Lecture 17

Question 1

plasma composition

Answer 1

H2O, ions, organic molecules incl a.a, proteins, glucose, lipids and nitrogenous waste, trace elements and vitamins, gases incl. CO2 and O2. 91% H2O and 8% waste proteins

Question 2

Plasma proteins

Answer 2

important for facilitating function. Albumins are most abundant (60%) where most plasma proteins are synthesised in the liver. Factors are sent into the blood to the liver triggering protein synthesis.

Question 3

Albumin

Answer 3

colloid osmotic pressure

Question 4

globulins

Answer 4

Compose antibodies

Question 5

fibrinogen

Answer 5

clotting factors

Question 6

transferrin

Answer 6

carries iron

Question 7

RBCs

Answer 7

aka erythrocytes, O2 and CO2 transport, no nuclei, biconclave shape increases surface area. Flexible membrane allows RBCs to travel through narrow capillaries without rupturing. Main component is hemoglobin (large complex with 4 globular protein chains 2 alpha, 2 beta) which carries the O2. Each chain wrapped around heme group. The heme group contains Fe and is composed of porphyrin ring that houses a single Fe. A single Fe is capable of conjugating one O2. You can bind 4 O2 per haemoglobin.

Question 8

WBCs

Answer 8

aka leukocytes, five types. Key role in immune response, circulate in blood but act on/in tissues.

Question 9

Platelets

Answer 9

aka thrombocytes. Important in cooagulation, call fragments that split off from Megakaryocytes.

Question 10

Haematopoiesis

Answer 10

starts from single haematopoetic stem cell in embryonic development. Haematopoetic SC differentiates to different lineages. Occurs in bone marrow and once mature BC produced, it is sequestered to circulation. Until 5yrs old, occurs in ALL bones, past that only occurs in select bones (pelvis, spine, ribs, cranium and long bones) at the proximal end. It happens at different rates different rates depending on BC type produced. RBCs take 25% and 75% is dedicated to WBCs at normal physiological conditions therefore, subject to change (depends on factors released and demand) continual process.

Question 11

Haematopoiesis regulation

Answer 11

WBCs: Any permutation of colony-stimulating factors, interleukins and stem cell factor

RBCs: Erythropoietin

Platelets: Thrombopoietin

Question 12

Erythropoiesis

Answer 12

Controlled by glycoprotein erythropoietin (EPO) which is produced in kidneys and some cytokines. Triggered by hypoxia (decreases O2 conc.). When RBC enters circulation, it expels it’s intracellular components in the environment

Question 13

Erythropoiesis steps

Answer 13

1. Stimuli is detected by chemoreceptor
2. Kidneys released EPO
3. EPO travels to bone marrow
4. Haem. P cells differentiate to RBCs (increase RBCs = increases carrying capacity of O2)

Question 14

Blood diagnostics

Answer 14

Complete blood count (CBC) provides info for clinical diagnosis via centrifugal force, blood separated (58% plasma, 42% RBCs, <1% WBCs)

Question 15

Hemocrit

Answer 15

% of total blood count that RBCs make up

Question 16

Buffy coat

Answer 16

Floating laying of WBCs

Question 17

Importance of Iron

Answer 17

70% body’s iron in Hb. Most comes through diet. Fe binds to transferrin and is taken to the bone marrow, it is incorporated into haem groups and then folded around alpha and beta chains to forms haemoglobin and incorporated to RBCs once HPS differentiates. The RBC is recycled in spleen and Hb is split to haem and globin. Haem converts to bilirubin which is excreted in urine, faeces or metabolised to form bile. Excess Fe is stored as ferritin which may be used for RBC production again.

Question 18

Anaemia

Answer 18

Hemocrit ~30%. Blood cannot carry sufficient O2. Dizziness, nausea. Different types/causes

Question 19

sickle cell

Answer 19

abnormal Hb molecules. Genetic defect where glutamate in B chain becomes valine. Results in sickle cell morphology that may cause blockages and rupturing

Question 20

Antibody-antigen interaction

Answer 20

Antibodies are specific to antigens on pathogens. This allows a quick immune response to be mounted. They can group pathogens together to prevent spread and flag them to WBCs.

Question 21

Type A

Answer 21

A antigens therefore, anti B

Question 22

Type B

Answer 22

B antigens therefore, anti A

Question 23

Type AB

Answer 23

Both A and B antigens

Question 24

Type O

Answer 24

No antigen therefore, anti A and B

Question 25

ABO blood groups

Answer 25

Your antibodies are opposite to antigen on RBC as otherwise it would attack your RBCs

Question 26

Compatibility

Answer 26

Very important to match otherwise, donor cells agglutinate together leading them to rupture and increase viscousness of blood risks blood vessel blockage (leads to CV events).

Question 27

donations

Answer 27

blood group O means they won't be attacked therefore, universal donors. Blood group AB means it has no antibodies therefore, universal RBC acceptor

Question 28

Rhesus blood groups

Answer 28

RhD antigen determines if blood type is + or -. If you have the antigen, you don't have the antigen, you have the antibody. Important in preg. as if - mother and + foetus, antibodies in mother attack foetus RBCs leading to haemolytic disease in newborns.