6. Constituents of Blood and Oxygen Delivery Flashcards
the PASSAGE of FLUID through the CIRCULATORY SYSTEM or LYMPHATIC System to an ORGAN or TISSUE,
usually referring to the DELIVERY OF BLOOD TO A CAPILLARY BED IN TISSUE is known as:
PERFUSION
(achieved by the heart providing sufficient cardiac output)
depending on size how much BLOOD do we have
4-6L
the PLASMA PORTION of BLOOD (60%) consists of:
(other 40% of blood is cells and platelets)
90% WATER
10 % DISSOLVED MATERIALS
- glucose, ions, salts, proteins, hormones, gases, ph buffer, waste
RED BLOOD CELLS
what do they carry?
where are they destroyed after 120 day lifespan?
how many in one drop of blood?
carry O2 and CO2
destroyed in the LIVER
(5 million in one drop of blood)
how do LEUKOCYTES (WHITE BLOOD CELLS) DIFFER to ERYTHROCYTES (RED BLOOD CELLS)
- LARGER
- have NUCLEUS
- NO HAEMOGLOBIN
- function in IMMUNE RESPONSE
What are the 5 TYPES of LEUKOCYTES
- NEUTROPHILS
squeeze through capillary walls into tissue fluid, phagocytosis - MACROPHAGES
release white blood cells growth factors causing a population increase for wbc - LYMPHOCYTES
fight infection - T CELLS
attack cells containing viruses - B CELLS
produce antibodies.
antigen-antibody complex phagocytosed by macrophage
which LEUKOCYTE RELEASES WHITE BLOOD CELL GROWTH FACTORS to increase the population number
MACROPHAGES
what do PLATELETS do
help STOP BLEADING
- stick to the opening of damaged blood vessesl, attract more and form a PLUG to SEAL BROKEN BLOOD VESSEL
PLATELETS SURVIVE for 10 days before they are REMOVED BY…
the LIVER and SPLEEN
what is the name for the inability to clot aka ‘bleeders disease’
Haemophillia
where are RED BLOOD CELLS and WHITE BLOOD CELLS MADE
BONE MARROW
RED: RED MARROW
WHITE: YELLOW MARROW
what classes as EXTERNAL RESPIRATION
PULMONARY VENTILATION & PULMONARY DIFFUSION
what classes as INTERNAL RESPIRATION
TRANSPORT TO/FROM TISSUE
CAPILLARY DIFFSUION and EXCHANGE
how do BRONCHIAL and VASCULAR TREES provide MAXIMUM SURFACE AREA for gas exchange
they are fundamentally LINKED to one another
what happens in INSPIRATION/INHALATION
ACTIVE PROCESS
- DIAPHRAGM FLATTENS (CONTRACTS)
- EXTERNAL INTERCOSTAL MUSCLES CONTRACT
- VOLUME INCREASES, PRESSURE DECREASES
(Boyle’s law: pressure x volume = constant)
air moves IN
what happens in EXPIRATION/EXHALATION
PASSIVE process
- DIAPHRAGM RELAXES and recoils back up
- EXTERNAL INTERCOSTAL MUSCLES RELAX
- VOLUME DECREASE, PRESSURE INCREASE
air moves OUT
when does EXPIRATION become an ACTIVE process
in HEAVY EXERCISE
- Internal intercostal muscles pull ribs back down to increase rate
BRONCHOCONSTRICTION is the activity of which nervous system
PARASYMPATHETIC activity
(or due to cold or allergens)
BRONCHODILATION is the activity of which nervous system
SYMPATHETIC activity
- adrenaline/noradrenaline
(Also exercise or B2-agonists ie salbutamol for asthmatics)
how is VASCULAR RESISTANCE and PRESSURE in the PULMONARY SYSTEM as opposed to circulatory system
LOWER RESISTANCE due to LOWER PRESSURE
(therefore have thinner smooth muscle layer in the wall of pulmonary vessels)
which LAW is the following:
‘TOTAL PRESSURES OF A MIXTURE OF GASES EQUALS THE SUM OF THE PARTIAL PRESSURES OF THE INDIVIDUAL GASES IN THAT MIXTURE’
DALTON’S LAW
which LAW states that
WHEN A MIXTURE OF GASES IS IN CONTACT WITH A LIQUID, EACH GAS WILL DISSOLVE IN THE LIQUID IN PROPORTION TO ITS PARTIAL PRESSURE.
