Mass Transport In Animals Flashcards
What does mass transport provide ?
Efficient movement of substances to and from exchange surfaces over LARGE DISTANCES
Animal mass transport e.g blood(oxygen) and circulatory system (heart)
What is the structure of red blood cell?
Quaternary protein structure
So 4 polypeptide chain
Each contains a heamoglobin and in that is the Iron Ion which is what oxygen binds to
How is oxyhemoglobin formed ?
•One oxygen molecule will combine with each hema groups
•So every Hemeoglobin molecule will combine with four oxygen molecules forming OXYHEAMOGLOBIN
There are different types of heamoglobin why?
What does affinity mean in terms of oxygen
Due to different primary aminos acid sequence so different teritaey structure so different AFFINITIES FOR OXYGEN(different oxygen transport)
Affinity-how much the hemeoglobin likes the oxygen so makes it easier or harder to bind together
How does the binding of oxygen work (in-depth if binding)
1)It is relatively difficult for the first oxygen molecule to bind to Heomoglobjn
2)however once it binds it brings about a conformational chance (it changes shapes slightly)
3)this makes it easier for following O2 to bind to the heamoglobin on the other 3 polypeptide chains
As it increases the affinity of the remaining haemoglobin group (known as cooperative binding)
What are the features of the oxyhemoglobin dissociation curve?
What is the s-shape a result of?
What does the graph show?
What does saturation mean?
Graph features
*y axis (saturation of heamoglobin with oxygen)%(100% meaning the 4 polypeptide chains filled hence why it starts to platoue)
*X-axis (conc of Oxygen ) measured in pO2 pressure or mm Hg
*standard line(is a S shape)
*Steepest part of the graph shows the greatest change in % saturation for a relatively small change in pO2.
Key points
If one of the 2 lines is further left =higher affinity
If this line is further right =lower affintiy
The s-shape is a result of the cooperative binding
it shows how the saturation of heamoglobin changes in relation to the concentration of oxygen.
Saturation -holding as much as possible e.g sponge with water
Describe and explain the loading,transport,and unloading of oxygen in relation to the oxyheamoglobin dissociation curve?
1)Haemoglobin molecule becomes fully saturated at a partial pressure of oxygen lower than that of the atmospheric O2 partial preassure
2)so they can become fully saturated in the capillaries surrounding the alveoli (loaded)
3)the resulting oxyhemoglobin then begins its journey around the circulatory system.(unloading and transport )
How does CO2 affect O affintiy?
In respiring cells they make CO2 IF ALOT dissolves into the plasma it makes it more acidic
So lower O2 affintiy
So O2 is released /dissociated more regularly to the tissue
VICE VERSA IF THE THERE WAS LESS CO2 DISSOLVED INTO THE PLASMA
Using bohr effect (graph) explain how co2 affects the concentration on the dissociation of oxyhemoglobin?
3 lines in total
-Standard line
-higher CO2 is further left
-lower CO2 is further right
Same x and y axis just like the dissociation graph and also has a s-shape
Normal adult blood has a ph of 7.4
If ph falls the curve shifts to the right
This means that for the same PO2 heomolglobin in a more acidic environment they will be less saturated with oxygen than heomglobim with a higher ph.
What causes different affinities for oxygen in heamoglobin?
Different structural arrangement
What is the general pattern of blood circulation in a mammal?
Deoxygenated blood enters through the vena cava from body into the heart(right atrium->atrioventricular valve-> right ventricle->semi lunar valve) and leaves out the pulmonary artery to go to the lungs to gain oxygen
Oxygenated blood enters via the pulmonary vein from the lungs to the heart(by passes the left atrium then the atrioventricular valve into the left ventricle past the semi-lunar valve and the it leaves the heart through the aorta
So that the blood can flow around the body
The circulatory system in mammals is described as closed and it is double circulatory what do these words mean?
Why do mamamels require a double circulatory system?
Closed (the blood remains within the blood vessels )
Double circulatory -the blood passes to the heart 2 times in each circuit there is one circuit which delivers blood to the rest of the body.
To manage pressure of blood flow.Blood flows through lungs at a lower pressure so capillaries don’t damage and reduces speed of blood flow enabling more time for gas exchange
Then oxygenated blood is pumped from the lungs back through the heart to be pumped OUT AT HIGHER PREASSURE to the rest of the body.
IMPROTANT so that blood reaches all respiring cells in the body
Key blood vessels you need to know and valves ?
Coronary arteries (cover the heart to supply the heart muscle with oxygenated blood)
These 4 blood vessels are delivering blood out and into the heart(vena cava,aorta ,pulmonary artery and pulmonary vein)
These vessels carry blood to and from the lungs (pulmonary artet and pulmonary vein)
Kidneys (renal artery and renal vein)
These major blood vessels are connected via arteries ,arterioles,veins and capillary
How are the muscles like in the ventricles and atria?
