Body Fluids Mcqs 3s6m4n

Body Fluids MCQs These questions incorporate elements from the section on the level of water in the body and its distribution covered at the beginning of FM1001 and from the blood section of FM1002, with some clinical questions included when relevant.

1.Extracellular Fluid differs from intracellular fluid in that: It has a greater volume It has a lower tonicity Its anions are mainly inorganic It has a higher sodium:potassium molar ratio Its pH is lower 2.Blood group antigens (agglutiogens) are: Attached to the haemoglobin molecule Simple proteins All of similar immunogenicity Inherited characteristics carried by the X chromosome Inherited as recessive characteristics 3.Total body water: Forms a smaller percentage of body weight in fat persons than in thin Can be measured by an indicator dilution technique using deuterium oxide as the indicator Comprises half to two thirds of body weight in young adults Is a smaller proportion of body weight in men than in women Falls during starvation as a percentage of body weight 4.The breakdown of erythrocytes in the body yields: Iron, most of which is excreted in the urine The pigment bilirubin which is water soluble The pigment bilirubin which is conjugated in the liver Amino acids which are available for general use Bile Salts such as sodium taurocholate 5.A person with group B blood:

Has ant-B antibody in the plasma May have the genotype AB May have a parent with group O blood May have children with only B or O group blood Whose partner is also B must have children of group B or O

6.Blood platelets are important in stopping bleeding in that: They release chemicals which have a role in the clotting process They become sticky and adhere on exposure to collagen They are an important source of calcium for the clotting process The bleeding time is increased when the platelet count is low They break down to release a vasoconstrictor substance at the site of haemorrhage 7.Bilirubin Is a steroid pigment Travels from red cell breakdown sites to the liver in the plasma Contains iron Is present in bile in a conjugated state Promotes the normal digestion and absorption of fat 8. Monocytes Originate from precursor cells in lymph nodes Are phagocytic Migrate from the blood into the tissues Can transform into tissue macrophages Manufacture immunoglobin M 9.Erythrocytes Are responsible for the major part of blood viscosity Contain the enzyme carbonic anhydrase Increase their volume in hypertonic saline Burst when mixed with 0.9% (150mmol/litre) saline Do not require energy for metabolic activities 10. Neutrophil granulocytes Are the commonest leucocytes in normal blood Contain lysosomes with digestive enzymes

Are confined to the circulation Contain actin and myosin filaments Are present in high concentrations in pus

11.Bleeding from a small cut in the skin Is normally diminished by local vascular spasm Ceases within about five minutes in normal people Will be prolonged if there is a severe deficiency of factor VIII Is greater from warm skin than from cold skin Is greater from a dependent than from an elevated arm 12. Circulating Red Blood Cells Include about 1% which retain their nuclei May show a network pattern when appropriately stained Are distributed evenly in the blood stream Travel more slowly through venules than capillaries Are deformed as they through the capillaries 13.Lymphocytes Constitute 1-2% of circulating white cells Are motile Can transform into plasma cells Decrease markedly in number with removal of the adult thymus Are decreased in number by immunosuppressive drugs 14. Blood Comprises about 7% of body weight Comprises a higher percentage of body weight in fat people than in thin people Volume can be calculated by multiplying plasma volume by haemoglobin concentration Volume rises when water is drunk Which has clotted releases serum 15.Human Cell Membranes Are impermeable to fat soluble substances Are more permeable to sodium than to potassium

In skeletal muscle have their permeability to glucose altered in the presence of insulin In skeletal muscle have their permeability to potassium decreased in the presence of insulin Contain lipid and proteins only