the AMOUNT OF GAS THAT DISSLVES IN A LIQUID is also DEPENDENT UPON THE SOLUBILITY OF THE GAS AND THE TEMPERTATURE OF THE LIQUID
HENRY’S LAW
does Venous blood or Alveolar air have higher PCO2
Venous blood as some CO2 remains in blood (residual)
what CONSTRICT/DILATE to REGULATE AIR FLOW
BRONCHIOLES
what CONSTRICT/DILATE to REGULATE BLOOD FLOW
ARTERIOLES
how much of BLOOD is BOUND to HAEMOGLOBIN
98%
- 2% dissolved in blood
where is CO2 in the body
60-70% DISSOLVED in BLOOD AS BICARBONATE IONS
(CO2 + H2O -> H2CO3 -> H+ + HCO3-)
7-10% DISSOLVED in BLOOD
up to 20% BOUND to HAEMOGLOBIN (to globin - polypeptide chain)
what is CHLORIDE SHIFT
MAINTAINS BLOOD PH
exchange
- Cl- moved INTO RBC
- HCO3- moved INTO BLOOD PLASMA as BUFFER
what is BOHR EFFECT
if too ACIDIC (HIGH H+)
O2 RELEASED from HAEMOGLOBIN (right shift)
H+ BINDS to HAEMOGLOBIN
what is HALDANE EFFECT
CO2 BINDS BETTER to DEOXYHAEMOGLOBIN (HbH) than to OXYHAEMOGLOBIN (HbO2)
so binding of O2 to Hb causes the RELEASE of CO2
or
Binding CO2 to Hb causes RELEASE of O2
when does the OXYHAEMOGLOBIN DISSOCIATION CURVE SHIFT to the RIGHT
DECREASED AFFINITY and more O2 RELEASE
due to
- DECREASED pH (more acidic) (Bohr effect)
- INCREASED CO2
- INCREASED TEMP
when does the OXYHAEMOGLOBIN DISSOCIATION CURVE SHIFT to the LEFT
INCREASED AFFINITY and more O2 LOADING
due to
- INCREASED pH (less acidic)
- DECREASED CO2
- DECREASED TEMP
in MUSCLE CELLS, what CARRIES O2 TO the MITOCHONDRIA (from the haemoglobin)
MYOGLOBIN
there is a STEEP SATURATION CURVE for MYOGLOBIN which means
very EFFICIENT DELIVERY of O2 TO MITOCHONDRIA
what does the HEART use as its PRIMARY SUBSTRATE for Oxidative Metabolism to produce ATP
FREE FATTY ACIDS
in HEAVY EXERCISE what can be used to give ATP instead of free fatty acids
LACTATE
is ISCHAEMIA what is used to give ATP (small amount) instead of free fatty acids
GLUSOSE via ANAEROBIC GLYCOLYSIS
(also use glucose following a meal)
CARDIOMYOCYTES have the LARGEST NUMBER of..
MITOCHONDRIA
- for efficient ATP synthesis from free fatty acids
what do CARDIOMYOCYTES require adequate levels of for CONTRACTION
CALCIUM
(and low calcium for relaxation)
how is BLOOD FLOW DIVERTED during EXERCISE
SKELETAL MUSCLE need more
Gut needs less so diverted from gut
what are the site of GREATEST REGULATION of BP and ABSORBS the GREATEST PRESSURE DROP
ARTERIOLES
during EXERCISE, INITIAL CHANGE in PULMONARY VENTILATION RATE is due to…
later change is due to…
initial: NEURAL INPUTS
later: due to CHANGES in CHEMICAL COMPOSITION of BLOOD GASES/pH
ventilation response may even increase before, anticipating activity
why can HYPERVENTILATION lead to Unconsciousness
REDUCES PCO2 and so Blood pH can INCREASE (alkaline)
when does LACTATE come
as soon as RESPIRATORY RATE INCREASES
why may ASTHMA LIMIT ABILITY to EXERCISE
CONSTRICTS AIRWAYS
why may FIBROSIS LIMIT ABILITY to EXERCISE
lungs have FIBROUS TISSUE laid down
- STIFFER LUNGS
- LESS ELASTIC
- more DIFFICULT to BREATHE
what does PULMONARY HYPERTENSION include
HIGH BP in ARTERIES IN LUNGS
THICKENING of PULMONARY ARTERIES so become
LESS COMPLIANT / STRETCHY during systole
- REDUCED BLOOD FLOW
- more work for right side of heart
leads to heart failure and death
- poor gas exchange
- limited ability to carry out basic exercise
what can lead to REDUCED BLOOD FLOW in a LIMB
PERIPHERAL ARTERIAL DISEASE (PAD)
= reduced metabolites and O2 (may cause ischaemia)
what is HAEMOGLOBINOPATHY
conditions caused by a QUALITATIVE STRUCTURAL ABMORMALITY of the GLOBIN POLYPEPTIDE CHAINS in HAEMOGLOBIN
- result from genetic mutations of chains
what is THALASSEMIAS
conditions caused bu a QUANTITATIVE ABNORMALITY in GLOBIN CHAIN in HAEMOGLOBIN
(ie reduced or no protein production)
what are ANEAMIAS
REDUCTION in the NUMBER of ERYTHROCYTES meaning reduced O2 TRANSPORT
what is SICKLE CELL DISEASE
ABNORMAL, CRESCENT MOON SHAPED RED BLOOD CELLS due to defective haemoglobin
due to MUTATIONS of the BETA-GLOBIN CHAIN on Chr. 11, HAEMOGLOBIN S forms
- Glutamic acid is replaced by Valine
SICKLE CELLS DIE EARLY, causing SHORTAGE of RBCs
SICK CELLS may get STUCK and BLOCK SMALL BLOOD VESSELS causing pain, poor o2 transport, ischaemia
