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Biology Module 3 > Chapter 8 - Transport In Animals > Flashcards

Chapter 8 - Transport In Animals Flashcards

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1
Q

Need for a transport system (3)

A

Size
Metabolic rate
small SA:V

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2
Q

Need for transport systems : size

A
  • large organisms cells are further from the environment so there’s a longer diffusion pathway
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3
Q

Need for transport system: small SA:V

A

Large diffusion distance = diffusion would take too long = not efficient to provide large organisms w oxygen needed and remove co2

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4
Q

Need for transport system: metabolic activity

A
  • organisms with a higher level of activity require more oxygen for aerobic respiration
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5
Q

Need for transport systems: keratin

A

Makes organisms waterproof so diffusion can’t occur thru the surface

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6
Q

Define closed circulatory system

A

Blood transported in blood vessels (veins, arteries, capillaries)

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7
Q

Single circulatory system

A

blood flows to the heart once for each complete circuit e.g. in fish it goes from heart to gills to body

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8
Q

Double circulatory system

A

blood flows to the heart twice per complete circuit e.g. in humans it goes from heart to body to heart to lungs

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9
Q

Blood flow circuits in human for one complete circuit

A

Pulmonary circuit, systemic circuit

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10
Q

Pulmonary circuit

A

Heart to lungs and back to heart

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11
Q

Systemic circuit

A

Heart to body back to heart

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12
Q

Open circulatory system

A

Blood isn’t transported in blood vessels

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13
Q

Advantages of single circulatory system

A
  • lower blood pressure = blood pressure drops as they pass through capillaries which is good = capillaries won’t explode
  • relatively simple = don’t need large organs
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14
Q

Disadvantage of single circulatory system

A

Low blood pressure = blood flow is slow = exchange is slow

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15
Q

Advantages of double circulatory system

A

Control blood pressure = - lungs need a lower blood pressure than the body so when Blood passes through the heart to the lung the pressure is lowered and it is increased as it passes through the heart to the body = blood can be pumped further

  • We need to keep our bodies warm and have high metabolic activity so this is efficient
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16
Q

Similarities between fish and mammal circulatory system

A
  • closed systems
  • both have heart, arteries
  • both carry oxygen using haemoglobin
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17
Q

Differences between mammal and fish circulatory systems

A

Fish = single circulation + mammal = double circulation
Fish = 1 atrium, 1 ventricle + mammal = 2 atria, 2 ventricles
Fish = blood passed thru 2 sets of capillaries + mammal it passes thru 1 set
Fish = lower blood pressure + mammal = blood maintained at higher pressure
Fish = less efficient at transporting substances

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18
Q

Insects circulatory system

A
  • dorsal vessel = 1 main blood vessel
  • tubular heart in abdomen pumps haemolymph ( blood in insects; into dorsal vessel
    = vessel delivers haemolymph into haemocoel (body cavity)
  • ## haemolymph surrounds organs + eventually renters heart via Ostia (1 way valves)
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19
Q

Disadvantage of open circulatory system

A
  • low blood pressure so blood flow is slow + circulation may be affected by movement
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20
Q

Why are insects able to survive w less efficient circulatory systems

A

Oxygen delivered directly to their tissues via tracheae

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21
Q

Fish circulatory system

A

Single = deoxygenated blood pumped to gills from heart = exchange site
- oxygen and co2 are exchanged w the atmosphere and blood
- oxygenated blood flows from gills to rest of body via capillaries = delivers oxygen and nutrients
- blood returns to heart (1 atrium 1 ventricle)

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22
Q

Muscle in heart

A

Cardiac muscle

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23
Q

Circulatory system in mammals

A
  • double
  • left + right side of heart w septum dividing it into 2 (left has oxygenated blood, right has deoxygenated)
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24
Q

Advantage of closed circulatory system

A
  • higher blood pressure = quicker blood flow = oxygen and nutrients delivered at faster rate + rapid removal of waste (co2)
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25
Q

LEESC

A

lumen
Endothelium
Elasticfibres
Smooth muscles
Collagen fibres

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26
Q

Capillary contents

A

LE (lumen + endothelium

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27
Q

Vein contents

A

LEESC
L umen
E ndothelium
E lastic fibres
S mooth muscles
C ollagen fibres

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28
Q

Artery contents

A

L umen
E ndothelium
E lastic fibres
S mooth muscles
C ollagen fibres

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29
Q

Artery function

A

Carry blood away from heart under high pressure

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30
Q

Artery structure

A

Elastic fibres = withstand pressure + allows them to stretch + recoil
Collagen = support + maintains shape and volume
Smooth muscle = contracts and relaxes = control blood pressure = provide strength to withstand pressure

