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TRANSPORTCIRCULATORY SYSTEM
IN BODY DEFENCE
MECHANISM
BODY DEFENCE MECHANISM
To protect body against pathogens (disease-causing MO) that may enter.
Transmission of pathogens: Air Contaminated food Animal vectors Contact
patho: diseasegens: agents
LINES OF NATURAL DEFENCE
First Line
Second Line
Third Line
FIRST LINE OF DEFENCE
Prevention of pathogens entering the body by mean of physical and chemical barriers. Skin
Sweat Sebum
Tears and saliva Mucous membranes
Skin A physical barrier It has dead keratinised
layer that is hard to penetrate
Continual shedding of dead skin cells prohibit growth of pathogens
If there is a cut, the blood clots quickly to seal the wound To prevent blood loss
and entry of pathogens
Sweat and Sebum
Produced by skin as chemical barrier
Protective film over skin Acidic sebum secreted
by sebaceous glands contain lysozymes, which destroy cell walls of certain bacteria
Tears and Saliva
Tears and saliva contain lysozymes, which destroy bacteria (protect eyes and mouth)
Mucous Membranes Lines trachea, respiratory passageways, digestive
and urogenital tracts.
Mucous Membranes: Methods of Defense Mucus secreted in the nasal cavity and
trachea traps dust particles and microbial spores contains lysozyme to destroy bacteria
The cilia in the respiratory tract sweep the trapped particles to the pharynx.
The hydrochloric acid in gastric juice can kill many microorganisms
SECOND LINE OF DEFENCE
The non-specific killing action by phagocytic WBC (e.g. neutrophil-blood, macrophages-IF; some dissolved e.g. venom and toxin).
They are attracted by chemicals produced at the sites of infection, engulf and ingest MO or other particles (like debris) by phagocytosis.
Some phagocytes may also be destroyed by toxins of pathogens.
THIRD LINE OF DEFENCE
Immune System System triggered in response to the presence
of foreign substance (antigen = proteins / polysaccharides usually found on cell membrane of MO or foreign tissues) in our body.
Specific / targeted response Immunity
The state which the body is resistant to infections by pathogens
Lymphocyte
Lymphocytes B Lymphocytes –
produce antibody T Lymphocytes –
attack infected cells or secrete certain chemicals to coordinate immune response
Antibody
Protein produced by lymphocytes in response to the entry of an antigen into the body.
Each type of antibody is specific to a particular antigen.
They help to destroy pathogens in different ways.
Types of Antibody Action Neutralisation – neutralizes toxins Agglutination – binds to surface of antigens and
cause clumping of bacteria cells Opsonisation – binds to surface of antigens to
stimulate phagocytosis by macrophages Lysis – binds to surface of antigens to form pores
on cell membrane, which leads to cell rupture
Memory Lymphocyte
After recovery, some lymphocytes remain for a period of time. Memory lymphocytes
Defend against future infection. Infection by the same type of antigen
Therefore, we are immune against particular diseases. Immunity – ability of organism to resist infection
by pathogens or their toxin effects.
Naturally Acquired Active Passive
Artificially acquired Active Passive
TYPES OF IMMUNITY
Types of immunity
Active natural immunity Active natural
acquired immunity: acquired after a person recovers from an infection.
Eg; measles or chickenpox.
Active artificial immunity Active artificial
acquired immunity: Eg; vaccine (contains
killed or weakened antigens).
Active because the a/bodies produced by the body itself
Artificial because it is obtained through vaccination. the process is known as immunisation.
Artifi
cial a
ctiv
e im
mun
ity
Passive immunity1. Passive natural immunity: when
a/bodies from the mother transported across the placenta to the foetus. Lasts for a few months.
2. Passive artificial immunity: injecting antiserum containing a specific a/bodies prepared from human/animal’s blood.
Passive artificial immunity Usually used to treat
patient with serious ill. Eg: rabies, tetanus or snake bites
Give temporary immunity.
Artificially acquired passive immunity
QUIZZES
Which of the following describes the first line of defence? Antara yang berikut, yang manakah menerangkan tentang barisan pertahanan pertama?
A. It involves lymphocytes in the blood Ia melibatkan limfosit dalam darah
B. It involves phagocytic white blood cells Ia melibatkan sel darah putih yang bersifat fagositik
C. It involves skin and mucous membranes Ia melibatkan kulit dan membrane mucus
D. It produces antibodies that destroy bacteria and viruses. Ia menghasilkan antibody yang memusnahkan bakteria dan virus
Which of the following substances is injected into the body to stimulate antibody production? Antara bahan berikut, yang manakah disuntik ke dalam badan se orang untuk merangsangkan penghasilan antibody? A. Serum B. Vaccine C. Antibody D. Antiserum
. Which of the following belong to the first line of defence? Antara yang berikut, yang manakah terlibat dalam barisan pertahanan yang pertama? A. Hydrochoric acid Asid hidroklorik B. Phagocytes Fagosit C. Antibodies Antibodi D. Macrophages Makrofaj
What is the antibody mechanism shown in Diagram 4? Apakah mekanisma antibody yang ditunjukkan di Rajah 4?1
1 Diagram 4/ Rajah 4
A. Lysis C. Opsonisation Lisis Opsonisasi B. Agglutination D. Neutralization Aglutinasi Peneutralan
Based on the diagram, what is the mechanism used by antibodies to destroy the antigen? Berdasarkan Rajah apakah mekanisme yang digunakan oleh antibody untuk memusnahkan antigen?
A. Lysis C. Opsonisation Lisis Opsonisasi B. Neutralization D. Agglutination Peneutralan Aglutinasi
Diagram 1 shows two microorganisms which enter the human body by chance. Rajah 1 menunjukkan dua mikroorgansma yang memasukki badan manusia secara kebetulan.