16. Lymph Contains plasma proteins Vessels are important in the absorption of protein from the intestine Production in muscle increases during muscular activity Is cell free Flow depends critically on the contraction of adjacent skeletal muscles 17.Blood platelets Are formed in the bone marrow Increase in number after injury and surgery Have a small single lobed nucleus Alter shape when in with collagen Are normally more numerous than white blood cells 18.An appropriate dilution indicator for measuring Total body water would be sucrose Plasma volume would be radioactive sodium Extracellular volume would be insulin Intracellular volume would be heavy water (deuterium oxide) Total body potassium would be radioactive potassium 19.Transfusion of blood Of group A to a group B person causes a severe reaction Of group O to a group AB person causes a severe reaction Of group A to a group O person causes a severe reaction Of group A to a group AB person causes a severe reaction Which is rhesus negative to a rhesus positive person causes a severe reaction 20. Rhesus disease of the newborn Is due to breakdown of the infant’s red cells Causes a yellow appearance (jaundice) in the infant

Occurs in infants of a rhesus positive mother Occurs in rhesus negative infants Can be prevented by giving D antigen to appropriate women immediately after delivery of abortion

21. The rate of red cell formation is increased By Vitamin B12 injections to healthy people on a normal diet A week after a blood donation In someone suffering from anaemia due to excess haemolysis By erythropoietin in someone without kidneys When the blood reticulocyte count is raised 22. Vitamin B12 deficiency Leads to anaemia with small pale red cells May result from wasting (atrophy) of the gastric mucosa May result from disease of the terminal part of the ileum May lead to a reduction in the circulating platelet level May lead to impaired function in the nervous system 23. A raised level of calcium in the blood (hypercalcaemia) Causes increased excitability of nerve and muscle Is caused by chronic renal failure Increases the risk of stone formation in the urinary tract Is a consequence of decreased parathyroid activity Is a consequence of a reduction in the plasma protein level

ANSWERS F- Cells contain half to two thirds of body water therefore ICF > ECF F- If this were true, water would be drawn by osmosis into the cells. In reality the intracellular substances produce enough osmotic pressure to balance the Hb, potassium ions etc of the ECF and thus the two are equal T- Organic anions are products of metabolism, produced inside the cell (proteins and organic phosphates), outside the cell it is mostly Chloride and Bicarbonate T- The concentration of [Na ions] in the ECF is 142mEq/l and [K ions] is 4mEq/l giving a ratio of over 30 to 1. The ICF ratio is 1:14 in the other direction F- Intracellular pH is lower due to metabolism F- They are part of the red cell membrane (the Hb molecule is located inside this again) F- They are glycoproteins F- A,B and D are more immunogenic than the others F- They are carried by autosomes (Chromosomes are all autosomes except for the sex determining pair referred to as the X or Y chromosome) F-They are mendelian dominant T- Fat contains relatively little water compared with other tissues T- Deuterium oxide (aka heavy water) can be used T- A percentage which falls with age F- Women have more fat and thus less water on average than men F- It rises as the fat stores are metabolized F- Most iron is retained for further use F-It is bound to circulating plasma proteins T-It is conjugated to form bilirubin glucuronide which is water soluble and excreted in the urine T- The AAs come from the globin part of the Hb molecule F-Bile Salts are formed in the liver F- Antibody B in the plasma would then cause agglutination (agglutinins attach to the walls of the red cells and cause masses of RBCs to accumulate)

F- This would give blood group AB T- Then they would have inherited the O from one parent and B from the other to give the genotype BO which is the same as B F- A or AB are possible depending on the partner’s genes T- There is no group A gene in either parent T- including Thromboplastin T- Forming Platelet Plugs F- Calcium is found abundantly in plasma T- As platelet plugging is impaired T- This is known as Serotonin F- It is a porphyrin pigment derived from Haem T- The water insoluble bilirubin forms a water soluble complex with plasma protein F- Iron is removed from haem in the formation of bilirubin T- It is conjugated with glucuronide F- Bile salts not bile pigments are needed for this F- They originate from precursor cells in bone marrow T- They ingest dead granulocytes T- Here they ingest dead granulocytes T- These are important scavenger cells F-Immunoglobins made by lymphocytes T- Blood viscosity rises exponentially with the haematocrit T- This catalyzes the formation of bicarbonate from water and carbon dioxide F- Osmosis causes water to leave the cells and they shrink F- This is isotonic with their contents F- They use energy generated from glycolysis to maintain electrochemical gradients across their membranes T-They comprise 60-70% of circulating leucocytes T- The granules contain enzymes which digest the bacteria F- They leave capillaries by the process of diapedesis T- This may be related to their motility T- Pus consists largely of dead neutrophils

