Y3-THV3-Lesson 11 GKR

• Biologie
• Middelbare school
• havo, vwo
• Leerjaar 3

Homeostasis, Health & Disease

Lesson 11

This lesson

• Innate immunity
• Progress Pathogen project
  

PATHOGENS PROJECT

• How are you doing?
• Any questions so far?

Do not forget:

• Start writing your final report
• Submission date: October 25th 

Learning goals

• I understand the difference in innate and adaptive immune system
• I understand the difference in specific and aspecific immune system
• I can explain what barriers in the human body contribute to immunity
• I can explain how phagocytes contribute to immunity

Keywords

• Innate immunity
• Adaptive immunity
• Barrier function
• Phagocyte
• Phagocytosis
• Lymphatic system
• Lymph nodes 
  

Innate immunesystem

Innate immune system:

Parts of the immune system that are present from birth

Adaptive immunesystem

Adaptive immune system:

Parts and processes of the immune system that are changing based on previous experiences

Lines of defence

Immune system counters attacks from pathogens in three lines of defense:

1. Barriers: keeping the pathogens out
2. Phagocytes: attacking and wiping out invaded pathogens 
3. Lymphocytes: learning from phagocytes how to specifically and effectively kill a certain type of pathogen

Lines of defence

Line 1: Barriers

Keeping pathogens out

Mechanical: Physical blockages preventing pathogens from entering the body

Chemical: Attacking pathogens by means of antimicrobial molecules

• skin
• mucosal membranes
• stomach acid
• antibacterial proteins

Line 1: Barriers

Mechanical Barriers           vs           Chemical Barriers

Physical blockages preventing pathogens from entering the body

Attacking pathogens by means of antimicrobial molecules

0

Line 2: Phagocytes

Phagocytes are able to perform phagocytosis

Line 2: Phagocytes

Phagocytes are able to perform phagocytosis and to present parts of the pathogen to the adaptive immune system

Different types of phagocytes

Dendritic cells

Macrophages

Neutrophils

Phagocytes that display parts of pathogen on there membranes for display and presentation

Phagocytes that patrol in tissues and kill off pathogens. They can be controlled by lymphocytes (line 3)

Phagocytes that kill off pathogens by killing themselves

Overview of line 2

Line 1 fails: pathogens invade the body

Surviving tissue cells call for help

Macrophages start to devour pathogens and send out signs

Neutrophils arrive and join the battle. They massively kill off the pathogens and themselves

Proteins of the complement system start to kill pathogens by perforating them

Dendritic cells display parts of the pathogens on their membranes and travel to the lymph nodes

Activation of defence line 3: the adaptive immune system - the lymphocytes

Lymphatic system

Sewage system of the body

• Lymph vessels, lymph nodes, bone marrow, spleen and thymus
• drained tissue fluid is sent to lymph nodes for screening
• here the dendritic cell presents its pathogen parts (antigens)

Inflamation

A reaction from the tissue to the signaling molecules

A concept map

A concept map adds descriptions to links between two terms

To what part of the immune system do these lines of defence belong?

Innate immune system

Adaptive immune system

Barriers

Phagocytes

Lymphocytes

As part of innate immunity, the human body utilises mechanical and chemical immunity.
Which of the following is an example of chemical immunity?

1. Skin
2. Fluid flow in the urinary tracht
3. Stomach acid
4. Mucosal layer in the vagina

Explain how washing your skin with soap regularly is countering your immunity.

1

2

3

Surviving tissue cells are sending out distress molecules

Macrophages respond and start to devour the pathogens. They also send out other alarm molecules

Neutrophils respond and leave the blood vessels. They attack the pathogen by releasing toxic molecules and they kill themselves off

Inflammation causes a lot of discomfort. Still it is very useful: for what purpose does tissue get inflamed?

What is the main 'ingredient' of pus?

1. pathogens
2. macrophages
3. neutrophils

Learning goals

• I understand the difference in innate and adaptive immune system
• I understand the difference in specific and aspecific immune system
• I can explain what barriers in the human body contribute to immunity
• I can explain how phagocytes contribute to immunity

Keywords

• Innate immunity
• Adaptive immunity
• Barrier function
• Phagocyte
• Phagocytosis
• Lymphatic system
• Lymph nodes 
  

Homework for next time

• Study glossarie "YR3_CH10_HW 10" on StudyGo
  
• Work on the final report of the Pathogen Project