Advertisement Upgrade to remove ads

BMS130

What are the functions of the circulatory system

Transport:
•oxygen
•wastes
•nutrients
•hormones

Protection:
•antibodies
•white blood cells
•platelets

Regulation:
•fluid volume
•ph
•temperature

Name and describe the components of blood

adults-4/6 litres

•Erythrocytes
•Platelets
•Leukocytes
•Agranulocytes


PLASMA
-90% water
-8% proteins / albumins/globulins/fibrinogens
-2% other / amino acids/wastes/nutrients/O2/CO2/electrolytes

FORMED ELEMENTS

Explain the importance of blood viscosity and blood osmolarity

Increased RBC count = increased viscosity = increased blood volume/pressure

High osmolarity = high fluid absorption

low osmolarity = fluid remains in tissues

Describe the structure and function of erythrocytes and their relationship to haemoglobin

lack nucleus, organelles (mitochondria), contains cytoskeletons.
Basically bags of haemoglobin 280 million
7.5 micrometers

Describe the life cycle of erythrocytes

120 day life span

Erythrocytes produced in the red bone marrow, erythropoiesis (takes 3.5 days)

Pluripotent stem cell
|
colony forming unit
|
erythroblast - nucleus becomes reticulocyte
|
erythrocyte

RBC lyse in spleen
|
macrophages destroy destroy RBC
|
Haem + Globin are split
|
iron is salvaged and hydrolysed into amino acids

Haem turns to biliverdan and iron
•biliverdan becomes biliruben

What is anaemia, it causes and consequences of this condition

Anaemia - blood is abnormally carrying low oxygen
•decreased RBC count
•low haemoglobin content (vitamin b12 deficiency)
•hereditary defects (sickle cell anaemia)
Hypoxia results with no oxygen, oedemas form due to reduced osmolarity, cardiac failure as viscosity drops.

What determines a persons ABO and RH blood type and how does this relate to transfusion compatibility

Blood type are determined by the presence of glycoproteins called antigens on the RBC

these help to determine which matter is its own

RBC's can have:
•A antigens
•B antigens
•AB antigens
•O antigens

the RH is the presence of the D antigen, positive if present.

The presence of antibodies and antigens is related to the transfusion compatibility

What is haemolytic disease of the newborn and why does it occur?

Occurs with the second newborn (RH+)
mothers (RH-) anti D antibodies cross placenta

prevented with Rohlum

Detail relative abundance of each of the five leucocytes

Neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophils

Describe the structural characteristics of each of the five leukocytes and their functions

Neutrophils
•fine granules in cytoplasm
•3-5 lobed nucleus
•phagocytosis of bacteria
•release antimicrobial chemicals

Lymphocytes
•variable amounts of blueish cytoplasm
•destroy cells
•present antigens to activate other immune cells
•secrete antibodies and provide immune memory

Monocytes
•largest type
•kidney shape nucleus
•differentiate into macrophages
•phagocytosize pathogens and debris
•present antigens to active other immune cells

Eosinophils
•nucleus has two large lobes
•phagocytosize of antigen antibody complexes, allergens and inflammatory chemicals
•release enzymes to destroy parasites

Basophils
•large, abundant, violet granules
•s shaped nucleus
•secrete histamine
•secrete heparin

Describe the life cycle of leukocytes

Leukopoises
pluripotent cell
•myoblasts - form nuetrophils, eosinophils, basophils
•monoblasts - form monocytes
•lymphocytes - form form BT lymphocytes and natural killer cells

red bone marrow stores and release granulocyte and monocytes

circulatory WBC do not stay in bloodstream
-granulocytes leave 8 hours, live 5 days longer
-monocytes leave 20 hours, live several years
-WBC long term - decades

What are platelets and what are their functions

•Call fragments of megakaryotes
•essential to clotting
•involved in all 3 mechanisms of hemostasis
•live for 10 days
•secrete vasoconstrictors
•seal small seal breaks
•secrete clotting factors/growth factors
•initiate clot dissolving enzyme
•phagocytocize bacteria
•secrete neutrophil and monocyte attractors to inflammation site

Explain the first three mechanisms of hemostasis

•Vasoconstriction (vascular spasm)
injury to smooth muscle
seratonin
reflexes

•Platelet plug formation
platelets adhere to exposed collagen fibres of endotehlium
psuedopods stick
platelets degranulate secreting dialators
positive feedback until vessel sealed

•coagulation
clotting plasma protein fibrinogen converts to insoluble threads, procoagulation, activation of cascade
extrinsic initiated by damaged walls
intrinsic initiated within blood

What keeps blood clotting in the absence of injury?

Platelets do not stick to prostacyclin coating

thrombin dilution

Natural anticoagulants: heparin/anti thrombin

What are some consequences of unwanted blood clotting

•embolism
•thrombosis
•infarction

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set