Pathogens and immune response Flashcards
What are pathogens and give examples of them
Pathogens are organisms that cause disease
e.g , Protoctista, viruses, fungi, bacteria
What are examples of viruses in Plants and animals
Plants- Tobacco mosaic Virus
Animals- Influenza viruses “flu” and HIV/AIDS
What are examples of bacteria in plants and animals
Animals- Salmonella
Plants- Agrobacterium
What are examples of Fungi in plants and animals
Plants- Black rose spot
Animals- Athlete’s foot
What are examples of Protists in plants and animals
Plants- Downy mildew
Animals- Malaria ( Plasmodium)
What are the body’s two defence mechanisms
Barrier mechanism- prevent pathogens entering body
Immune response- once pathogens entered body how does body respond
what are examples of White blood cells and when are they used
Phagocytes
lymphocytes
used int he bodies immune response
what is the largest barrier method of the body
Skin
prevents pathogens from entering the body
what do phagocytes do
Able to change shape and engulf pathogen
engulf and digest (using enzymes) pathogens
what is the job of lymphocytes
Produce antibodies
What are the four main components of the blood
Plasma
Platelets
Red Blood cells
White Blood cells
What is Plasma
Plasma is the pale yellow liquid which carries just about everything
e.g
carbon dioxide from the boy cells to the lungs
Hormones
Heat energy
Red, white blood cells
Platelets
Digested food products
What are Platelets
small white fragments which help the blood clot
How do Platelets work
When you damage a blood vessel, platelets clump together to plug the damage
this is known as blood clotting
What are the benefits of blood clotting
Prevents you from loosing too much blood and prevent
microorganisms from entering
What is the job of red blood cells
Carry oxygen to the working mucscles
How to RBC carry out their job
by being well adapted to it’s function
- small and have a biconcave shape : to gain a large SA: Vol ratio for absorbing and releasing oxygen
- contains Haemoglobin which gives blood it’s colour and contains lots of iron
- no nucleus to free up space for more haemoglobin to bind to increase the oxygen carrying capacity
How does producing antibodies help kill pathogens
Antibodies are specific
they lock on to the invading pathogens and mark them out for destruction if other WBC
Antibodies are then produced rapidly and flow around he body to mark similar pathogens
memory cells are produced
What are memory cells
Mermory cells are also produced in response to pathogens
these remain in the body and remember a specific pathogen/ antigen
they can reproduce fast if the same antigen enters the body again.
this explains why you are immune to most diseases if you already had them.
Explain how vaccination protects from future infections
Vaccination reduces the time you get ill for
vaccinations usually consist of injecting dead or inactive pathogens into the body
they still trigger a immune response even though they are harmless
lymphocytes produce antibodies to attack them
Memory cells are produced and will remain in the body
so if live pathogens of the same type ever appear the antibodies remember the antigen and reproduce much faster to kill them
reducing the severity of your illness