Atria -thinner walls as they don’t pump blood far(only to ventricles )
They have elastic walls to stretch when blood enters
Ventricle -thicker musclar walls for bigger contraction -> this creates high preassure so blood can flow long distances
Right ventricle has thinner walls than the left to prevent damage to capillaries
What happens during the cardiac cycle and what does the cardiac cycle maintain?
There are pressure and volume changes and associated valve movements
It maintains a unidirectional flow of blood (blood flows in one direction)
What 3 stages can the cardiac cycle be split into?
1)atriole systole - the walls of the atria contract so decreases volume and increases preassure.At that moment preassure inside the atria is greater than that of the ventricle so it forces the atrioventricle valves to open so blood is pushed into the ventricle
Ventricular systole- atria relaxes now and ventricle contract so vol decreases and preassure increases.
Due to there being higher preassure in the ventricles than in the atria it forces the AV valves to shut to prevent back flow.ONCE the ventricular pressure is greater than that of the aorta and the pulmonary vein the semi lunar valve opens and blood is forced out of the heart
Diastole=
Both the atria and ventricles relax.The pressure inside the heart decreases, causing the semilunar valves to close.Blood from the veins (vena cava and pulmonary veins) passively fills the atria.
The cycle then repeats.
(Recognise where one cycle ends and another starts)
What is the structure of artery ,atriole and veins?
(From outside to inside)
Artery
-Outer layer of collagen and elastic fibres
-thick muscular wall and elastic tissue
-folded endothelium
-small lumen
Atriole
-muscular wall
-endothelium
Veins
-Thin muscular wall
-endothelium
-large lumen
(Artery branch into atriole which connect to venuele which stem off ventricles by capillaries.)
How are arteries,atrioles and veins adapted to their function?
Arteries (carry blood away
From heart at high pressure)
Thick, muscular walls – to withstand high pressure and contract to maintain blood flow.
Elastic tissue – allows arteries to stretch and recoil, maintaining blood pressure.
Narrow lumen – keeps blood pressure high for efficient transport.
Arteriole (control blood flow to capillaries)
-Thicker layer of muscle than arteries – allows them to contract (vasoconstriction) and relax (vasodilation) to control blood flow to capillaries.
-Less elastic tissue than arteries – as they don’t need to stretch and recoil as much.
Veins(carry blood back to heart at low preassure )
-Thin walls – as blood pressure is much lower, thick walls are unnecessary.
-Large lumen – reduces resistance and helps blood flow back to the heart.
- Valves – prevent backflow of blood, ensuring one-way circulation.
Describe how tissue fluid is formed and how it is returned to the circulatory system?
At capillaries fluid passes from capillaries into the spaces around the cells bathing them in nutrients.
provides cells with useful substances such as glucose and oxygen and waste products are passed out of the cells into the tissue fluid to be removed
Formation
1. High blood
2. Forces water
3. Large proteins remain in capillary
Return
Low water potential in capillary
5. Due to (plasma) proteins;
6. Water enters capillary
7. By osmosis;
Tissue fluid is formed from blood plasma that leaks out of capillaries due to pressure differences. The process occurs as follows:
)At the arteriole end )of the capillary (high blood pressure): The hydrostatic pressure (pressure from the heart) is high, forcing water, oxygen, and nutrients out of the capillaries into the surrounding tissues.
Large molecules like proteins and red blood cells remain in the blood because they are too big to pass through capillary walls.
• The fluid that leaks out is called tissue fluid, which surrounds cells and allows exchange of substances.
2. (At the venule end )of the capillary (lower blood pressure):
• Water and some waste products (e.g., carbon dioxide) re-enter the capillaries by osmosis because the remaining blood has a higher solute concentration due to plasma proteins.
• Some excess tissue fluid drains into the lymphatic system, where it eventually returns to the bloodstream.
How are capillaries adapted for exchange?
What does higher hydrostatic preassure at the arteriole do and what does it create?
-They form capillary beds which are effiecent gas exchange surfaces between the blood and surrounding tissue.
-made up of a single layer of endothelial cells which keep the diffusion pathway short
(Capillaries connect arterioles with venules (small veins)
Higher hydrostatic pressure at the arteriole end forces blood plasma containing glucose etc out through the gaps between the endothelial cells. This tissue
fluid bathes the tissue cells.
What risk factors are associated with cardiovascular diseases?
High blood pressure.
• Smoking.
• High cholesterol.
• Diabetes.
• Inactivity.
• Being overweight or obese.
• Family history of CVD.
• Ethnic background
How is the heart (muscle )supplied with blood?
Coronary arteries
How does blood preassure compare between the pulmonary system and the systematic (body) system?
The pulmonary system has a lower pressure than the systematic (body) system
A)Which blood vessel supplies the kidney with blood ?
B)which blood vessel takes the blood away from the kidney?
A) renal artery
B)Renal vein
