Biology Stupied Questions Part 1 Flashcards
Explain primary defences are non-specific
So they can target and defend against all pathogens so they cannot enter the body
Why is it important that blood clots are no formed in the blood
Because the blood flows rate flow decrease then oxygen wont flow to the cells therefore respiration will not happen and the cells will die plus carbon dioxide wont be removed especially if in the heart this would cause a heart attack
Prothrombin is activated by the removal of amino acids explain how this can activate the enzyme
The amino acids are removed so pH is changed this causes a change in the shape of the active site enzyme and causes it activation
What are the symptoms relieved by the drug antihistamine
Reduction in inflammation
- less swelling
- less redness
- less pain
How is inflammation caused
Body senses an microorganism in the tissue via the mast cells this produces histamine this produced vascodialtion which increases the rate if blood flow this enlargement of the capillaries causes redness as they are closer to the skin
The capillaires enlarging causes the pores to enlarge which allows the white blood cells to change shape and squeeze out of the pores into the tissue fluid. Therefore the tissue fluid has more phagocytes in it this causes the swelling
The excess tissue fluid is drained into the lymphatic system where the lymphocytes are stored this could lead to pathogens to come into contact with lymphocytes and initiating a specific immune response
Explain why smoking leads to increased lung infections
Tar sticked to cilia and cannot waft out the mucus moreover hot smoke burns the throat making it easier for pathogens to get it in
Why do opsins need to be non-specific
They need to bind to all pathogens to bring them closer to the neutrophil and they need to be able to attack to a range of pathogens
What is meant by a non-specific response
A response that is the same for every infection by a pathogen
Describe how a neutrophil performs phagocytosis
As opsin is an antibody it id able to attach to a pathogen as they are non-specific in their shape at the opposite end of the opsonin the antibody can bind to the neutrophil bringing it closer and making it easier to digest
The pathogen is envolped as the phagocyte infolds its memebranes these arms are called pseudopodia and forms a circle around the pathogens called vesticles
A vesticle and pathogen together produces a phagosome
Sacs of lytic enzymes called lysosomes fuse with the phagosome and release enzymes into the phagosome which causes to digested and absorbed into the cytoplasm or ejected from the cell if toxic this destroys the pathogen this is called phagocytosis
Describe how neutrophils are specialised for their roles
They have a multi lobed nucleus this helps squeeze through the pores in the capillary
They are also produced in high numbers in an infection
Why must antigen presenting cells present the antigens of pathogenic organism on a special protein complex
So their not registered as foreign cell and attacked by the lymphocytes this would cause harm to the body
Explain why its important that the antigens on our body cells are not recognised by phagocytes
Otherwise our own body cells will be attacked by white blood cells such as lymphocytes this would still cause the immune system to attack the body
