Blood and blood cells

Question 1

blood composition

Answer 1

plasma 55%
cells and cell fragments 45%

Question 2

plasma composition

Answer 2

water 92%
proteins 7%
other solutes 1.5%

Question 3

plasma proteins

Answer 3

albumins -54%
-osmotic balance
-bind to lipophillic molecules such a fatty acids
-produced by liver
globulins -38%
-alpha and beta transport of chemicals (such as thyroid hormone and iron) clotting factors, produced by liver
- gamma globulins are immunoglobulins
fibrinogen -7%
blood clotting, produced by liver
other proteins -1%
such as lipoproteins

Question 4

other solutes in plasma

Answer 4

• inorganic constituents -1%
• nutrients
• waste products
• dissolved gases
• hormones

Question 5

plasma functions

Answer 5

• regulation of body temp
• regulate water content of cells
• maintaining PH
• proteins in flood aid transport of small molecules such as hydrophillic (vitamin c) and hydrophobic (triglycerides)
• roles in blood clotting (fibrinogen)
• roles in immunology (immunoglobulins)

Question 6

Cells and cell fragments formed elements (45%)

Answer 6

erythrocytes (RBC) 5million
- transport 02 and remove 02 from cells

leucocytes (WBC) 10000
- immunity, allergic reactions

thrombocytes (platelets) 400,000
-blood clotting

Question 7

RBC erythrocytes

Answer 7

• flattened and biconcave
• mature erythrocytes lack a nucleus and mitochondria
• carry o2/co2 associated with haemoglobin
• around 280million haemoglobin in 1 RBC

Question 8

haematocrit

Answer 8

% of total blood volume occupied by RBC
42 percent females
45 percent males

Question 9

haemoglobin

Answer 9

• four pp chains a1 b1 a2 and b2
• can carry 4 02
• can bind 02
• each chain hold a haeme group

Question 10

02/co2 exchange in the body

Answer 10

• oxygen brought into lungs by breathing
  -oxygen moved into lungs and picked up by haemoglobin in rbc
• blood containing oxygen from lungs goes to tissues
• body tissues need oxygen but release carbon dioxide as a waste gas
• when blood reaches tissues
• oxygen leaves rbc and goes in to tissues and haemoglobin picks up co2
• co2 goes to lungs and breathed out

Question 11

red blood cells continuously manufactured in

Answer 11

red marrow of long bones
ribs
skull
vertebrae

Question 12

WBC leucocytes

Answer 12

larger than RBC
have nucleus
lack haemoglobin
immune response
less than 1% of blood volume
5 types
live for a few hours or days but some b and t lymphocytes remain in body for years

Question 13

2 types of WBC

Answer 13

granular
agranular (non-granular)

Question 14

granular

Answer 14

neutrophil
basophil
eosinophil

Question 15

agranular

Answer 15

lymphocyte
monocyte

Question 16

neutrophil functions

Answer 16

• respond first to bacterial invasion
• enter tissue fluid by squeezing through capillary walls
• phagocytic
• release enzymes destroying bacteria
• important in inflammation

Question 17

basophils functions

Answer 17

• similar to mast cells
• synthesis and sores histamine and released during inflammation
• inflammatory response
• liberate heparin seratonin and histamine in allergic reactions

Question 18

eosinophils

Answer 18

• help break down blood clots
• combat effects of histamine in allergic reactions
• fight parasites like worms

Question 19

monocytes

Answer 19

• turn into macrophages
• phagocytosis
• release white blood cell growth factors causing population increase for WBC

Question 20

lymphocytes

Answer 20

• fight infection by providing immune response
• big nucleus
• b cells
• t cells

Question 21

characteristics of WBC

Answer 21

• phagocytic
• chemotaxis ( attracted to certain chemicals released by damaged cells)
• amoeboid movement (cell stretches out, forms temporary projections in order to move) this is in order to squeeze through tissues and reach infections
• diapedesis (leaking through blood vessels to surrounding tissues in response to inflammation or injury)

Question 22

platelets (thrombocytes)

Answer 22

• around 300,000
• no nucleus
• formed from cell fragmentation
• involved with clotting
• contract
• function for 7-10 days before removed by macrophages in liver and spleen

Question 23

haemostasis

Answer 23

• prevention of blood loss from broken vessel
• vascular spasm- vasoconstriction of injured vessel (it narrows) due to contraction of smooth muscle in wall of vessel, spasm will REDUCE blood flow and blood loss not STOP it
• formation of platelet plug- platelets stick to injured area and together
• blood clots

Question 24

blood clotting (coagulation)

Answer 24

• platelet adhesion, platelets stick to damaged blood vessel wall
• platelets release ADP and thromboxane
• these chemicals help attract more platelets to get quicker response
• platelet aggregation, platelets stick together to form platelet plug to temporary seal injury
• coagulation cascade, proteins called clotting factors are released from platelets and damaged tissue and some are already in the liver but circulating in a inactive form
• prothombin turns to thrombin(enzyme) which then turns in to fibronogen then fibrin
• fibrin forms a mesh/ net keeping the platelet plug stable to form a firm clot

Question 25

bleeding disorders

Answer 25

haemophilia- genetic defect, inability to produce certain clotting factors, so clotting cascade doesn’t work thrombocytopenia- low platelet count some people have idiopathic thrombocytopenia and some have as autoimmune disease

Question 26

disorders of fibrinogen

Answer 26

- rare but can be inherited such as: afibrinogenemia- complete lack of fibrinogen hypofibrinogenemia- reduced levels of fibrinogen dysfibrinogenemia- presence of dysfunctions fibrinogen

Question 27

elevated plasma fibrinogen levels

Answer 27

- can be bad as blood may clot too easily even without injury (unwanted clots) - in patients with coronary artery disease diabetes hypertension pregnancy smoking cardiovascular risk factors

Question 28

thrombus

Answer 28

- clot formed in blood vessel where there’s no injury - can happen if blood vessel wall is rough or damaged- like from athersclerosis(build up of fat) - or if blood moves slowly - small bits of fibrinogen builds up and accumulate

Question 29

embolus

Answer 29

- clot that breaks off and moves through blood - can block blood in important places - such as brain leading to stroke - and heart leading to heart attack - and lungs leading to pulmonary embolism

Question 30

clot retraction

Answer 30

- as wound heals plates in the clot contract and tighten - contraction pull edges of wound closer together helping damaged vessel close up and heal quicker fibrinolysis: - protein called plasminogen is in clot as it forms - enzymes such as tpa (tissue plasminogen activator) and urokinase turn plaminogen to plasmin - plasmin breaks fibrin mesh that holds clot together - wbc remove left over bits of broken clot