Blood

Question 1

Blood function

Answer 1

move nutrients and waste
regulate pH levels
prevent infections
prevent loss of more blood: coagulation

Question 2

Blood composition

Answer 2

Centrifuge: heavy at the bottom and light on top

Plasma 52%, Buffy coat (platelets and immune cells) <1% and eryhtrocytes/hematocrit 45%

Question 3

Erythrocytes

Answer 3

red blood cells: more in men than women
120 days lifespan

Function:
Carry O2 to tissues. Carry CO2 to lungs
Structure:
biconcave disc: fit through tiny vessel and increase surface area for gaz exchange
no organelles: more room for hemoglobin, proteins and oxygen
carry inside: iron, oxygen, alpha & beta polypeptide cahin => hemoglobin

Question 4

Platelets

Answer 4

fragments of megakaryocytes in bone marrow

function: clump together to seal off damaged vessels
structure: no orgalles

Question 5

Leukocytes

Answer 5

only cell with organelles in blood
function:
ward off pathogens(bacteria and virus), destroy cancer cells, neutralize toxins.
types:
Never Let Monkeys Eat Bananas
-Granulocytes: inflammatory molecules. Most common neutrophils 60% 1st response to infection. Eosinophil parasitic infection. Basophil allergy
- Lymphocytes: B cells, T cells, Natural Killer cells
- Monocytes: phagocyte bacteria

Question 6

Plasma

Answer 6

acellular (no cells)
90% water
10% proteins, electrolytes (Na+, K+, Ca2+, HCO3-, CL-: maintain acid-base, regulate osmolarity) and dissolved gazes
- Albumin (keeps water in blood. transport protein)
-Globulin gamma (antibody that indicate what should be destroyed); alpha;beta
-Fibrinogen clot formation, help platelet plug
Serum = plasma \ fibrinogen

Question 7

Hematopoiesis

Answer 7

renew blood cells
location: bone marrow, only postnatal
prenatal: yolk sac -> liver and spleen -> bone marrow
hemopoietic stem cell is pluripotent and give rise to all blood cell. It differentiate into progenitor cells of different types: lymphoid, myeloid -> megakaryocyte, granulocyte/monocyte

Erythropoeiesis is the production of rbc in particular

Question 8

Erythropoeiesis

Answer 8

2 million rbc produced / sec
2.5 billion / day

hemocytoblast (multipotent) -> pronormoblast/proerythroblast -> early normoblast/erythoblast -> intermediate normoblast -> late normoblast -> nucleus expelled and become reticulocyte (1-2% ind blood) -> erythrocyte

important factors: iron, vitamin folate and B12, glucose, lipids and amino acids

Question 9

Iron

Answer 9

better absorbed from meat than plants
stored in bone marrow, liver and spleen
Erythropoietin (EPO) up -> iron released -> bound to transferrin -> carried to red marrow -> attaches to erythrocyte
1 iron in heme -> 1 binding site for O2 => without it can’t have proper hemeglobin

Question 10

Vitamins

Answer 10

B12 & folate

Help DNA synthesis

Question 11

Red blood cell regulation

Answer 11

Erythropoietin (EPO): glycoprotein cytakine secreted by kidneys. It is a long term effect of altitude. It makes iron release and increase eyrthropoiesis.

O2 down -> detected by renal interestitial peritubular cells -> erythropoietin in kidneys up -> erythroupoiesis up -> rbc up and thus hb up -> O2 up -> EPO down

Question 12

Red blood cells degradation

Answer 12

spectrin and aigorin gets degraded
spleen: rbc trapped there
120 days -> degradation -> removed by macrophage
globin (part of hemoglobin) -> broken into amno acids -> bone marrow -> new erythrocytes
hemoglobin -> broken down -> alpha and beta polypeptide chains -> removed by kydneys
Iron (in heme of hemoglobin) -> stored in liver -> ferritin to bone marrow -> new erythrocytes
Rest of heme -> (biliverdin and) bilirubin -> bind to albumin -> liver -> bile OR -> intestines -> feces OR kidneys -> urine

Question 13

Red blood cells metabolism

Answer 13

Limited metabolic activity
Don’t use a lot of energy
Energy source: glucose -> cannot do aerobic glycolysis -> x krebs cycle

Question 14

Anaemia

Answer 14

RBC down or Hb down or ability to carry oxygen down or Iron down

Question 15

Hemolysis

Answer 15

rupturing of red blood cells, release content into surrounding fluid. Can lead to anemia
intensive exercise
metabolic

Question 16

Iron metabolism

Answer 16

Most contained in RBC
cellular respiration: allow ATP synthase
Oxygen transport: heme group
toxicity

Fe3+ -> duodenal cytochrome B (on enterocyte lumen) -> Fe2+-> divalent metal transporter 1 (on enterocyte lumen) -> Fe2+ uptake by enterocyte -> bind to ferritin OR -> go through ferroportin 1 -> blood vessel -> bind to transferrin (from bone) -> Fe2+ to liver -> Fe2+ goes up -> liver release hepcidin in blood -> ferroportin 1 is inhibited -> Fe2+ is stuck and secreted in feces

Question 17

Vitamin C

Answer 17

increase the absorption of non heme iron

facilitate iron absorption from GI tract