T-Vascular smooth muscle contracts in response to local damage and release of serotonin from adherent platelets T- This is the upper limit of the normal ‘bleeding time’ F- Bleeding time is independent of clotting time (which would be prolonged in this case) T- Warmth dilates blood vessels in the skin T- Due to the greater intravascular pressure in the dependent limb F- Nucleated red cells are not normally seen in the blood T- Reticulocytes are the most immature circulating form F- They form an axial stream away from the vessel wall F- Capillaries have a greater total cross-sectional area T- Normal cells are around 7 microns in diameter become bullet shaped as they through 5 micron diameter vessels F- They constitute 20-40% T- They move to areas of chronic inflammation T- It is in this form that they produce antibodies F- The thymus has little function in the adult T- Lymphocytes and immune responses are closely linked T- For example 5 kg in a 70kg man F- The reverse is true since fat tissue has a poor blood supply F- It can be calculated by multiplying plasma volume by 1/ (1-haematocrit) as a decimal T- The water is absorbed into the blood T- Serum equals plasma minus clotting factors F- The membrane consists largely of lipid F- The reverse is true T- Insulin increases permeability to glucose so that it is stored as muscle glycogen after a meal F- It is increased insulin is an anabolic hormone which builds up tissues with potassium and amino acids F- Carbohydrates are present eg blood group antigens T- It returns these to the blood

F- They are involved in the absorption of fat T- Increased capillary pressure leads to increased formation of tissue fluid F- It contains lymphocytes formed in lymph nodes F- Lymphatic vessels have their own propulsive smooth muscle activity T- They are formed from megakaryocytes T- This increases the tendency of blood to clot F- They have no nucleus T- They put out pseudopodia and adhere to the collagen and to one another T- By a factor of 20 or more F- Sucrose would not cross the cell membrane freely F- The sodium ions would rapidly leave the plasma T- insulin crosses capillary walls freely but does not enter cells (these properties also make it appropriate for measuring the glomerular filtration rate) F- Intracellular volume cannot be measured directly heavy water measures total body water T- As with heavy water, the different isotopes are not distinguished in the body T- The recipient will have anti-A antibody F- Group O people are universal donors T- The recipient will have anti-A antibody F- Group AB persons are universal recipients having neither anti-A or anti-B antibodies F- The recipient will not have anti-rhesus antibodies T- This causes anaemia and a raised bilirubin level T- The immature liver is slow to excrete the large amounts of bilirubin produced F- Only Rh- negative people produce anti-Rh antibodies F- The Rh antibodies attack only Rh- positive red cells F- Anti- D antibody should be given as it reacts with fetal red cells in the mother’s circulation and prevents sensitization F- Such people have no shortage of vitamin B12 T- The red cell defecit is being corrected

T-The lysed cells are being replaced T- By stimulating marrow erythropoiesis T- This confirms increased bone marrow activity F- The cells are large and well filled with haemoglobin anaemia is due to impaired cellular multiplication T- Gastric mucosa produces the intrinsic factor required for B12 absorption T- The B12 + intrinsic factor complex is absorbed here T- B12 is used in DNA synthesis which is required by all multiplying cells T- Maintenance of myelin also depends on vitamin B12 F- It depresses excitability F- Phosphate retention raises blood phosphate levels, calcium must fall to maintain a constant product T- More calcium is filtered and increases the urinary calcium phosphate solubility product F- This leads to a reduced calcium level F This lowers the bound an hence the total calcium level