Essential Idea:   The human body has structures and processes that resist the continuous threat of invasion by pathogens.
At SHS, Topic 6.3 is taught in the following class unit(s):​​​​​​​​
6.3.U1  The skin and mucous membranes form a primary defense against pathogens that cause infectious disease.
  • Define pathogen.
  • State that skin and mucous membranes form the first line of defense against pathogens.
  • Outline the role of skin, sebaceous glands and mucous membranes in the defense against pathogens.​
6.3.U2  Cuts in the skin are sealed by blood clotting.
  • State two benefits of blood clotting when skin is cut.​
6.3.U3  Clotting factors are released from platelets.
  • Outline two roles of platelets in the blood clotting cascade.​
6.3.U4  The cascade results in the rapid conversion of fibrinogen to fibrin by thrombrin.
  • Describe the blood clotting cascade, including the role of platelets, clotting factors, thrombin, fibrinogen and fibrin.
6.3.U5  Ingestion of pathogens by phagocytic white blood cells gives non-specific immunity to diseases.
  • State the white blood cells are the second line of defence against pathogens.
  • Outline the function of phagocytic white blood cells in defense against pathogens.​
6.3.U6  Production of antibodies by lymphocytes in response to particular pathogens gives specific immunity.
  • Define “specific immune response.”
  • Contrast antigen and antibody.
  • Describe the structure and function of antibodies.
  • State the function of plasma cells and memory cells.​
6.3.U7  Antibiotic blocks processes that occur in prokaryotic cells but not in eukaryotic cells
  • Define antibiotic.
  • Outline the mechanisms by which antibiotics kill bacteria.
  • Explain why antibiotics are ineffective against viruses.​
6.3.U8  Viruses lack a metabolism and cannot therefore be treated with antibiotics.
  • Explain why antibiotics are ineffective against viruses.
6.3.U9  Some strains of bacteria have evolved with genes that confer resistance to antibiotics and some strains of bacteria have multiple resistance.​
  • List five measures that can be taken to avoid the development of antibiotic resistance.
  • Explain why multiple drug antibiotic resistance is especially dangerous.
  • State an example of a multidrug resistant bacteria.
6.3.A1  Causes and consequences of blood clot formation in coronary arteries.
  • State the function of the coronary arteries.
  • Define coronary thrombosis.
  • List sources of arterial damage that increase the risk of coronary thrombosis.
  • List factors that are correlated with an increased risk of coronary thrombosis and heart attack.
6.3.A2  Effects of HIV on the immune system and methods of transmission.
  • Describe the consequences of the HIV on the immune system.
  • Outline the relationship between HIV and AIDS.
  • List ways the HIV virus is spread.
6.3.A3  Florey and Chain’s experiments to test penicillin on bacterial infections in mice.
  • Explain methods and results of Florey and Chain’s experiments.​
6.3.NOS  Risks associated with scientific research- Florey and Chain’s tests on the safety of penicillin would not be compliant with current protocol on testing.
  • Compare allowable research risks of the past with those of the present.​
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