Animal Transport: Module 3: Exchange and Transport Flashcards
Which blood vessel takes doexygenated blood to the heart?
The Vena Cava
Which blood vessel takes oxygenated blood away from the heart?
The Aorta
Which Blood vessel takes deoxygenated blood to the lungs?
The Pulmonary artery
(leaves from RV)
Which blood vessel brings oxygenated blood back to the left atrium?
The pulmonary vein
Where is the Tricuspid valve found?
Between the right ventricle and atrium. prevents backflow
Where is the bicuspid valve found?
between the left atrium and ventricle. prevents backflow
Where are the semi-lunar valves found?
In the Aorta and in the Pulmonary artery
Process of Ventricular Systole
1)Atria Relax, Ventricles Contract, decreasing volume and increasing pressure
2)Pressure becomes higher in ventricles than atria
3)Forces AV valves shut
1) pressure in ventricles is also higher than in Aorta and pulmonary artery
2)Forces open SL valves, blood forced out into these arteries
Process of Atrial and Ventricular Diastole
1)Ventricles and Atria relax
2)The higher pressure in Aorta and pulmonary artery closes SL valves
3)Blood starts to return to heart
4)Atria fill again due to higher pressure in vena cava and pulmonary vein
5)Increases pressure of Atria
6)Ventricles relax so pressure drops below atria pressure
7)AV valves open
8)Blood flows passively into ventricles from atria
Atrial Systole and Ventricular Diastole
1)Ventricles relax and Atria contract
2)this decreases volume of chambers, increasing the pressure
3)Pushes blood into Ventricles through AV valves
4) slight increase in ventricular pressure and chamber volume as they receive blood
Diastole
Relaxing
Systole
Contracting
Counter Current System (in fish)
Maintaining a concentration gradient where gaseous exchange takes place
Equilibrium is never reached
Diffusion of oxygen, from water into blood is constantly taking place
Process of ventilation in a fish
1)Mouth opens, buccal cavity floor lowers
2)Volume of Buccal cavity increases, decreasing the pressure
3)Water is sucked into the cavity
4)Fish closes its mouth, the floor of buccal cavity is raised again
5)Volume inside cavity decreases, pressure increases
6)Water forced out of cavity across gill filaments
7)The increase in pressure forces the Operculum (bony flap for protection) open
8)This allows water to leave the gills
What Does Myogenic mean?
it can generate a contraction from within the muscle itself and needs no nerve impulse to cause contraction
What is the Role of the Sino-Atrial Node? in the control of the cardiac cycle
To create a wave of excitation in the wall of the left atrium. The atrial wall receives this impulse, resulting in the two atria contracting simultaneously
What is the Role of the band of fibres between the atria and ventricles? in the control of the cardiac cycle
This band of fibres does not conduct the excitation from the S.A node.
This delays ventricular systole by 0.1 second To allow the atria to finish contracting and to allow all the blood to flow down into the ventricles.
What is the Role of the Atrio-Ventricular node in the control of the cardiac cycle?
The A.V node picks up excitation from the atria and after a delay of 0.1 seconds, it passes it to the conducting tissue called the Purkyne tissue grouped together into a bundle of His.
This leads down the central septum to the apex of the heart from which it radiates upwards over the whole ventricular mass. This causes the ventricles to contract from the bottom upwards.
What is the S.A node
The Sino-Atrial node is a small patch of cells which are situated in the wall of the right Atrium, near to where the venae cavae enter
What is the A.V node?
The Atrioventricular node is a patch of conducting Fibres in the septum
Outline the process of Inspiration
1)The Diaphragm contracts and becomes flat
2)External intercostal muscles contract
3)This causes the ribs to move up and out
4)This increases the volume of the Thorax
5)This decreases pressure to below atmospheric pressure
6)Air is sucked into lungs
Outline the process of Expiration
1)External Intercostal muscles relax
2)Diaphragm relaxes and goes back to original dome shape
3)causes ribs to move down and in
4)Decreases volume of thorax
5)Increases pressure above atmospheric pressure
6)Air is forced out of lungs
What is tidal volume?
The volume of air moved in and out of the lungs with each breath when you are at rest
What is Vital capacity?
The largest amount of air that can be moved into and out of the lungs
Role of goblet cells in the respiratory system
Secrete mucus. Mucus traps microorganisms and dust to stop them getting into the lungs
Role of Cilia in the respiratory system
Hair-like structures lining the airways. Beat mucus moving it up towards the throat. It is then swallowed
Elastic fibres in the respiratory system
-Helps process of breathing out
-Breathe in -> elastic fibres stretched out -> Fibres recoil to push air out
Smooth Muscle in the respiratory system
-Not in alveoli
-allow diameter to be controlled
-relax during exercise to increase dialect
Cartilage in the respiratory system
-In the Trachea and Bronchi
-Provides support
-strong but flexible
-Stops collapsing when pressure drops (breathe in)
- C shaped rings
How do you calculate breathing rate on a spirometer trace?
number of peaks/troughs per minute
(bpm)
How do you calculate rate of oxygen uptake/ min on a spirometer trace?
Measure the amount the peaks have decreased in the y direction from the first peak to one on the minute mark in dm^3
4 Adaptations of exchange surfaces
-Large surface area
-Good blood supply
-Steep concentration gradient
-Flat (to increase SA) and shorten diffusion pathway
What are the role of Sphincters in the insect transport system?
