B17: Disease Flashcards
Define disease
disease is a condition that impairs the normal functioning of cells, tissues and organs thereby damaging the health of the body
what are the 4 main types or categories of disease?
- Hereditary
- Deficiency
- Pathogenic
- Physiological
what is a hereditay disease?
Give 2 examples
Disease caused by an abnormal gene which passes from one generation to another
examples: sickle cell disease, haemophilia,
what is a deficiency disease? Give examples
Deficiency disease is a disease caused by lack of a nutrient in the diet
examples: Scurvy, anaemia, Kwashiorkor,
what is a pathogenic disease?
Give 4 examples
A pathogenic disease is when harmful organisms(viruses, bacteria, fungi, protozoa) invade the body.
Examples: AIDS, Syphilis, Mumbs, Dengue, Yellow Fever, Malaria
What is a physiological disease?
Give 4 examples.
A physiological disease is a disease cause by malfunctioning of the organs of the body.
Examples: Hypertension; diabetes; cancer, Parkinsons disease; stroke; heart disease
what is a vector?
Give 4 examples of vectors
a vector is an organism that carries pathogens in or on its body from person to person but itself not being affected.
- houseflies
- mosquitos
- rats
- fleas
What are the 2 broad categories of disease?
- Communicable: caused by pathogens and pass from one person to another.
- Non-commnicable diseases: cannot pass from on person to another. Hereditary, physiological and deficiency diseases are non-communicable diseases.
Diagram showing the life cycle of a mosquito.
Name the process whereby a mosquito egg becomes a full grown mosquito.
complete metamorphosis
Label the life cycle of the mosquito
what is metamorphosis?
complete metamorphosis is a complete change in the appearance of an organism during its growth and development
which stage of the mosquito life cycle requires water
egg, lavra, pupa
which stage of the misquito life cycle is known as the reproductive stage?
the adult stage
which stage of the mospquito life cycle is known as the feeding and growing stage?
the larva stage
what diseases are transmitted by mosquitoes?
- Malaria
- yellow fever
- dengue
- chikungunya
what are the 2 main types of mosquitoes involved in the transmission of tropical diseases and what disease do they transmit
- Anopheles mospuito: Malaria
- Aedes Mosquito: yellow fever, dengue, chikungunya
What is the primary host?
the target host ie the host that the pathogen makes ill.
what is the secondary host?
The intermediate host where the patogens reproduce without harming it, before moving to the primary host.
How many hosts do mosquito borne pathogens have
2 - misquito and humans
How does the mosquito trasmit pathogens from one person to another?
- the pathogens remain and multiply in the salivary glands of the female mosquitoes
- When the female mosquito bites someone they inject saliva into the blood to prevent clotting, so they can ingest it.
- the mosquito therefore passes the pathogens to that persons bloodstream when they inject the saliva.
What do we need to know about mosquitoes in order to control the spread of the diseases they trasmit?
their life cycle
How are mosquitoes contolled?
- Controlling Larva and Pupae stages
- Draining of standing water
- adding insecticides to the breeding areas of mosquitoes
- using fish that eat the larvae and pupae
- spraying oil or kerosene on the surface of the breeding areas to prevent the lavae and pupae from breathing
- Controlling the adult stage
* Spray with insecticides in houses and breeding sites
What is diabetes?
a physiological disease where the control of blood glucose is abnormal
what is hypertension?
Hypertension is a physiological disease in which the pressure in the arteries is higher that normal
name some factors that lead to Diabetes type II and Hypertension?
- Factors that lead to diabetes type II: diet high in fat and refined sugars; obesity.
- Hypertension: High salt diet, lack of exercise, stress
How can Diabetes and hypertension be controlled?
- healthy balanced diet
- regular exercise
How can the 4 main types of disease be treated/controlled
- Pathogenic disease: use of antibiotics, antivirals, antifungals, vaccination
- Deficiency disease: balanced diet; providing the deficient nutrients with dietary supplements
- Physiological: Healthy lifestyle, proper diet, excercise, treating with drugs to control the disease such as insulin in diabetes and antihpertensive drugs.
Definition of immunity
temporary or permanent resistance to pathogens
How does blood defend the body against disease?
- First line of defense clots formation after a wound
- Second line of defense - phagocytes ingest and kill the pathogens
- Third line of defense - production of antibodies by lymphocytes - gives immunity agains the pathogen
The 2 main types of immunity are
- natural
- artificial
pathogens include
viruses
bacteria
fungi
parasites
how antibodies work
- released by lymphocytes
- cause clumping together of the pathogens for phagocytes to engulf
- cause pathogens to desintegrate
- neutralize toxins produced by pathogens
what is artificial immunity?
immunity adquired by vaccination
importance of artificial immunity
controle the spread of communicable diseases
What a vaccine may contain
- live weakened pathogen eg measles, mumps, rubella vaccines
- Dead pathogens eg cholera, influenza, polio vaccines
- Toxins from the pathogen eg. Diphtheria and tetanus toxoid vaccines
- fragments of the pathogen eg influenza vaccine
- spacific antigens from the coat of the pathogen produced by genetic engineering eg hepatatis B vaccine.
babies have immature immune systems. how are they protected from pathogens?
the mother’s antibodies pass to child by crossing the placenta or in breast milk.
(1)____________ is a chemical that stimulates lymphocytes to produce (2)______________, which are (3) _____________ that attach to the (1)______________ on the pathogen. This attracts (4)__________ which engulf the pathogen and (5)_________ it within its (6)___________
- antigens
- antibodies
- proteins
- phagocytes
- digest
- Vacuoles
what is a vaccine?
a substance used to stimulate the production of antibodies and provide artificial immunity against diseases.
what is an antitoxin?
antibodies that neurtalize toxins
what is vaccination?
process by which vaccines are introduced in to the body to stimulate immunity against certain pathogens.
what is natural immunity ?
forms of defence we inherit, eg. blood clotting, phagocytosis
distinguish between specific immunity and nonspecific immunity
- specific immunity is not inherited. specific immunity is inherited
- Specific immunity involves lymphocytes, antibodies, antigens. Nonspecific immunity involves non-specific defences such as clotting of blood and phagocytes.
Types of immunity
Lines of defense against pathogens
classify immunity
