Transport in Animals Flashcards
what structure is haemoglobin
- 4 amino acid chains added together
- quarternary
- an iron ion prosthetic group (congugated)
How many oxygen molecules can Hb carry?
4 (8 oxygen atoms)
oxygen +haemoglibin
oxyhaemoglibin
An S shaped graph curve?
Sigmoid
What is a sigmoid curve not
directly proportional
How and why does Haemoglobin change shape?
- The confirmation changes with more oxygen molecules
- This changes its ability to associate with further oxygen molecules.
How easy is it for the 02 molecule to attatch?
- the first one is hard
- the second and third are easily associated with haemoglobin.
- the 4th oxygen molecule finds it hard to associate because of the limited space. This is why the line plateaus
Partial Pressure Of Oxygen (Kpa)
a measure of the concentration if 02.
Fetal haemoglobin affinity?
Has stronger affinity to oxygen molecules.
Placenta?
Oxygen in mothers blood diffuses into foetus blood.
H+ ions bind to haemoglobin to create?
Haemoglobinic acid
Fetal Hb - Sugmoidal curve
shift to the left
What is Myoglobin?
A different kind of oxygen binding molecule.
Where is Myoglobin?
Found in skeletal muscles because they need more oxygen for respiration.
Myoglobin affinity?
Myoglobin has a higher affinity for oxygen than haemoglobin.
Myoglobin - how is oxygen disassociated?
After haemoglobin dissociates, Myoglobin dissociates gradually.
Myoglobin - Sigmoidal curve
Shifts to the left
percentage distribution of CO2 transport?
5% absorbed in plasma
10% binds to haemoglobin creating carbaminohemaglobin
85% CO2 dissolved into carbonic acid
CO2 + H2O =
H2CO3 carbonic acid
what does carbonic acid do?
dissociate = H+ HCO3-
What enzyme catalyses the reaction that makes carbonic acid?
Carbonic anhydrase
where do hydrogen carbonate ions go?
they diffuse from the erythrocyte into the plasma.
What do the dissociated H+ ions do?
They compete with oxygen for haemoglobin, causing oxygen to dissociate and reach respiring cells.
They bind to Hb to make haemoglobinic acid.
What do Cl- ions do?
They balance out the H+ ions that dissociated.
This is called chloride shift
explain the Bohr effect?
As CO2 concentration increases, more O2 dissociates.
Haemoglobin less saturated.
Sigmoidal curve shifts right.
Structure of a red blood cell
Biconcave
no nucleus=more room for O²
Why do larger organisms need a circulatory system?
- small SA:V ratio
- high metabolic rate
How does CO2 leave the lungs (chemical process)
- at lung tissue, HCO3- ions move into erythrocytes.
- reacts with H+ ions
- carbonic acid formed
- this broken down by carbonic anhydrase into CO2 and water.
- chloride ions move out of erythrocytes.
How does haemoglobin play a role in the reaction to form CO2 at the lungs?
acts as a buffer. absorbs extra H+ ions forming haemoglobinic acid.
When one o2 molecules bind, its easier for more to bind…
positive cooperativity
Positive cooperativity
when one molecule of O2 binds it makes it easier for the other mollecules to associate
where do lymphocytes build up?
lymph node
what happens at lymph node?
lymphocytes build up
What is present in lymph and why?
fatty acids - absorbed into lymph from villi in small intestines.
How is fluid transported in larger lymph vessels
squeezing of the body muscles.
What structure is present in lymph vessels?
valves
Where does lymph return to blood?
Right and left subclavian veins
What is the function of smooth muscle in the arterioles?
can dialate and constrict to control the volume of blood to individual organs.
why do arterioles have more smooth muscle?
to control bloodflow to capiliary beds
Name the dialation and constriction of arterioles…
vasodilation and vasoconstriction
Elastic fibres in artery walls…
recoil in between heart contractions and help to “even out surges of blood”
veins dont have a p…
pulseee
largest componants of veins vs arteries
veins: collagen
arteries: elastic fibres
What does haemolymph do?
- it does not transport 0² and C0²
- it transports food
- it transports nitrogenous waste products
- it carries cells involved in disease defence
Where is the heart on a cute tiny insect?
along the thorax and abdomen
Why is blood converted into carbonic acid?
to maintain a steep concentration gradient for co2 to diffuse into RB cells
how does pH affect the oxygen dissociation curve?
when pH decreases (gets more acidic), H+ ions will be acting as competitive inhibitors for haemoglobin so more oxygen will dissociate. curve shifts right. bohr affect