-Can be opened and closed to minimise water loss from a spiracle
What are the role of Chitin in the insect transport system?
To protect and support the tracheae from collapsing or bending
State the path oxygen takes through an insect exchange system
1) Oxygen enters through the spiracles
2)then travels through Tracheae
3)Tracheae branch into Tracheoles
4)Tracheoles spread through tissues of insect, running between individual cells. this is where gaseous exchange takes place
5)Oxygen can dissolve into moisture on surface of tracheoles to aid diffusion
Double circulatory systems
Blood passes through the heart twice for every complete circuit of the body
Open circulatory system
Blood isn’t always enosed in vessels
Pumped straight from heart into body cavity
Closed circulatory system
Blood enclosed in vessels
No direct contact between blood and cells
Heart pumps blood under pressure
Substances enter and leave blood through diffusion
Single circulatory system
-Blood passes through the heart once for every complete circuit
-blood pressure in the system drops significantly so blood returns to heart slowly (limits efficiency)
What does increasing blood pressure do to the speed?
Makes blood flow quicker
Role of Collagen in blood vessels
Provides structural support to maintain shape and volume of vessel
Role of Endothelium in blood vessels
Inner lining of cells in vessels
Role of Elastic fibres in blood vessels
Composed of elastin
Can stretch and recoil
Provided elasticity
Role of smooth muscle in blood vessels
Contracts or relaxes to alter size of lumen
What is Hydrostatic pressure
Pressure caused by water in an enclosed system
What is Oncotic pressure
The tenancy of water to move into the blood by osmosis as a result of the plasma proteins
Around - 3.3kpa
In which blood vessel is the Endothelium folded?
Why?
Artery
To allow artery to expand to maintain high pressure
Outline the process of the formation of Tissue fluid
1-5
1)At the arteriole end of the capillaries, the hydrostatic pressure inside the capillaries is greater than the hydrostatic pressure in the tissue fluid
2)The difference in the hydrostatic pressure forces fluid out of the capillaries into the spaces around the cells
3)as fluid leaves the capillaries, the concentration of the plasma proteins (oncotic pressure) increases and the water potential decreases.
4)some water re-enters the capillaries at the venule end by osmosis
5) the fluid that doesn’t go back into the capillaries drains into the lymphatic system
What is it called when oxygen bind to and leaves haemoglobin molecules?
Binds= association. Aka loading
Leave= dissociation. Aka unloading
What is PO2?
Partial pressure of oxygen
Kpa
What is the structure of haemoglobin
Large protein with quaternary structure
Made up from 4 polypeptide chains each containing a haem group
Haem group contains Iron
What happens to haemoglobins affinity as its PO2 increases?
Oxygen affinity increases
What happens to haemoglobin after the first 02 molecule binds?
It changed shape to fit other oxygen molecules easily
Conformational change
Why does feotal haemoglobin need a higher affinity for oxygen?
A foetus gets its oxygen from its mother’s blood in the placenta.
This blood may have a low ammount of oxygen.
in what 3 ways is co2 transported?
-Dissolve in plasma (more soluble than O2)
-Hydrogen carbonate ions (most common)
-Bound to haemoglobin
How does a high pCO2 effect 02?
what effect is this?
The higher the PCO2 the more that 02 dissociates
The Bohr effect
What does Carbonic acid dissociate into
hydrogencarbonate ions and hydrogen ions
Outline the Process of the carriage of carbon dioxide / the Bohr effect
1) As CO2 leaves the tissues, most of it enters the erythrocytes
2)Here it combines with water to form Carbonic acid
3)This is catalysed by the enzyme carbonic anhydrase
4)CArbonic acid dissociates (SPONTANEOUSLY) to form hydrogencarbonate ions and hydrogen ions
5)The h+ ions are absorbed by haemoglobin so the pH of the red blood cell is not lowered. so we say the haemoglobin is acting as buffer
6)The H+ ions compete with oxygen for space in the haemoglobin
7)as H+ ions combine with haemoglobin the oxygen is released to the tissues for respiration
8)The hydrogencarbonate diffuse out of the red blood cells and are carried in plasma
9)This creates a positive charge inside the red blood cell
10)Therefore Chloride ions move into the cell
11) This is called chloride shift
what provides blood to the heart
the coronary artery
how does Forced expiration differ to normal expiration
-active
-requires energy
-internal intercostal muscles contract
-ribs pulled down hard
-abdominal muscles contract forcing diaphragm up
Explain why curve for fetal oxyhaemoglobin is to the left of the adult oxyheameoglobin
1) fetal haemoglobin has a higher affinity for oxygen
2)fetal hb takes up oxygen in lower partial pressures of oxygen
3)placenta has lower partial pressures of oxygen
4) at low partial pressure of oxygen/in placenta, adult (oxy)haemoglobin will dissociate
Outline the benefits of the Bobr shift to actively respiring tissue
-actively respiring tissue requires MORE oxygen
-for aerobic respiration/to release more energy
3) actively respiring tissue produces MORE co2
4) haemoglobin involved in transport of CO2
5) less haemoglobin available to combine with O2
6) Bohr shift causes more oxygen go be released
