Chapter 3.2 Transport In Animals Flashcards
Why do we need a transport system ?
5
- diffusion isn’t enough
- larger organisms = diffusion distance is tooo long
- size
- SA:v —> large animals have small SA:V ratio
- level of metabolic activity = high
What are the features of a good transport system ?
5
- fluid to carry nutrient
- pump
- exchange surfaces
- tubes and vessels
- two circuits
What’s a single circularity system ?
1
- blood flows though the heart once for each circuit of the body
What’s the circulation in a fish ?
4
- hear—> gills—> Body-> heart
What’s a double circulatory system?
1
- blood flows through he heart twice for each circuit of the body
What are the advantages of a double circulatory system ?
3
- heart can maintain Blood pressure / change it according to needs
- pulmonary = low pressure & systemic circulation=higher pressure
- high pressure delivery of oxygenated blood = QUICK & EFFICIENT
- oxygenate blood reaches tissues undiluted
- deoxygenated & oxygenated blood kept separately for high conc gradient
Where to arteries carry blood ?
1
Away from heart
Where do veins carry blood ?
1
Towards heart
What’s an open circulatory system ?
1
- system in which blood isn’t kept in vessels
What’s a closed circulatory system ?
1
- blood is kept in vessels
What is the circulatory system in an insect?
5
- open circulatory system
- long muscular tube acts as heart ( just under upper surface )
- Ostia = small holes / pores = blood supply ( blood comes from body )
- long muscular tube = PERASTALSIS - to transport blood to head
- blood released to body cavity near head
How are insects circulation effected ?
1
- body movement.
What’s are the advantage of a closed system ?
3
- blood pressure is high so blood flow is high
- circulation doesn’t depend on body movements
- rapid delivery of O 2 and removal of waste
Structure of artery?
6
- small lumen
- Tunica intima ( elastic layer)
- tunica media ( Stretch and recoil )
- tunica adventia ( thick layer of collagen )
- more smooth muscle & elasticity fpr stretch and recoil
- folded endothelium - to allow artery to expand & maintain pressure
What does elastic tissue do ?
1
-stretch and recoil to accommodate pressure
What does collagen do ?
1
- prevents over stretching
What’s the order of vessels From and to the heart ?
5
- artery - arterioles- capillary -venules-veins
What’s an arterioles and how do they work ?
2
1 layer smooth muscle
- reduce blood flow elsewhere to blood flow can increase in respiring tissue !
- constriction of arterioles diverts blood to area of repairing tissue ! Yeah
Structure of capillary ?
4
- thin walls
- one layer of endothelium
- narrow lumen
- leaky walls
Structure of vein ?
3
- thin layer of elastic fibre , muscle
- large lumen
- VALVES
What’s hydrostatic pressure ?
1
- pressure exerted by fluid by pushing against the side of the vessel& container
What’s oncotic pressure ?
- pressure created by dissolved solutes
Where is hydrostatic pressure created ?
- ventricles
What’s does plasma contain ?
5
- proteins
- amino acids
- minerals
- hormones
- O2 & CO2
What doesn’t tissue fluid contain ?
2
- no protein
- no cells
How is tissue fluid formed ?
4
- atrial end of capillary : plasma leaves via gaps in capillary walls
H>O pressure
-vein end of capillary : low hydrostatic pressure so blood moves back into capillary !
O>H pressure
Where does excess tissue fluid go ?
1
- lymphatic system
Cycle of heart ?
12
- vena cava ( rhs) - right atrium - AV valve - right ventricle - semi lunar valve -pulmonary artery ( deoxygenated blood to lungs )
Pulmonary vein -left atrium - AV valve - left ventricle -left semi lunar valve - aorta ( oxygenated blood around body )
Why are walls of atria so thin?
3
- main purpose is to receive blood
- doesn’t transport blood very far ( ventricle)
- walls = thin because it’s didn’t need muscle
The Cardiac muscle is myogenic ? What does it mean ?
1
- beats of its own accord !
Structure of cardia muscle ?
2
- fibres = cross bridges
- many mitochondria !
Why is the left ventricle wall thicker than the right?
2
- L. Vent needs to push and Transport blood all around body ( systemic circulation )
- has to overcome greater distance !
What do thee tendinitis chords do in the heart ?
2
- make sure valves are in right orientation ( stop back flow)
- stop valves trying inside out !
Why are cross bridges important in cardiac muscle ?
2
- spread waves of excitation evenly
- helps to create squeezing action !
What is the Cardiac cycle ?
1
- sequence of events in one full beat of the heart
What’s is the sound of the heart beat ?
