Blood

Question 1

general composition of blood:

Answer 1

plasma + formed elements: - - erythrocytes (RBC), leukocytes (WBC), platelets

Question 2

clotting occurs by:

Answer 2

formed elements and serum (plasma without

Question 3

type/ function of blood:

Answer 3

specialised ct.

• for transport (of nutrients, remove end products, hormones)
• regulation (homeostasis)
• protection

Question 4

blood composition of centrifuged blood and %:

Answer 4

hematocrit (RBC at bottom)

• 35-45% women
• 40-50% men

buffy coat (WBC middle)

plasma at top

Question 5

plasma function:

Answer 5

maintains osmotic pressure, transport, clotting, immune function

Question 6

plasma features:

Answer 6

aqueous solution (90% water)

solutes:
- proteins (7-8%): albumin, globulins (incl. immunoglobulins), (help clot) prothrombin + fibrinogen

• electrolytes
• nutrients, blood gases, hormones, waste products

Question 7

where are blood cell types originated?

Answer 7

all blood cell types: bone marrow ct.

• erthrocyte (RBC) only in blood
• leukocyte (WBC) in other ct. and blood

Question 8

function of erythrocytes and brief info:

Answer 8

RBC: oxygen and co2 transport

heamoglobin (protein + iron) carries oxygen

Question 9

shape of erythrocytes:

Answer 9

biconcave disc, to increase SA:V ration

mature cells: no nucleus or organelles

Question 10

lifespan of erythrocytes and removed by:

Answer 10

in adults: approx 120 days

removed by spleen, bone marrow and liver

Question 11

Anemia eg:

Answer 11

abnormally low heamoglobin conc. and/or RBC count

• iron deficiency
• pernicious (insuffcient B12- helps mature RBC/ change shape)
• aplastic
• sickle cell

Question 12

how is blood groups classified:

Answer 12

from antigens on RBC

14: A/B/O/AB and +/-

Question 13

function and shape of leukocytes:

Answer 13

defense,

spherical shape (in plasma) but some: ameboid/motile leaving blood vessels to invade tissues

Question 14

2 classifications of cell type leukocytes: and how

Answer 14

type of granules and nuclei shape

• granulocytes (polymorphonuclear: PMNs)
• agranulocytes (mononuclear)

Question 15

features: granulocytes

Answer 15

nuclei have 2+ lobes, specific granules (bind neutral/basic/acidic component of dye mixtures) special functions, azurophilic granules (stain purple)

Question 16

features: agranulocytes

Answer 16

round of indented nuclei, only has azurophilic granules

Question 17

types of granulocytes:

Answer 17

neutrophils, eosinophils, basophils

Question 18

types of agranulocytes:

Answer 18

lymphocytes, monocytes

Question 19

neutrophils: function/ shape/ %

Answer 19

most common (50-70%)

• multi lobed nucleus (3-4)
• phagocytic (lysosomes), central in response: infection, injury, inflammation

Question 20

eosinophils: function/ shape/ %

Answer 20

1-5% leukocytes

• bi lobed nucleus
• large ovoid granules
• similar size to neutrophils
• proliferate in allergic reactions, parasite destruction, phagocytosis

Question 21

basophils: function/ shape/ %

Answer 21

rare: < 1%
- similar size to neutrophils
- nucleus in irregular lobes (obscured by specific granules)
- allergy, inflammation, granules have heparin (anticoagulant), histamine (cause hypersensitive reactions: hay fever, asthma)

Question 22

monocytes: function/ shape/ %

Answer 22

2-8%

• largest of leukocytes
• nuclei indented (kidney bean/ horseshoe)
• pale cytoplasm
• phagocytic (engulf foreign microorganisms, dead/worn out cells, other tissue debris)
• close interactions with lymphocytes to recognise/ destroy foreign substances

Question 23

lymphocytes: function/ shape/ %

Answer 23

20-40%

• small/ med/ large
• deeply staining nucleus, relatively thin rim of cytoplasm, no specific granules
• recognise/ respond to antigens, for cell mediated immunity: viral infections
• T, B, NK cells
• can’t histologically distinguish T and B cells

Question 24

basophils: found where/ lifecycle

Answer 24

found in tissues with allergic reactions

1-2 years approx

Question 25

lymphocytes: found where/ lifecycle

Answer 25

leave capillaries/ venules-> ct. will differentiate into macrophages

days in blood
months in ct.

Question 26

monocytes: found where/ lifecycle

Answer 26

seen in ct. and epithelium
- densely packed in lymphoid tissue (spleen, lymph nodes, tonsils)

months - years

Question 27

lymphocytes: found where/ lifecycle

Answer 27

seen in ct. and epithelium
- densely packed in lymphoid tissue (spleen, lymph nodes, tonsils)

months - years

Question 28

monocytes: found where/ lifecycle

Answer 28

leave capillaries/ venules-> ct. will differentiate into macrophages

days in blood
months in ct.

Question 29

difference btw eosinophils/ basophils:

Answer 29

more likely eosinophil than basophil
- eosinophil: 2 lobes equal size, dense granules in cytoplasm

• basophil: 2-3 lobes less defined, less granules- not dense mass

Question 30

larger than usual no. of neutrophils may indicate:

Answer 30

acute or chronic infection

Question 31

? increases due to allergic disorders:

Answer 31

basophils and eosinophils

Question 32

leukaemia may have:

Answer 32

large no. of immature leukocytes

Question 33

thrombocytes: features and ?/ml

Answer 33

• fragments of cells
• no nuclei but have mitochondria, ribosomes, enzyme systems and 4 types of granules
• 250 000 - 500 000/ ml

Question 34

thrombocytes: function and life span

Answer 34

• promote coagulation
• repair gaps in blood vessel walls: aggregation, adhesion to self and endothelium,
• also activate clotting factors in plasma: fibrin, release serotonin (for vasorestriction)

10 days

Question 35

what blood cells formed in: myeloid tissue

Answer 35

red bone marrow:

• erythrocytes
• granular leukocytes (neutro/basal/eosinophils)
• thrombocytes (platelets)

Question 36

what blood cells formed in: lymphoid tissue

Answer 36

lymph nodes, spleen, thymus:

- agranular leukocytes (mono/lymphocytes)

Question 37

what blood cells formed in: during embryonic and foetal development

Answer 37

yolk sac, liver, spleen

Question 38

? stem cells give rise to all cell types:

Answer 38

pluripotent stem cells

- under control of cytokines and growth factors