Anaemia

Front 1

What is the structure of an Erythrocyte and how does this relate to its function? What is its lifespan? What enzymes does it contain? Where is it removed?

Back 1

Structure:
Biconcave Disk (7micrometres)
Because of lack of nucleus. Increases SA/V so 02 and CO2 can diffuse quickly.



Plasma Membrane (glycoproteins and glycolipids- determines blood type)


Inner surface is actin, increases membrane resiliance and durability. RBC's can stretch/bend/fold (can be 3micrometres)


Cytoplasm is 33% Haemoglobin.

Function: Pick up Oxygen, deliver it to tissues. Pick up Carbon Dioxide from tissues, deliver it to the lungs.

Short lifespan (120 days) because of no DNA/RNA (ie no ability to synth. proteins)

2 Enzymes:
Glycolytic enzymes:
Without mitochondria (ie no oxidative phosphorylation) they cannot use 02 they contain so must rely on glycolyses for ATP needed for active transport mechanism to maintain intracellular ionic conc.)

Carbonic Anhydras:
catalyse key reaction for CO2 into HCO3-, this is the main form in which CO2 is transported in blood


Removed in circulation by the spleen (narrow vasoculture breaks the fragile old ones)

Front 2

What are the two Different Types of Leukocyte? Describe the main differences.

Back 2

Granulocyte:
Ie can secrete Granules
Has a nucleus with several lobes.

Agranulocyte:
Is mononuclear
No granules to secrete.

Front 3

Describe the characteristics of Neutrophils. What is their lifespan, size and function?

Back 3

Are Granuloctes.
Most abundant type of WBC: 60%
Lifespan is 7 Hours.
Size is 9-12micro meters.
Function is to phagocytose, squeezing through capillary walls. bacteria and debris.
Are multilayered.

Front 4

Describe the characteristics of eosinophils, what is their lifespan, size and function?

Back 4

12 micro metres
Granulocyte
8-12days
3% of all leukocyte
Attack parasitic worms, inflammatory cell in allergic reactions.

Front 5

Describe the Characteristics of Basophils: what is their size, lifespan and function?

Back 5

9 micro metres. Few hours to a few days. 0.5% all leukocytes. Release histamine and heparin. Histamin is important in allergic reactions, heparin clears fat from blood.

Front 6

Describe the characteristics of monocytes: what is their size, lifespan and function?

Back 6

13micro metres. 3 days. 4% leukocytes. In TRANSIT to become MACROPHAGES.

Front 7

Describe the two types of lymphocyte. Their function?

Back 7

B Lymphocyte: Secrete antibodies
T Lymphocytes: Cell-mediated immune response. Inflammatory T-Cells recruit macrophages + neutrophils to the site of infection. And kill virus infected cells. Helpter T Cells secrete Cyotkines. NK cells lyse virus-infected cells.

Front 8

Describe the Characteristics of platelets

Back 8

3micrometres. 10 days. 250 milllion per litres of blood.

Front 9

Key Facts about Blood:
What vol?
What % weight?
Why do we need
What are the 3 main roles?

Back 9

5l women, 5.5l men.
8% body weight.
diffusion to slow to accommodate us.
3 main roles:
Transport (gases, hormones, nutrients, wastes)
Regulation (homeostasis: pH, water, electrolytes, temp)
Defence (carries Immune Cells)

Front 10

Describe the Composition of blood:

Back 10

Plasma is 55%:
90% of that is water (medium, good heat capacity.
7% is protein (50% of that is albumins, 7% is fibrinogens, 40% is globulins, 1% is other)
1.5% is dissolves solutes

45% is formed elements or haematocrit:
99% of that is erythrocytes
Leukocytes
Platelets

Front 11

Describe the functions of Plasma's constituents.

