap and water removes virus, bacteria and other microorganisms
• Negative lifestyle weakens the system, while healthy lifestyle leads to complete wellness
• Living a healthy lifestyle can help prevent chronic diseases and long-term illnesses
• Feeling good about yourself and taking care of your health are important for self-esteem and self-image
• Genetics


  A branch of biology concerned with the study of genes, genetic variation, and heredity in organisms
• Inheritance


  The process by which genetic information is passed on from parents to child
• Variation


  Any difference between cells, individual organisms, or groups of organisms of any species
• Gene


  A unit of heredity, a section of DNA that codes for a specific trait
• Genotype


  The genetic makeup of an organism, the combination of two alleles
• Phenotype


  The physical appearance, feature or trait of an organism
• Homozygous


  Having two identical alleles
• Heterozygous


  Having two different alleles
• Punnett square


  A graphical representation of the possible genotypes of an offspring arising from a particular cross or breeding event
• Gregor Mendel is considered the father of genetics for his principles that form the base for the understanding of heredity and variation
• Non-Mendelian inheritance


  A type of inheritance where the patterns of phenotypes do not coincide with those presented in Mendelian laws of inheritance
• Incomplete dominance


  • One allele does not completely dominate another allele, resulting in a new or third phenotype
• Incomplete dominance


  • Red snapdragon flower crossed with white snapdragon flower results in pink snapdragon flower
• Codominance


  • Both alleles are expressed equally in the phenotype of the heterozygote
• Codominance


  • Red flower crossed with white flower results in red and white flower
• Multiple alleles


  A gene that is controlled by more than two alleles
• Sex chromosomes


  The 23rd pair of chromosomes that determines gender, with females having XX and males having XY
• Sex-linked traits


  • Inherited through the X chromosomes
• Sex-linked trait


  • Pattern baldness
• Sex determination


  If an egg is fertilized by a sperm carrying a Y chromosome, the baby will be male. If an egg is fertilized by a sperm carrying an X chromosome, the baby will be female.