1
Valves opening and closing !
What’s the order of the Cardiac cycle ?
3
- atrial systole
- ventricular systole
- diastole
What happens in atrial systole ?
4
- Atria contracts
- ventricles relax
- blood flows to ventricle
- AV VALVE OPEN due to high pressure
What happens in ventricular systole ?
5
- ventricles contract
- atria relaxes
- blood moves to arteries
- AV VALVE CLOSES ( lub )
- SL VALVE OPENS
What happens in diastole ?
3
- ventricles relaxes
- pressure in Ventricle drops and valves close to prevent back flow
- all muscles relax
What coordinates the Cardiac cycle ?
2
- sino atrial valve
- atrio ventricular valve
What does SAN DO ?
4
- pacemaker
- stimulates Atrial systole
- sends a wave of excitation across top of atrium at regular intervals = initiates contractions
- depolarisation over atrial walls
What does AVN DO ?
4
Ventricular systole
- PAUSE ( to fill ventricle fully ! )
- waves of excitation rum down purkyne tissue to base of septum
- ventricle contract base upwards
What’s an ELectro cardio gram ?
1
- shows waves of excitation in heart
What’s -Bradychardia ? -trachychardia -atrial fibrillation -ectopic heart beat ? (8)
- bradychardia = slow heart rate
- trachechardia = fast heart rate
- atrial fibrillation= no P waste ( atrium beats faster than ventricle and doesn’t fill properly )
- ectopic heart beat = extra heart beat
What waves are detected on ECG ?
5
P QRS T
What does P wave represent ?
What’s does QRS wave represent?
T wave ?
(3)
- atrial systole
- ventricular systole
- diastole
Why does QRS have large peak that P wave ?
2
- ventricle = bigger muscle so excitation is stronger
- bigger muscle = bigger excitation !
What affinity ?
1
- strong attraction
What’s dissociation ?
1
- releasing oxygen from oxyhaemaglobin
What’s haemoglobin - structure ?
4
- 4 globular proteins : 2 alpha and 2 beta chains
- Fe2+ Haem group ( bonds to oxygen )
- HIGH AFFINITY FOR OXYGEN
- when oxygenated one O2 attached to Fe2+ group
What’s partial pressure of O2 and oxygen tension ?
1
- amount of O2 in a tissue !
What’s the Oxygen tension in lungs and respiring tissue ?
2
Lungs has high Oxygen tension and respiring tissue have Low oxygen tension
How is fetal haemoglobin different to adult haemoglobin ?
4
- higher affinity for oxygen
- maintains oxygen gradient
- oxygen moves from mum to fetus
- able to bind to oxygen even when my has dissociated from it , in low partial pressure of O2.
Where does association occur and dissociation occur ?
2
- association = lungs
- dissociation= respiring tissue
What are the 3 ways of transporting CO2 around the body?
3
- dissolved in plasma
- combined with haemoglobin
- HYDROGENCARBONATE IONs
What happens when CO2 is absorbed into red blood cell ? Process ( 5)
1- CO2 diffuses in
2-CO2 + H2O —> H2CO3
Catalysed by Carbonic anhydase
3-H2CO3 dissociates to get rid of 1 H+ ion into HCO3- and H+
4- H+ added to haemoglobin makes HHb ( haemoglobonic acid )
5-chloride ions move in to maintain charge
5- Oxyhaemaglobin dissociates at low oxygen tensions to release O2
Effect of CO2 on oxygen dissociation!
6
- high amount of HCO3- ions
-high amount of H+ ions COMPETING WITH O2 - ions for Hb
-H+ wins and O2 dissociates from Hb
-H bonds with Hb = HHb
•Some CO2 bonds directly to Hb and changes the shape of Hb ( bonds to different site ) = less affinity for Oxygen so O2 is released !
What’s the Bohr effect ?
5
- CO2 enters RBC
- carbonic acid is made and this releases H+ ions
-H+ ions make cytoplasm more acidic
-hanger IN PH effects tertiary structure = conformational change reduces affinity for O2 - haemaglobin is unable to hold on to O2 and release it !
MORE O2 RELEASED WHEN MORE CO2 IS PRODUCED IN RESPIRATION!
What happens to dissociation curve in
A) feral haemoglobin
B) Bohr effect
A) moves to the left ( more affinity for O2)
B) moves to right ( less affinity for O2)
What is the hydrostatic pressure an inciting pressure at arteriole end and Venule end ?
(4)
- Arteriole end : H>O fluid moves out
- Venule : O>H ; fluid moves in