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31
Q

Veins function

A

Carry blood back to heart. No surge from heart. Blood in veins under less pressure. Need to move against gravity

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32
Q

Veins structure

A

Thinner elastic fibres + lower thickness of muscle = no stretch + recoil bc blood pressure not as high
- valves to prevent back flow of blood
- more collagen than arteries = structural support = can carry large volumes of blood

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33
Q

Capillaries function

A

Allow substances to be exchanged between blood and surrounding cells

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34
Q

Structure of capillaries

A
  • walls = 1 cell thick = short diffusion distance
  • only large enough to allow red blood cells to travel thru in single file
  • fenestrations (gaps) = allows plasma to leak across
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35
Q

Arterials

A
  • smaller arteries
    • About to branch into the capillaries which are really delicate so they use their smooth muscles to divert the flow of the blood to different regions of the body
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36
Q

Venules

A

Smaller veins + branch into veins

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37
Q

Order of movement from heart to body to heart

A

Left side of heart (aorta) = artery = arterials = capillaries = venules = veins = right side of heart (vena cava)

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38
Q

Lumen in arteries

A

Small = maintains pressure

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39
Q

Lumen in veins

A

Large = less resistance needed bc of low pressure

Large cross section compared to circumference means fewer particles colliding with wall

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40
Q

Why’s oxygen not released until blood reaches capillaries

A
  • arteries have thick walls = no diffusion
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41
Q

What is oncotic pressure based on

A
  • conc of large plasma proteins = can’t pass out through capillary wall
  • imbalance of large plasma proteins between blood and tissue fluid results in oncotic pressure
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42
Q

What is plasma

A
  • mostly made of water = good solvent
  • some leaks out thru gaps in capillary walls + surrounds cells of the body = forms tissue fluid
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43
Q

Composition of plasma and tissue fluid

A

Similar but tissue fluid has fewer proteins
- plasma = higher concentration of plasma proteins, oxygen and amino acids
Tissue fluid = higher concentration of substances secreted by cells e.g. insulin

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44
Q

Hydrostatic pressure

A
  • pressure exerted by fluid = blood pressure
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45
Q

Oncotic pressure

A

pressure created by water potential difference due to substances moving out at the arterial end. You are left over with blood cells and large proteins because they can’t pass through the gaps in the capillaries.

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46
Q

What does tissue fluid supply

A

Supplies cells with oxygen and nutrients

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47
Q

What is the leaking of plasma from capillaries known as

A

Mass flow (movement of liquids from high to low pressure)

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48
Q

What’s in tissue fluid

A
  • plasma takes dissolved nutrients + oxygen as leaks out of capillaries
  • may have neutrophils
  • small proteins
    Water, glucose, gases, hormones
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49
Q

What can’t pass through w the plasma

A
  • large plasma proteins
  • fats
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50
Q

Arterial end

A

Front part of capillary

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51
Q

Venule end

A

Back part of capillary

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52
Q

Tissue fluid formation

A
  • arterial end = high hydrostatic pressure = forces blood fluid out of capillaries (including dissolved substances + plasma)
  • at venule end = hydrostatic pressure decreases + oncotic pressure increases = some tissue fluid moves back into capillaries
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53
Q

What does tissue fluid contain when it enters the venule end

A

Solutes and co2

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54
Q

Excess tissue fluid

A
  • enter lymph vessels = have closed ends + large pores that allow large molecules to pass thru k
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55
Q

Lymphatic system

A
  • prime function to do w immune system = has lots of white blood cells (lymphocytes) + contains more fat than blood + few proteins
  • fluid in system = lymph
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56
Q

Large molecules in lymphatic system

A
  • large molecules that can’t pass thru the capillary wall enters the lymphatic system as lymph
  • small valves in vessel walls = entry point to lymphatic system
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57
Q

Movement in lymphatic system

A
  • liquid moves along larger vessels by compression caused by body movement
  • back flow is prevented by valves
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58
Q

Lymph x bloodstream

A

Eventually revengers blood stream via veins located close to heart
- any plasma proteins that escaped are returned to blood via lymph capillaries

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59
Q

What would happen if plasma proteins weren’t removed from tissue fluid

A
  • could lower water potential = prevent re absorption of water into blood in the capillaries
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60
Q

Coronary arteries

A
  • around heart
  • provide heart with its own oxygen = blood supply to heart
  • angina + chest pains = blockage in coronary arteries
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61
Q