Back 11

Water (90%):
Transport
Heat: carrying/absorbing

Electrolytes (1%)
Mostly Na,Cl,HC03,K,CA:
Membrane excitability, osmotic distribution of fluid between ECF + ICF
Buffer pH changes

Nutrients, wastes, gases, hormones. Glucose, amino acids, lipids, vitamins; creatine, bilirubin, urea:
Tranposrted... CO makes changes of pH

Proteins: 8% mostly made by liver
Albumins: Transport many substances (ie bilirubin, bile salts, penicillin)

Globulin:
Alpha/Beta: transport many water-insoluble substances (thyroidhormone, cholesterol) + Clotting factors (fibrinogen) + inactive precursor molecules AGII)

Gamma globulins (made by lymphocytes, not liver)
antibodies/immunoglobulins.

Front 12

Describe the two parts of Haemoglobin and what it can bind with.

Back 12

Two parts:
Globin (protein made up of four highly folded polypeptide chains (2alpha, 2beta)
Haem groups:
nonprotein groups with iron, each bound to one polypeptide. Iron can combine reversibly with one molecule of 02. 98.5% of O2 in the blood is bound to haemoglobin.


It can combined with:
02/c02/
H of h2c02 (generated at tissue, haemoglobin buffers this, so no pH change of blood)
CO
NO (binds in the lungs, released at the tissues where it relaxes and dilates local arterioles)

Front 13

Define:
Haemotopoiesis
Erythropoiesis

Give an overview of bone marrow

Back 13

Haematopoiesis:
The production of blood cells.

Erythropoiesis:
The production of erythrocytes.

Bone Marrow:
soft, highly cellular tissue that fills internal cavities of bones.
Red Bone marrow: capable of erythropoiesis. all marrow is red while young, grows yellow as grow old. remains in isolated places such as the sternum and ribs.


Yellow Bone Marrow: fatty, Incapable of erythropoiesis. severe blood loss for trauma means increased demand for haemopoiesis, yello marrow has ability to revert back to red marrow.

Front 14

Give an overview of haematoposiesis:

Back 14

RBmarrow contians UNDIFFERENTIATED pluripotent stem cell (gives rise to every type of blood cell).

if mature into RBC, released into capillaries via SINUSOIDS that permeate marrow, regulatory factors act on what type.

myeloid stem cells are everything that isn't lymphoid stem cell.

Front 15

Erythropoiesis process:

Back 15

Myeloid stem cells go to
Proerythroblast: large cell which contains a LARGE LIGHTLY STAINED nucleus. proliferate, decrease in size + conc. of chromatin
basophilic erythroblast: changes in staining characteristic of their cytoplasm.
PLUS HAEMOGLOBIN
polychromatophilic erythroblast
then
orthochromic erythroblast (normoblast) (NOW IN BLOOD)
then extrude nucleus + organelles for more room for Hb
RETICULOCYTES: stay in bone marrow or spleen for a few days to mature to RBC
ERYTHROCYTES

Front 16

Requirements for the formation of RBCs

Back 16

Fe2+ and amino acids are needed for HB.

Folate + VB12 are needed for maintaining fast rate of cell division

Vitamin C and Cu (copper) are co-factors for several steps in the synthesis of Hb

Front 17

Describe where + when erythropoiesis occurs:

Back 17

Intrauterine: yolk sac then developing spleen, liver, lymph nodes (till bone marrow formed + takes over)

Children (most bones)

Adult (red marrow bones): sternum, ribs, vertebrae, ilia, humeria and tibiae (proximal parts)

Front 18

Describe the control of RBC production by Erythropoietin:

Back 18

KIDNEYS (JGA) see low 02 delivery - more ERYTHROPOIETIN - more proliferation + maturation of undifferentiated stem cells into RBCs - more RBC.

severe blood loss. 6 times as much hormone in the blood.

Front 19

Key facts about iron:
how much in blood (m/f)?
How much lost and in what way?
how much do we ingest?

Back 19

3.8g male, 2.3g female.
lose 1mg day GI epithelial shedding
greater than 2mg per day female menstruation

lose 0.5-1ml blood in faeces per day.

ingest 10-15mg a day. 10% has bioavailability (1-1.5mg/day)

need a lot of iron to actually impact iron pool.

Front 20

Describe the production of haemoglobin:

Back 20

Heme synthesised in mitochondria + cytosol of immature RBC
Globin protein: ribosomes in the cytosol.
HB continues to reticulocyte from proerythroblast.
then nucleus lost means no more production.... except for rRNA until reticulocyte loses RNA after entering vasculature.

