animal transport Flashcards
1
Q
what’s in a mammal circulatory system
A
- blood
- blood vessels
- heart to pump blood
- a respiratory pigment (haemoglobin)
2
Q
how does an open circulatory system work
A
- heart pumps blood into spaces (haemocoel) within the body cavity
- the tissues bathe in the blood directly and exchange of materials takes place
- blood slows slowly back to the heart
- movement of muscles and valves assist with the movement of blood back to the head region
3
Q
why is there no respiratory pigment in insects
A
the blood doesn’t transport the oxygen, it’s transported by the trachea
4
Q
how does the closed circulatory system work
A
- blood is transported in blood vessels
- blood is pumped by muscular heart at high pressure resulting in rapid flow
- tissues are not in direct contact with the blood but bathe in tissue fluid which can exit out the wall of capillaries
- the blood contains pigment
5
Q
advantages of closed system
A
- blood flow is more rapid and efficient
- can be directed to where it’s needed
- more efficient oxygen delivery and nutrients and removal of waste/ co2
6
Q
2 types of closed systems
A
single and double
7
Q
what is a single closed system
A
blood only passes through the heart once before returning as the gas exchange capillaries and other body systems are in same circulation eg fish
8
Q
what is double closed system
A
passed heart at least twice before returning to same location in body as must complete separate pulmonary and system circulations eg mammals
9
Q
what does the pathway single system take
A
heart- gills- body- heart
10
Q
what does the pathway double system take
A
pulmonary circulatory system
heart- lungs- heart
systemic circulatory system
heart- body- heart
11
Q
why do mammals need double circulatory systems
A
- endothermic (produce own body heat)- high metabolic rate and high energy requirement
- their cells need a large amount of glucose and oxygen and the removal of waste products
12
Q
advantages of double
A
- the heart increases the pressure after it’s passed through the lungs- so flows more quickly to body tissues
- more efficient oxygen/nutrient delivery to tissues
- oxygen supply to heart muscle is better
- the systemic circulatory can carry blood at a higher pressure than pulmonary circulation
13
Q
Features of the mammalian heart
A
- pump for both pulmonary and systemic systems
- synchronises double pump keeping oxygenated and deoxygenated separate
- cardiac muscle- myogenic- beats from within the muscle itself- never gets tired
14
Q
Characteristics of atria
A
Thin muscle wall which exerts small pressure to push blood into the ventricles
15
Q
Characteristics of right ventricle
A
High pressure than atria
Has to push blood too the lungs so muscle is thicker
16
Q
Characteristics of left ventricle
A
Highest pressure as pumps blood brought aorta to rest of body
Muscle wall is up to 3 times thicker than right ventricle
17
Q
What does the septum do
A
Separates two sides of the heart
- stops oxygenated and deoxygenated blood mixing and ensures they get to where it needs to be
- allows different pressures to be maintained on each side
18
Q
What’s the role of the vena cava
A
Returns blood from all organs except lungs
19
Q
Role of the pulmonary vein
A
Returns blood from lungs
20
Q
Role of left atrium
A
Receives blood from the lungs and pushes it into the ventricle
21
Q
Role of atrioventricular/ bicuspid valve
A
Stops blood flowing back to the atrium as ventricle contracts
22
Q
Role of left ventricle
A
Receives blood from the atrium and pushes it to the body
23
Q
Role of aortic valve
A
Stops blood flowing back into the ventricle as the ventricle relaxes
24
Q
Role of aorta
A
Distributes blood to all organs except lungs
25
Role pulmonary artery
Distributes blood to lungs
26
Role of pulmonary valve
Stops blood flowing back into ventricle as the ventricle relaxes
27
Role of right ventricle
Recieves blood from the atrium and push it to lungs
28
Role of right atrium
Receives blood from the body organs and pushes it into the ventricle
29
What initiates the cardiac cycle
Electrical impulse
30
What initiates the cardiac cycle
Electrical impulse
31
Where is the electrical impulse initiated from
Sinoatrial node /SAN
32
Process of the cardiac cycle
1. blood enters the atria from the vena cava and pulmonary vein
2. the atria contracts and the volume decreases and pressure increases with the blood, meaning the bloos enters the ventricles down a pressure gradient