Heart diagram

A
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62
Q

Septum

A

Wall of muscular tissue that separates both sides of the heart

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63
Q

Septum importance

A

Ensures blood doesn’t mix between left + right sides of heart

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64
Q

Movmenent of blood in heart

A

Enters heart through vena cava -> right atrium -> right ventricle -> out of pulmonary artery to lungs where blood is oxygenated -> back down the pulmonary vein to left atrium -> Left ventricle -> pumped out of left ventricle to aorta to rest of the body

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65
Q

Importance of valves

A

Valves are important for keeping blood flowing forward in the right direction and stopping it flowing backwards. They are also important for maintaining the correct pressure in the chambers of the heart

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66
Q

Tricuspid valve

A

Between right atrium + ventricle

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67
Q

Bicuspid valve

A

Separates left atrium + left ventricle

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68
Q

2 blood vessels that bring blood to heart

A

Vena caba and pulmonary vein

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69
Q

two blood vessels taking blood away from the heart

A

; the pulmonary artery and aorta

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70
Q

Tendinous chords

A

valves are attached by these and they prevent the valves from turning inside out

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71
Q

Where is purkyne tissue and bundle of his

A

Ventricles

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72
Q

Limitations of heart dissection

A
  • hard to see some smaller structures within organ
  • specimen doesn’t reflect how tissue would look in living organism
  • if only one specimen dissected then anomalies found may be ignored
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73
Q

Cardiac output formula

A

Heart rate x stroke volume

74
Q

3 component of cardiac cycle

A
  • when atriums contract (atrial systole)
  • When ventricles contract (ventricular systole)
  • When all walls are relaxed (diastole)
75
Q

Diagram of cardiac cycle

A
76
Q

Cardiac cycle of right side

A

Same but switch aorta w pulmonary artery

77
Q

Intercalated discs

A

Distinct lines on cardiac muscle

78
Q

How do valves open and close

A

• When the pressure within a chamber/vessel exceeds that in the next chamber/ vessel the valves are forced open and the blood moves through

79
Q

Atrial and ventricular diastole

A

Atria and ventricles relax
Blood flows through bicuspid/tricuspid valves
- blood enters atria and ventricles passively

80
Q

Atrial systole

A

Atria contract
Pressure in atria increases
Blood flows thru bicuspid / tricuspid valve + ventricles fill = volume and pressure increase

81
Q

Ventricular systole

A

Ventricles contract
- volume of ventricles decrease + pressure increase
- bicuspid/tricuspid valves close
- semi lunar valves open
- blood flows into aorta + pulmonary arteries

82
Q
A
83
Q

What is happening at point A + between point A and
B

A

At A
both left atrium and left ventricle are relaxed
• Pressure sits at roughly 0 kPa
Between a A + B
Left atria contracts and empties blood into the left ventricle
- atrial systole

84
Q

What’s happening at point B

A

beginning of the ventricular systole
• Left ventricular pressure increases
• AV valve shuts
• Pressure in the left atria drops as the left atrium expands

85
Q

What is happening at point C

A

pressure in the left ventricle exceeds that in the aorta
• Aortic valve opens
• Blood enters the aorta

86
Q

Wha is happening at point D

A

diastole
• Left ventricle has been emptied of blood
• Muscles in the walls of the left ventricle relax and pressure falls below that in aorta
• Aortic valve closes
• AV valve opens

87
Q

What is happening at point E

A

expansion of the left ventricle
• There is a short period of time during which the left ventricle expands
• This increases the internal volume of the left ventricle which decreases the pressure

88
Q

Why is the maximum pressure in the ventricles substantially higher than in the atria

A

because there is much more muscle in the thick walls of the ventricles which can exert more force when they contract.

89
Q

What does cardiac output mean

A

the volume of blood that is pumped by the heart (the left and right ventricle) per unit of time

90
Q

How would being fitter effect cardiac output

A

have higher cardiac out puts due to having thicker and stronger ventricular muscles in their hearts

91
Q

When does cardiac output increase

A

When you’re exercising

92
Q

Why does cardiac output increase when you are exercising

A

so that the blood supply can match the increased metabolic demands of the cells

93
Q

What is heart rate

A

number of times a heart beats per minute
OR
number of cardiac cycles per minute

94
Q

What is stroke volume

A

volume of blood pumped out of the left ventricle during one cardiac cycle

95
Q

Stroke volume on a graph

A
96
Q

What is SAN

A

Sinoatrial node

97
Q

Rhythm of heart

A

Intrinsic rhythm

98
Q

What is the sinoatrial node

A

group of cells in the wall of the right atrium.

