YR3_CH10_LSN10

• Biologie
• Middelbare school
• vwo
• Leerjaar 3

Practice Quiz on KWIZL:

• 8 min max practice quiz.
• 7 min max peer review and feedback.
• 5 min max write a reflection in your notebook:
• What mistakes did I make?
• Why were they mistakes?
• What can I do better next time?

CH.10: Health & Disease

LSN 10

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

Key Words:

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

Read pages 147 & 148 in your book and look for definitions of these words.

Innate immunesystem:

The parts of the immune system that are present from birth

Adaptive immunesystem:

The parts and processes of the immune system that are changing based on previous experiences.

Lines of defence:

The 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

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

Innate immune system

Adaptive immune system

Barriers

Phagocytes

Lymphocytes

Lines of defence:

Line 1: Barriers

Organs that keep pathogens out of our body:

• skin
• mucosal membranes
• stomach acid
• antibacterial proteins

Note locations in your body that are lined by a mucosal membrane

Line 1: Barriers

Mechanical Barriers           vs           Chemical Barriers

Physical blockages preventing pathogens from entering the body

Attacking pathogens by means of antimicrobial molecules

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.

Line 2: Phagocytes

Phagocytes are able to perform phagocytosis

Note the names of the different types of leukocytes that play a part in your innate immunity

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

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

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

Inflamation

a reaction from the tissue to the signaling molecules

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

Lymphatic system

lymph vessels, lymph nodes, bone marrow, spleen and thymus

sewage system of your body

drained tissue fluid is sent to lymph nodes for screening

here the dendritic cell presents its pathogen parts (antigens)

A concept map

A concept map adds descriptions to links between two terms

Homework for next time:

• Complete a concept map for CH7 & Ch10 till now
• Revise the glossaries on StudyGO (HW5-HW10)
• Revise all notes till now.