3. blood enters the ventricles through the atrio-ventricular valves (bicuspid/tricuspid)
4. the ventricles contract due to te volume decrease and pressure incease
5. blood is forced through the semilunar valves into the aorta and pumonary artery and valve then closes to prevent backflow
33
What is meant by the heart being myogenic
Can generate its own electrical impulse and does require brain stimulation
34
What are the 4 stages of cardiac cycle
Atrial diastole, ventricle diastole, atrial systole, ventricular systole
35
What is diastole
Relaxing/filling with bloos
36
What is systole
Contracting and forcing blood around two circuits
37
whats the electrical cycle process
1. SAN fires the electrical impulse to cause atrial systole
2. AVN sends electrical impulse to the bundle of his (conductive tissue)
3. electrical impulse moves down the septum, reaching purkinje fibres
4. this causes the ventricular systole and sends blood up through semi-lunar valves as they open
5. heart distole takes place
38
What do valves do
Open and close to prevent backflow
39
Why do valves open
When pressure above the valve is greater than below it
40
Why do valves close
To prevent back flow of blood when pressure beneath the valve is higher than in front of the valve
41
What is the lub-dub sound due to
The closing of atrioventricular valves then semilunar valves
42
What is the hearts internal pacemaker
Sinoatrial node (SAN)- top of right atrium
43
What is heart pressure measured by
Sphygmomano metre
44
How is electrical activity of heart measured
Using an ECG and monitored to determine correct function
45
What does the blood contain
- cells (red blood cells, white blood cells, platelets)
- plasma
46
How many oxygen molecules are carried by one haemoglobin mocelule
4
47
When does o2 associate and disassociate with haemoglobin
Associates in lungs
Disassociates in respiring tissue
48
What effects the ability of haemoglobin to uptake and release oxygen
Depends on partial pressure of oxygen in surrounding tissue
49
What is cooperative binding
O2 molecules binding with haemorrhage groups
50
What are the stages of cooperative binding
1. As the pp02 (o2 conc) increases, the diffusion gradient into the haemoglobin increases
2. Eventually 1st 02 molecule binds with one haemoglobin group and changes the shape of the haemoglobin molecule, making it easier from second molecule to attach
3. 2nd molecule attaches and change shape again
4. 3rd molecule attaches, no shape change
5. 4th molecule attaches only if there’s a large increase in ppo2
51
What is the oxygen dissociation curve
The relationship between levels of oxygen in the tissue and saturation of haemoglobin with oxygen in the blood
52
Oxygen dissociation curve explained
At low oxygen concentrations, the haemoglobin does easily load oxygen- haemoglobin releases o2 into tissue with low o2 levels
Haemoglobin picks up oxygen to form oxyhaemoglobin in tissue with high o2 levels
53
What is the Bohr effect
Effect of co2 concentration of oxygen released from haemoglobin
54
Bohr effect explained
- if co2 concentrations increases, haemoglobin releases o2 more readily- curves to right
- the Bohr effect results in more o2 being available when co2 is being produces
- when exercising, the muscles ca be supplied with more 02 for continued respiration
- the higher co2 levels, the lower amount of oxyhaemoglobin as more o2 dissociates than would normally be released at that ppo2
55
What’s the difference with foetal haemoglobin
Has slightly different structure to adult haemoglobin and greater affinity from o2 - % saturation of foetuses blood is always higher
56
What is myoglobin
Skeletal muscle oxygen-binding protein
57
Features of myoglobin
- intracelllar o2 storage- allows organisms to hold breath for extended period
- has higher affinity of o2 than haemoglobin and is more saturated at an ppo2
-oxymyoglobin does dissociated unless ppo2 is very low
58
Examples of adaptations to assist o2 release
Llama
- live at high altitude and low ppo2
Adaptations
- no. Of red blood cells increased
- haemoglobin has higher affinity for o2
Lugworm
- burrows in sand in low o2 environment- only o2 flow at high tide
Adaptations
- low metabolic rate
- pumps seawater through its burrow giving limited amount of oxygen present
- haemoglobin loads o2 very readily but only realises it at low ppo2
59
What is tissue fluid
Plasma without plasma proteins
- transports o2 and nutrients from blood to cells and waste out into blood
60
How is tissue fluid formed
