8) Transport in Mammals Flashcards
state 3 differences between pulmonary & systematic circulation
- pulmonary carries blood from the RIGHT side of the heart to the lungs, systematic carries from LEFT side to all body organs.
- pulmonary returns OXYGENATED blood, systematic returns DEOXYGENATED.
- pulmonary consists of pulmonary arteries, systematic consists of aorta/vena cava & arteries.
describe tunica externa (outer layer) in artery/capillary/vein
artery : present (thick layer)
capillary : absent
vein : present (thin layer)
describe tunica media (middle layer) in artery/capillary/vein
artery : present (thick layer)
capillary : absent
vein : present (thin layer)
describe tunica interna (endothelium) in artery/capillary/vein
artery : present
capillary : present
vein : present
describe valves in artery/capillary/vein
artery : absent
capillary : absent
vein : present
state direction of blood flow, pressure, and size of lumen of artery
blood flow : away from the heart to lungs
pressure : high due to pumping action of heart
size of lumen : small
state direction of blood flow, pressure, and size of lumen of vein
blood flow : to the heart, from capillary into venules –> veins
pressure : low (one way valves)
size of lumen : large
structural features of red blood cell (2)
- biconcave disc shape
- no nucleus
structural features of neutrophil (3)
- irregular/lobed nucleus
- no of lobes between 2-5
- granular cytoplasm
structural features of lymphocyte (2)
- round nucleus
- large in relation to cell
structural features of monocyte (3)
- largest cell
- clear cytoplasm
- kidney shaped nucleus
differences between blood plasma & tissue fluid
- blood plasma in arteries,capillaries,veins - tissue fluid between cells in tissues.
- blood plasma has high protein content, tissue fluid does not.
- blood plasma has high oxygen/nutrient content - tissue fluid high (arterial end), low (venous end).
- blood plasma waste content low - tissue fluid low (arterial end), high (venous end).
- blood plasma carries red blood cells and white blood cells - tissue fluid white cells which escape from the blood.
formula for aerobic respiration
glucose + oxygen = c02 + water
role of haemoglobin in transport of CO2
- haemoglobin combines w CO2.
- CO2 reacts w amine groups.
- to form carbaminohaemoglobin.
- carbonic anhydrase catalyses formation of carbonic acid.
- each polypeptide can carry a molecule of CO2.
role of carbonic anhydrase in blood
- catalyses reaction between CO2 & H20 to form carbonic acid.
- very fast reaction.
- in red blood cell.
- hydrogen ions promote oxyhaemoglobin dissociation.
- H+ forms
- H+ binds w haemoglobin to give haemoglobinic acid
- releases oxygen from haemoglobin
why is the wall of ventricle thicker than atria
the cardiac muscle has to produce more pressure
- ventricles have to pump at greater distance
why is the wall of the left ventricle thicker than that of the right
- right ventricle only has to push blood through capillaries of lungs, where resistance to flow is much less.
- than through all the capillaries of body organs supplied w blood from left ventricle.
atrial systole
- both atria contract
- valves closed in the veins (backflow of blood prevented).
- blood flows from atria to ventricles.
ventricular systole
- both ventricles contract.
- atrioventricular valves pushed shut.
- semilunar valves & pulmonary artery pushed open.
- blood flows from ventricles to arteries.
ventricular diastole
- atria & ventricles relax.
- semilunar valves & pulmonary artery pushed shut.
- blood flows from veins through atria into ventricles.
describe function sinoatrial node
- acts as pacemaker/regulates heartbeat
- releases electrical impulses
describe function of atrioventricular node
- delays impulse
- sends impulses to purkyne tissue/bundle of His
- allows atrial systole to complete before ventricular systole
3 structural features of endothelial tissue
- squamous cells
- one cell thick
- single layer
structure of haemoglobin (for uptake of oxygen)
- 4 polypeptides (alpha and beta groups)
- each w a haem group
- temporary attachment to oxygen.
- 4 molecules of oxygen.
- oxyhaemoglobin.
how is tissue fluid formed in the capillary network (3)
- higher pressure of blood
- filtration of blood
- pushing out plasma
- plasma proteins not filtered out but amino acids/salts are.
who do red blood cells not leave the capillary (2)
- too large
- cannot pass through endothelial pores/cells
what is double circulation system
- blood travels through the heart twice
- through pulmonary & systemic circulation
stages in the cardiac cycle (6)
- wave of excitation spreads from SN
- atrial walls contract
- wave of excitation enters AVN
- impulse delayed for fraction of a second
- wave passes down Purkyne tissue
- ventricles contract
describe structure of red blood cells
- no nucleus’
- biconcave disc shape
- no organelles
how is the structure of capillary wall related to its functions
- one cell thick
- endothelial cells / pores
- short distance for diffusion
Explain why the concentration of chloride ions in the blood plasma of deoxygenated
blood is lower than in the plasma of oxygenated blood.
- HCO3- ,pass out of red blood cells (into the plasma to increase concentration in
deoxygenated blood) ; - chloride ions pass into red blood cells ;
- to replace the, negatively-charged HCO3- ;
4 . chloride shift
why is it important that the AVN delays the impulse
- atria and ventricles do not contract at same time
- ventricles contract AFTER atria
tunica media consists of ?
- elastic fibres
- collagen
- smooth muscle
where is SN found
wall of the right atrium
State the precise site in the mammalian body where haemoglobin molecules bind with
oxygen.
alveolar capillary
