68. blood plasma, antibodies Flashcards
what is blood plasma and how much of the blood does it take up
Contains substances that take up 7% of its weight ( mostly plasma proteins).
90% of plasma = water.
Makes up 55% of the blood
what substances take up that 7% in weight in plasma?
. plama proteins
. nutrients
. respiratory gases
. nitrogenous waste products
. hormones
. electrolytes
what are the major plasma proteins in blood and there function
. Albumin - Forms majority. made in liver + maintains osmotic pressure in blood. contributes blood viscosity
. Globulins (alp + Bet) - made in liver. includes transfer factors: transferrin, fibronectin, prothrombin. lipoproteins and other proteins entering blood from tissues. alp transports lipids, beta transports Fe ions and lipids in bloodstream.
. Immunoglobins (antibodies/y globin) - secreted by plasma cells
. Fibrinogen - made in liver. largest plasma protein. DOes blood clotting. During clotting, it polymerizes as insoluble, cross-linked fibres of fibrin that block blood loss from small vessels.
. Complement proteins - comprise a defensive system important in inflammation and destruction of microorganisms
What do plasma protein do
Buffer against ph changes
what are antibodies
Antibody = Y shaped glycoprotein that interacts with an antigen. used to identify and neutralize pathogens.
Each contains a paratope that is specific to specific epitope on an antigen allowing precision binding.
can exist as a soluble form in blood plasma /
as a membrane bound form attached to the surface of B cells.
main function of antibodies
. Agglutination - antibodies stick to antigens and allow phagocytosis
. Neutralisation - antigen has parts of its surface blocked to make its attack ineffective
. Precipitation - antibodies glue together soluble antigens forcing them to precipitate out solutions, making them targets for phagocytosis.
. Complement activation - antibodies encourage antigen to unravel.