Front 21

Describe Iron absorption:

Back 21

2 steps:
into lumen
epithelial of lumen into blood

heme iron (iron bound to heme) absorbed efficiently.
inorganic iron in meat (mostly oxidised ferric fe3, but sometimes fe2 (which is easier))

fe3 to fe2 via membrane-bound enzyme before absorption
vitaminc increases iron absorption
phosphate + oxalate combine with ingested iron to form insoluble iron salts.

fe is bound to gastroferritin until SI.

heme iron enters via HEME CARRIED PROTEIN 1. then degraded via haem oxygenase into amino acids and iron.

fe2 enters via DIVALENT METAL TRANSPORT 1 (also carries other irons with 2+)

Front 22

Transport of absorbed iron?

Back 22

Needed immediately is taken to bone marrow.
iron absorption is controlled by HEPCIDIN
too much iron means hepcidin binds with ferroportin- promoting its internalisation into the cell by endocytosis + degradation by lysosomes

transferrin carries iron that has exitted epithelial intestine cell

Front 23

Excretion of iron?

Back 23

Iron that is not immediately needed is irreversibly stored in granular FERRITIN within ENTEROCYTES, cannot be absorbed

ferritin lost in feces within 3 days. epithelial cells sloughed off at this rate

Front 24

Describe the Deep iron stores

Back 24

Ferritin: stored in liver, spleen skeletal muscle, enterocyte + bone marrow.

Haemosiderin in pathological state (systemic)

Hepatocytes in the liver:

Transferrin around the body (increased levels when more iron required ie FeD anaemia)

replenishment is around 6 weeks.

Front 25

How does Hepcidin control iron intake

Back 25

liver receives blood via portal vein (from spleen and intestines).
iron enters as diferric transferrin.
hepatocytes have recep's for it.
releases hepicidin. hepcidin binds to ferroportin, stimulates ferroportin endocytosis and degradation. therefore nothing can take iron so its not absorbed.

Front 26

Define Anaemia.
What are the 3 main categories of Anaemia, by cause?
What are the 3 Main categories of Anaemia, by MCV?

Back 26

Anaemia:
HB<125g/L in adults or 110g/L in children.
Decrease of O2 Carrying capacity of blood even though normal PO2

3 Main categories (by cause):
Inadaquete Erythropoiesis
Haemorrhoage
Haemolysis

3 Main Categories (by MCV):
MCV=Mean Cell Volume.
RBC with low MCV are small (microcytic) + pale (hypochromic)
Macrocytic (high MCV, are also round or oval shaped)
Normocytic/Normochromic (RBC are normal in shape and size, but reduced in number).

Front 27

Causes of Inadequate Erythropoiesis?

Back 27

PRAN
Pernicious Anaemia
Aplastic (hypoplastic) Anaemia
Renal Insufficiency
Nutritional (iron/folate/b12/C)

Front 28

Causes of Haemorrhagic Anaemia?

Back 28

RUM THE

Ruptured Aneurysm
Ulcer
Menstruation
Trauma
Haemophilia

Front 29

Causes of Haemolytic Anaemia?

Back 29

Drug Reactions
Poisoning
Parasitic Infections
Hereditary Disease (Thalassaemia/Sickle cell)
Blood type incompatibilities
Anaemia of Chronic Inflammatory Disease

Front 30

Causes of Microcytic Anaemia

Back 30

Lack of haemoglobin causes it.
Thalassaemia Minor
Chronic Disease
Fe deficiency
Chronic blood loss (parasites/cumulative menstral/GIT bleeding)
Diet
Decreased Absorption
Increased demand
Vitamin C def.
preggies

Front 31

Causes of Normocytic Anaemia

Back 31

Acute blood loss (immature RBC)
Chronic Disesase
Hypothyroidism

Front 32

Causes of Macrocytic Anaemia

Back 32

Larger RBC (lack of division)
B12/folic acid deficiency
(Decreased Rate of erythropoies
decreased RBC count
fragile/enlarged rbc destroyed under pressure
excessive lysing (swollen spleen/jaundice)