99
Q

Function of SAN

A

Sets rate of contraction for heart

100
Q

How does the SAN set the rate of contraction for heart

A

Initiates a wave of excitation = spreads over the walls of the atriums + causes atriums to contract

101
Q

How is pressure maintained in blood vessels v far from heart

A

Elastic tissues = recoil to maintain blood pressure

102
Q

Where is there the most elastic tissue

A

Artery walls closer to the heart = blood is initially a high pressure

103
Q

Myogenic

A

Heart initiates it’s own contraction

104
Q

Another name for sino atrial node

A

Pace maker

105
Q

Why are ventricles no affected by SAN a wave of excitation

A

Non conducting tissue in between atria and ventricle so wave of excitation can’t spread

106
Q

What is the AVN

A

Atrioventricular node

107
Q

What is the AVN

A

region of conducting tissue between atria and ventricles

108
Q

What is the bundle of his

A

collection of conducting tissue in the septum of the heart

109
Q

Describe how the beating of the heart is controlled

A

SAN initiates a wave of depolarisation that causes the atria to contract
depolarisation is carried to the atrioventricular node (AVN)
• After a slight delay, the AVN is stimulated and passes the stimulation along the bundle of His
• The bundle of His divides into two conducting fires, called Purkyne tissue, and carries the wave of excitation along them

110
Q

Why is it important that there is a slight delay

A

means that the ventricles contract after the atria = delay allows the atria to
contract = fully emptying blood

111
Q

Role of SAN in heart beat

A

sends out a wave of excitation and this spreads across both atria, causing atrial systole.

112
Q

Role of AVN in heartbeat

A

sends the wave of excitation to the ventricles after a short delay of around 0.1 - 0.2 seconds, ensuring that the atria have time

113
Q

Role of purkyne fibres in heartbeat

A

conduct the excitation down the septum of the heart and to the apex, before the excitation is carried upwards in the walls of the ventricles.
• This means that during ventricular systole, the blood contracts from its base and blood is pushed upwards and outwards.

114
Q

What are electrocardiograms used for

A

• used to monitor and investigate the electrical activity of the heart using electrodes

115
Q

What is P,QRS,T

A

P = shows atrial stimulation
QRS = ventricular stimulation
T = diastole

116
Q

Define tachycardia

A

When the heart beats too fast

117
Q

Who is normally bradycardic

A

oA lot of fit individuals or athletes

118
Q

Bradycardia

A

Slow resting heart rate

119
Q

What is an ectopic heartbeat

A

condition is caused by an early heartbeat followed by a pause

120
Q

What is fibrillation

A

irregular heartbeat will disrupt the rhythm of the heart

121
Q
A

Tachycardia = peaks too close together

122
Q
A

Bradycardic = peaks too far apart

123
Q

What is wrong

A

Small and unclear P wave indicates atrial fibrillation

124
Q

What forms when oxygen binds to haemoglobin

A

Oxyhaemoglobin

125
Q

Is the reaction between Oxygen + Haemoglobin reversible

A

Yes

126
Q

What is cooperative binding = in terms of oxygen and
haemoglobin

A

binding of the first oxygen molecule results in a conformational change in the structure of the haemoglobin molecule, making it easier for each successive oxygen molecule to bind

127
Q

Why is haemoglobin never really 100% saturated

A

• Fourth molecule = very hard to bind on = due to all these changes

128
Q

We don’t say concentration of a gas what do we say

A

Partial pressure

129
Q

What are the three main ways carbon dioxide is transported from cells

A
  • about 5% is dissolved directly in the plasma
  • About 10% is combined w haemoglobin to form carbaminohaemoglobin
  • About 85% is transported in the form of hydrogencarbonate ions HCO3 -
130
Q

How are hydrogen carbonate ions formed = describe

A

• Carbon dioxide diffuses from the plasma into red blood cells = partial pressure
• Inside red blood cells carbon dioxide combines with water to form H2C03
CO2 + H20 = H2C03
o enzyme carbonic anhydrase which catalyses the reaction between carbon dioxide and water
• Carbonic acid dissociates readily into H+ and HCO3-ions

131
Q

What happens to the hydrogen ions when carbonic acid dissociates

A

combine with haemoglobin, forming haemoglobinic acid and preventing the H+ ions from lowering the pH of the red blood cell

132
Q

What does haemoglobin act as in this situation

A

Buffer

133
Q

What happens to the hydrogen carbonate ions produced

A

diffuse out of the red blood cell into the blood plasma where they are transported in

134
Q

Why does H2CO3 form more slowly in plasma than in the cytoplasm of red blood cells

A

oplasma contains very little carbonic anhydrase

135
Q

Chloride shift

A

movement of chloride ions into red blood cells that occurs when hydrogen carbonate ions are formed

