B6.3b Flashcards
How does a scab form and why is it necessary
1) protect against pathogens and stop bleeding out
Platelets are sensitive to oxygen, in the presence of this in a cut they:
- PLAYELETS change blood protein fibrinogen into fibrin , forming a network of Forbes in the cut. This is solid now.
2) here red blood cells are also trapped in the fibres. Forms the clot
3) over time clot hardens to form a scab, keeping skin clean and allowing it to heal. Once heralded it will fall off
What are the other non specific defences that body has?
Skin Cillia mucus HCL Eyes Nasal hair
Skin- Physical Barrier, in which the dead outer cells make it hard for pathogens to penetrate. Also produce antimicrobial substances by sweat glands that kill pathogens
Acid in stomach- HCL here kills pathogens in food
Cillis and mucus in airways
- respiratory tract lined with these that trap particles and waft back up to be swallowed
Eyes
- in tears prüfe enzyme lysozyme which break down bacteria on surface of eye
Nasal hairs= keep outs dust and large microorganisms
And skin…
Now what about how immune system attacks pathogens?
White blood cells in two types, how does phagocytosis work
PHAGOCYTES: engulf pathogens and make enzymes that digest them, called phagocytosis
LYMPHOCYTES: these make antitoxins and antibodies that attack pathogens alike
What are antigens
Molecules on pathogens
How do lymphocytes producing antibodies and antitoxins work?
What happens after they are killed?
What about antitoxins
When forgone antigens are detected, they will produce antibodies, proteins that are SPECIFIC to an antigen, and this takes some time to do as it is specific response.
- these are rapidly produced and cause antigens to group together making it easier for phagocytes to attack them in phagocytosis . They also Directly KILL THEM TOO
2) after they are killed, memory cells remmeber the antibody produced and stored a template for later on .Now if the same pathogen comes again, the lymphocytes will rapidly produce them and kill the, before they can cause illness- immunity .
3) they also produce antitoxins to counteract toxins by bacteria
What are monoclonal antibodies?
They are produced as clones from a single cell, therefore monoclonal. They can be used to target a specific chemical or cell.
How are they made (monoclonal) 6 marker?
1) first a Moshe is injected with an antigen (in a hormone/pathogen)
2) mouse immune system in next week will work on producing antibody this fits the antigen required. These will be found in the mouse’s B LYMPHOCYTES WHICH ARE EXTRACTED
3) As these can not divide easily and survive outside the body to produce more, they are fused with a MYELOMA. These are tumour cancerous cells which divide indefinitely. This fusion produces a hybrid : a hybridoma
4) these hybridomas clone as they divide indefinitely giving clones of the antibody , which are then harvested. And then purified
5) now can be used for things…
What ca no Nikon always antibodies be used form
Pregnancy testing
Detecting disease
Treating cancer
How do monoclonal antibodies used for detecting diseases
Why is this useful
The mocnoclonal antibdoies in the body act as markers. Here they bind to the prostrate gand cancer cell antigens for example and confirm its presence as they show a bright spot. Now under specific cameras the exact location of cancer cells are shown…
Good as it allows. For early diagnosis and higher chance of survival
How are mABs used for detecting pregnancy?
1) woman pregnant= human chronoic gonadotropin (hCG) is priced after TWO WEEKS OF CONCEPTION.
2) monoclonal antibodies have been produced that will bind to the antigens of this hCG protein causing a chemical COLUR CHANGE
3) when a woman urinated on the stick containing hCG monoclonal antibodies, colour change will take place auch that a line appears, confirming pregnancy
Man used in measuring and monitoring in sport and gps?
Used in sport to see if illegal drugs been used
GPS can use them to monitor hormone levels
How used to treat cancer mab?
What cancers are they used in
1) anti cancerb drugs can be attached attached to the monoclonal antibodies, and carry straight to the cancer cell avoiding healthy, these involve radioactive unsatnces , MORE EFFECTIVE
2) CAN also kill them or preventing them from receiving growth hormone and getting bigger
Used in breast stomach Bowel cancers…
Advantages disadvantages of monoclonal antibodies.
Why better than. Other cancer treatments
What are considerations
Mouse
1) initlslh known as magic bullets due to specificity. Here they can target cells without hurting others, favourable other radiotherapy for instance . Meaning hair won’t fall off, or nausea induced by radiotherapy…
2) being specific means extremely expensive
- difficult to attach chemicals to antibodies
- side effects there, due to them being developed by mice … and d inference of lymphocytes…
Unethical to use mouse too…
How do vaccines work and what do they contain
Vaccines contain small amounts of weakened or dead versions of a pathogen
- these carry a tigers, so even though harmless will still trigger and immune response
- memory cells will keep antibodies that had to be specifically produced against these pathogens, and they
Rosy does immediately - now when you catch the pathogens they will be destroyed even before they have a chance to make you sick. Your ar now immune
How do white blood cells detect foreign substances.
Antigens are kn al cells in body, so white blood cells recognise. As soon as foreign antigen comes, ropes. This is why cancer cells aren’t removed, as produced by own body…