Diagram 1 / Rajah 1 Which parts of the these microorganisms are responsible in stimulating the immune response and produce antibodies against them? Bahagian mikroorganisma manakah yang bertanggungjawab untuk merangsang tindak balas keimunan dan menghasilkan antibody untuk menentang sesame sendiri?
A. P and R B. P and S C. Q and R D. Q and S
Diagram 2 is a graph which shows the amount of antibodies in the blood after two injections of compound X. Rajah 2 merupakan satu graf yang menunjukkan jumlah antibodi dalam darah selepas dua suntikan sebatian X.
Diagram 2/Rajah 2
Which of the following describes the compound X and the type of immunity in Diagram 2? Antara yang berikut, yang manakah menerangkan sebatian X dan jenis keimunan dalam Rajah 2?
Diagram 2 is a graph which shows the amount of antibodies in the blood after two injections of compound X. Rajah 2 merupakan satu graf yang menunjukkan jumlah antibodi dalam darah selepas dua suntikan sebatian X.
Diagram 2/Rajah 2
Which of the following describes the compound X and the type of immunity in Diagram 2? Antara yang berikut, yang manakah menerangkan sebatian X dan jenis keimunan dalam Rajah 2?
Which of the following graphs shows the immunity developed after vaccination? Antara graf berikut, yang manakah menunjukkan keimunan berlaku selepas pemvaksinan?
Which of the following graphs shows the immunity developed after vaccination? Antara graf berikut, yang manakah menunjukkan keimunan berlaku selepas pemvaksinan?
5 . Passive immunity against tetanus is acquired by injection with an anti-serum. Keimunan pasif terhadap tetanus didapati melalui suntikan dengan anti-serum. Which of the following reasons explain the statement? Antara sebab berikut,yang manakah menjelaskan pernyataan di atas? A. The anti-serum becomes effective immediately. Anti-serum member kesan dengan serta-merta B. The anti-serum kills many different kinds of bacteria Anti-serum membunuh berbagai jenis bakteria C. The effect of the immune serum is very long lasting Kesan sistem keimunan adalah berjangka panjang D. The immune system is stimulated to produce antibodies Sistem keimunan terangsang untuk menghasilkan antibody
Graph 1 shows a type of immunity. Graf 1 menunjukkan sejenis keimunan.
Which of the following statements is true about the graph? Antara pernyataan berikut, yang manakah benar tentang graf tersebut? A. Both injections contain serum that can raise antibody level. Kedua-dua suntikan mengandungi serum yang boleh meningkatkan aras antibody B. Second injection is required to boost level of immunity Suntikan kedua diperlukan untuk meningkatkan aras keimunan C. Both injections contain pathogens which can control production of antibody Kedua-dua suntikan mengandungi pathogen yang mengawal penghasilan antibodi D. Second injection contains higher level of antibody Suntikan kedua mengandungi aras antibody yang lebih tinggi
AIDS (acquired Immunodeficiency Syndrome)HIV virus
The effects of HIV Attacks the central nervous system & helper
T in the body’s immune system
Helper T are essential to activate other lymphocytes in antibody production.
Immune system become weakened & defenseless against pathogen
HIV Replication
Effects
Symptoms
“Some people get fever, headache, sore muscles and joints, stomach ache, swollen lymph glands, or a skin rash for one or two weeks. Most people think it's the flu. Some people have no symptoms” (AIDS.ORG 2003). In the later stages of HIV symptoms may include: Persistent, unexplained fatigue Soaking night sweatsShaking chills or fever higher than 100 F for several weeks Swelling of lymph nodes for more than three months Chronic diarrhoea Persistent headaches
The patients does not die from AIDS itself but from other secondary infection such as: Pneumonia Meningitis bacterial infection of the membranes covering the brain and
spinal cord (meninges).
Tuberculosis Fungal infection Cancer like Kaposi’s sarcoma
Transmission
Salt Blood pressureHypertension Sedentary obesity
How can you avoid infection?
Avoid casual sexual relationship
Live a responsible and healthy lifestyle
Do not share needle and other personal item
Educational programme
World AIDS Day 1st Dec
Appreciating a healthy cardiovascular system
CV disorders (eg.) Anemia (ah-NEE-me-yah): Diseased condition in which there is a
deficiency of red blood cells or hemoglobin. Arteriosclerosis (ar-tir-ee-o-skle-ROW-sis): Diseased condition in which
the walls of arteries become thickened and hard, interfering with the circulation of blood.
Atherosclerosis (ath-a-row-skle-ROW-sis): Diseased condition in which fatty material accumulates on the interior walls of arteries, making them narrower.
Hemophilia (hee-muh-FILL-ee-ah): Inherited blood disease in which the blood lacks one or more of the clotting factors, making it difficult to stop bleeding.
Hypertension (hi-per-TEN-shun): High blood pressure. Leukemia (loo-KEE-mee-ah): Type of cancer that affects the blood-
forming tissues and organs, causing them to flood the bloodstream and lymphatic system with immature and abnormal white blood cells.
Sickle cell anemia (SICK-el cell ah-NEE-me-yah): Inherited blood disorder in which red blood cells are sickle-shaped instead of round because of defective hemoglobin molecules.
Appreciating a healthy CV system Stick to a nutritious, well-balanced diet. Control your blood pressure. Control blood cholesterol. Prevent and manage diabetes. Quit smoking. Minimize stress.
An electron micrograph scan of a human aortic valve. The aorta is the main artery of the systemic circulation. (Photograph by P. Motta. Reproduced by permission of Photo Researchers, Inc.)