Cardiovascular System Flashcards
(49 cards)
components of cardiovasuclar system (3)
- blood
- heart
- Blood vessels
what is blood?
a connective tissue made of a plasma liquid matrix containg cells (RBC & WBC) and platelets fibres
Functions of blood (7)
MAINTAIN HOMEOSTASIS!!! via….
- Transport of gases, nurients, + waste products to necessary locations
- Transport processed molecules (e.g. Vit D: skin->liver->kidneys->s.intestine->skeletal muscle)
- Transport regulatory monitors (hormones & enzymes)
- Regulate pH + osmosis
- Maintain body temp (warm blood to surface if too warm so heat can be released)
- protection against forgein substances + organisms (WBC and immune system)
- Clot formation
compoents of blood (2)
- Plasma (fluid, dissolved proteins, metabolites)
2. Formed elements (RBC, WBC, platlets)
Plasma
Collid (liquid containing suspended substances that do not settle out of the solution).
composition: 91% water, 9% proteins, gases, ions, nurients, waste products, hormones & enzymes
function: to transport materials around the body
RBC characteristics
bi-concave discs (providing large SA for dissusion of gases and flexible to fit through BVs), circulate in blood via plasma, ~7-8micro m in diameter
structure of RBCs
no nuclei, few organelles
haemoglobin (pigamented quaternary protein made of 4xhaem groups which have a Fe++ at centre allowing O2 to bind to it during transportation),
lipids, ATP, carbonic anhydrase (enzyme)
function of RBCs (4)
- Carry O2 around the body (O2 binds to iron in haemoglobin- 1O2:1haem group- forming oxyhaemoglobin)
- Carry some CO2 around the blood as a wastre product (binds to AA in globin forming carbaminohaemoglobin)
- Carry nitric acid
- help identification of blood type as they are studded with glycoproteins + glyocolipids
Life Cycle of a RBC (6 stages)
- Erythropoietin produced in kidneys
- transportation of erythropoetin via BS to bone marrow
- In bone marrow Erythropeisis (production of RBCs , taking approx. 4 days)
- RBCs circulate body for approx. 120 days
- in Liver + Spleen memrbane becomes weak due to inability of RBC to produce new proteins causing RBC to repture
- Macrophages release lyosomal enzymes which break down RBCs and release haemoglobin
- –> AA from globin are resued / recycled to make proteins
- –>Haem group: iron is released and carried to bone marrow to produce new RBCs, non-iron converted to Bilirubin for removal of bile in liver
which hormone regulates RBC production?
erythropoetin (increase erythropoetin secretion = increased RBCs produced), secretion stimulated by low O2 levels in blood
what is the other name of RBCs?
Erythrocytes
What is the other name for WBCs and % of blood?
Leukocytes
1% of blood vol.
Function of WBCs (2)
- protect body from invading organisms (e.g. bacteria + viruses)
- remove dead cells and debris from the body
Types of WBC (2)
- Granulocytes
2. Agranulocytes
Granulocytes (feactures, location of production, immune reponse, types (3))
- lob-sided multiple muclei
- cytoplasm contains large granules
Produced: bone marrow
NON-SPECIFIC immune reponse
types: esoinphil, basophil, neutrophil
Agranuloctyes (feactures, location of production, immune reponse, types (2))
-1 large nucleus
- cytoplasm w. small granules
Produced: lymphnodes
ACQUIRED immune response (specific & targeted)
types: lymphcyte, moncyte
Platelets (characteristics-3)
- minute fragments of cells
- contains glycoproteins + proteins on surface allowing connections to other molecules
- short life expecdency (5-9days) so must be continually replaced
Function of Platelets
- First defence for damaged blood vessels -> form ‘platelet plugs’ to seal hole in BVs, promote the formation & contraction of clots in large wounds
What do RBCs contain which allow identification of blood grouping?
Antigens -> glycoproteins + glycolipids
What is the purpose of blood grouping & how does it work?
to protect the body and allow the recognition of ‘non-self cells’. If antibodies in plasma don’t match antigens on RBCs then it will cause an immune reponse to ‘destroy’ forgein cells
Types of antigen grouping (2)
- A, B, O grouping
2. Rhesus system of grouping
A B O grouping
A= A antigen + B antibody B= B antigen + A antibody AB= A+B antigens + no antibodies O= no antigens + A+B antibodies
What happens in A+B antigens-antibodies match?
if the antibody in plasma matches the antigen on RBC
(e.g. A+A or B+B) it will agglutinate (antigen and antibody bind) causing an immune response and rejection of RBCs
Compatibility of ABO transfusions
antibodies->antigens A->A or O-> A B->B or O->B A->AB or B->AB or O->AB or AB->AB O->O