136
Q

Why does the chloride shift occur

A

• Negatively charged hydrogencarbonate are transported out of red blood cells via a transport protein in the membrane
• To prevent an electrical imbalance, negatively charged chloride ions are transported into the red blood cells via the same transport protein

137
Q

What would happen if there was no chloride shift

A

red blood cells would become positively charged as a result of a build up of hydrogen ions formed from the dissociation of carbonic acid

138
Q

Bohr shift

A

effect of increasing carbon dioxide concentration on the % saturation of haemoglobin with oxygen.

occurs when a high partial pressure of carbon dioxide causes haemoglobin to release oxygen into respiring tissues

139
Q

What does the oxygen dissociation curve show

A

shows the rate at which oxygen associates, and also dissociates, with haemoglobin at different partial pressures of oxygen (p02)

140
Q

What does saturated haemoglobin mean

A

all of its oxygen binding sites are taken up with oxygen = four oxygen molecules

141
Q

What does affinity for oxygen mean

A

Attraction to oxygen

142
Q

When haemoglobin has a high affinity…

A

binds easily + dissociates slowly

143
Q

When haemoglobin has a low affinity for oxygen….

A

binds slowly + dissociates easily

144
Q

Describe + explain shape of oxygen dissociation curve (s shape)

A
  • s shape not a linear straight line
  • curve initially not very steep = low partial pressure of oxygen so less oxygen in haemoglobin
  • once first oxygen associates with the haemoglobin it causes a conformational change in structure of haemoglobin
  • steep increase because easier for oxygen to associate with the haem group
  • graph begins to level off towards end bc majority of haem groups have oxygen molecules hinder to them = difficult for more to bind to haem groups = levels off before 100% saturation
  • as partial pressure of oxygen increases the saturation of haemoglobin with oxygen increases
145
Q

Do fetal haemoglobin have a higher or lower affinity for oxygen

A

Higher

146
Q

Draw a graph with adult and foetal haemoglobin

A
147
Q

Why does foetal blood have a higher affinity for oxygen

A

need to be able to associate with oxygen in an environment where the oxygen partial pressure is low e.g. the placenta
This is why the curve is a bit to the left because they need less oxygen to reach the same saturation. This is because the haemoglobin is adapted to absorb oxygen from a placenta which has low partial pressure. This means that it gets saturated faster.

148
Q

Where is the highest affinity to oxygen and where’s the lowest

A

Highest = lungs
Lowest = respiratory tissue

149
Q

Outline transport of oxygen

A
  • carbon dioxide diffuses from respiring cells or from the tissue fluid into the red blood cells
  • Once inside the red blood cells, carbon dioxide reacts with water to form carbonic acid. This is catalysed by the enzyme carbonic anhydrase
    CO2+H2O->H2CO3 -
  • carbonic acid is a weak acid so it immediately dissociates into H+ ions + HCO3 -
  • HCO3- immediately diffuses out of the red blood cells as a waste product
  • H+ is left, haemoglobin under the presence of CO2 dissociates with oxygen and acts as a buffer to combine with H+ ions to form haemoglobinic acid.
  • When HCO3- leaves, Chloride ions enter the red blood cells (chloride shift) to balance out the charge = electrochemical balance.
  • Oxygen that is released is taken up by the respiring cells, this happens more when there is a high concentration of co2 because oxyhemoglobin dissociates more. There is a high concentration of co2 where there are respiring cells
  • H+ ions bind to the haemoglobin and change the shape which causes it to let go of oxygen
150
Q

Why does the Bohr shift occur?

A
  • high concentration of co2 = forms carbonic acid = weak acid dissociates to form H+ ions = affect pH of red blood cells = tertiary structure change = lower affinity of haemoglobin to oxygen = takes higher partial pressure of oxygen to reach 100% saturation = more oxygen released when carbon dioxide concentration is higher
151
Q

Does myoglobin have a higher or lower affinity for oxygen compared to adult

A

Higher

152
Q

How are organisms adapted to diff levels of oxygen

A

Organisms = live in an environment with low concentrations of oxygen = have
haemoglobin with high affinity for oxygen

153
Q
A

B

154
Q
A

C

155
Q
A

C

156
Q
A

B

157
Q
A

B

158
Q
A

D

159
Q
A
160
Q
A
161
Q
A
162
Q
A
163
Q
A
164
Q
A
165
Q
A
166
Q
A
167
Q
A
168
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A
169
Q
A
170
Q
A
171
Q
A
172
Q
A
173
Q
A
174
Q
A
175
Q

ii

A
176
Q
A
177
Q
A
178
Q
A
179
Q
A
180
Q
A

Biology Module 3 (3 decks)

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