when blood plasma is filtered through the walls of capillaries
The filtration process is driven by the pressure of the blood, which forces water and other small molecules out of the capillaries and into the spaces between the cells
61
how tissue fluid is used to remove waste and transports o2 to cells
Arterial end- hydrostatic pressure is higher than osmotic pressure so tissue fluid exits from capillary through pores to bathe the cells- the increased hydrostatic pressure means tissue fluid exits quickly
Venule end- hydrostatic pressure is lower than osmotic pressure due to ess volume on the venule end as nutrients enter cells lowering the hydrostatic pressure
Plasma proteins decrease the water potential so water leaves cell into capillaries as a well as co2
Remaining tissue kind removed by drainage into lymphatic system, then called lymph
62
What is the lymphatic system
- excess issue fluid ends up here and is called lymph
63
What is lymph and how is it transported
Lymph is similar to tissue fluid but has more lipids and co2
Lymph vessels are bind-ended so only allows fluid to enter
64
Where are lymph nodes located and what is their function
Located in armpits,groin, neck and gut
They produce lymphocytes which intercept bacteria and viruses and help prevent spread of microbial infection in body
65
what happens if lymph vessels become blocked
swelling can occur in affected areas due to accumulated tissue fluid
low blood proteins can affect capillary filtration which may result in fluid retention in tissue (oedema)
66
how is co2 transported into lungs
5% dissolved into the plasma
10% combined with haemoglobin to form carbamino-haemoglobin
85% transported in form hydrogen carbonate ions
67
What’s the respiratory pigment called in open systems
Haemolymph in the haemocoel
68
Structures and functions of artery
- thick wall to resist and sustain high pressure
- smooth endothelium one-cell thick smooth lining to reduce friction and minimise resistance to flow
• Thick layer of elastic fibres and smooth muscle to accommodate changes in blood flow and pressure as blood is pumped out of heart
• Outer layer of connective tissue (collagen Fibres) resist over-stretching
• Narrow lumen to maintain high pressure
• Arterioles use smooth muscle to adjust diameter
69
Structures and function of capillaries
- Thin wall, consisting of only a single layer of endothelial cells-short diffusion distance
• Narrow diameter, which slows blood flow-allow time for exchange of materials and gases
• Small gaps between endothelial cells-allows small solute molecules and ions to leak out of the capillaries
70
Structures and functions of veins
- Thinner wall (especially muscle layer) as the pressure of the blood is now reduced
• Smooth endothelium-one cell thick-smooth lining to reduce friction and minimise resistance to the flow
• Outer layer of collagen to resist stretching
• Wider lumen
- Valves along their length to ensure flow of blood in one direction under low pressure
71
parts of ECG graph
p wave- systole of atria
QRS complex- systole of ventricles
t wave- diastole of ventricles
72
How is carbon dioxide transported in the blood
1. C02 diffuses from cells into tissue fluid and then into the plasma to the red blood cells where is reacts with water to produce carbonic acid
2. The carbonic acid reactions to produce H+ ions and hydrogen carbonate
3. The hydrogen carbonate/biocarbonate diffuses into the plasma which increases the conc gradient for more co2 to enter the red blood cell
4. Chloride ions enter red blood cell to balance the charges as from the negative hydrogen carbonate ions left (chloride shift)
5. The H+ ions the reaction with HBO8 (oxyhaemoglobin) to produce 4 oxygen molecules and HHB (haemoglobinic acid)
6. The oxygen molecules are diffuses into plasma
73
why does the hydrostatic pressure decrease as the blood travels along the capillaries
water is lost through pores so resistance is increased
74
why is the osmotic pressure remaining constant as the blood travles along the capillaries
caused by plasma proteins that are too large to leave
75
why are there lymph vesels in blood supply
causes hydrostatic pressure to be greater than osmotic pressure for majority of cappillary so more tissue fluid is forced out than is reabsorbed
76
how can artery walls decrase blood flow to capillaries
the smooth muscle contracts to narrow the lumen
77
what tissues are in the transverse section of the aorta
*inner to outer
- tunica endothelium
- tunica media
-tunica externa
