Transport In Animals Flashcards

1
Q

Why do Multicellular organisms need a transport system?

A
  • They have a low surface area to volume ratio.
  • High metabolic rate.
  • Molecules such as hormones may be made in one place but needed in another.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a single circulatory system? and give an example of an animal with a single circulatory system.

A
  • Blood only passes through the heart once for each complete circuit of the body.
  • E.g Fish, The heart pumps blood to the gills (to pick up oxygen) and then on through the rest of the body (to deliver the oxygen) in a single circuit.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a double circulatory and an example of it?

A
  • Blood passes through the heart twice for each complete circuit of the body.
  • Eg mammals. Right side of the heart pumps blood to the lungs (to pick up oxygen). From the lungs it travels to the left side of the heart which pumps the blood to the rest of the body.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the advantage of the double circulatory system?

A
  • The heart can give the blood an extra push between the lungs and the rest of the body.
  • This makes blood travel faster, so oxygen is delivers to the tissues faster.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a closed circulatory system and which animals have them?

A
  • Where the blood is enclosed inside blood vessels.

- Fish and mammals have this.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a open circulatory system and which animals have this?

A
  • When blood isn’t enclosed in blood vessels all the time. Instead, it flows freely in the body cavity.
  • E.g insects, Artery opens up into to the body cavity, blood flows around the insects organs.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Arteries function and structure

A
  • adapted to carrying blood away from the heart to the rest of the body
  • thick walled to withstand high blood pressure
  • contain elastic tissue which allows them to stretch and recoil thus smoothing blood flow
  • contain smooth muscle which enables them to vary blood flow
  • lined with smooth endothelium to reduce friction and ease flow of blood
  • Endothelium-smooth-less friction with blood.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Arteriolar function and structure

A
  • branch off arteries
  • have thinner and less muscular walls
  • their role is to feed blood into capillaries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Capillaries structure and function

A
  • smallest blood vessels
  • Arterioles branch into capillaries.
  • site of metabolic exchange
  • only one cell thick for fast exchange of substances.
  • Lumen=size of red blood cell meaning diffusion distance from inside of red blood cell (HB) to tissue fluid is small.
  • Leaky
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Venules structure and function

A
  • Very thin walls.

- Join together to form veins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Veins structure and function

A
  • carry blood from the body to the heart
  • wide lumen to maximise volume of blood carried to the heart
  • thin walled as blood is under low pressure
  • contain valves to prevent backflow of blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is tissue fluid and what is it made from?

A
  • The fluid that surrounds cells in tissues.
  • Made from substances that leave the blood plasma e.g oxygen, water and nutrients.
  • Doesn’t contain red blood cells or large proteins because they’re too large to be pushed out of the capillary walls.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How is tissue fluid formed?

A
  • Diffusion.
  • Down a concentration gradient.
  • Hydrostatic pressure in the capillary is higher than the hydrostatic pressure in the tissue fluid.
  • Capillary walls are leaky.
  • Fluid is forced out of capillary from high pressure to low pressure.
  • As the fluid moves out, glucose, oxygen and small molecules leave with the fluid.
  • Large proteins and red blood cells stay in the capillary because they are too big to fit through the capillary walls.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a lymphatic system and what does it do?

A
  • A drainage system made up of lymph vessels.

- Returns the excess fluid to the blood…

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are red blood cells in (blood,tissue fluid and lymph)

A
  • Blood ✅
  • Tissue fluid ❌
  • Lymph ❌
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are white blood cells in (blood,tissue fluid and lymph)

A
  • Blood ✅
  • Tissue fluid, Very few but ✅
  • Lymph✅
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are platelets in (blood,tissue fluid and lymph)

A
  • Blood ✅
  • Tissue fluid ❌
  • Lymph ❌
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are proteins in (blood,tissue fluid and lymph)

A
  • Blood ✅.
  • Tissue fluid, very few but ✅.
  • Lymph, only antibodies but ✅.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is water in (blood,tissue fluid and lymph)

A
  • Blood ✅.
  • Tissue fluid ✅.
  • Lymph ✅.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are dissolved solutes in (blood,tissue fluid and lymph)

A
  • Blood ✅
  • Tissue fluid ✅
  • Lymph ✅
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which side of the heater pumps which type of blood where?

A
  • Right side of the heart pumps deoxygenated blood to the lungs.
  • Left side of the heart pumps oxygenated blood to the rest of the body.
22
Q

What is the external structure of the heart?

A

See page 183 in the revision guide.

23
Q

What is the internal structure of the heart?

A
  • Showbie-Webber-Transport in animals-the heart-label heart

- Answers on page 183 revision guide.

24
Q

What are the heart valves and what do they link?

A
  • Atrioventricular valve (AV) links the atria to the ventricles.
  • Semi-lunar valves (SL) links the pulmonary artery to the aorta.
25
Q

What is the function of heart valves?

A
  • They stop blood from flowing the wrong way.
  • If there’s higher pressure behind a valve, it’s forced open but if pressure is higher in front of the valve, it’s forced shut.
  • This means the flow of blood is unidirectional.
26
Q

How to perform a hear dissection.

A
  • Wear an pardon and lad gloves.
  • Place the heart on the directing tray.
  • Identify the left and right atria, the left and right ventricles and the coronary arteries.
  • Using a scalpel, cut along the heart to look inside each ventricle.
  • Cut open the atria and look inside.
  • Draw a sketch to show the valves and inside of the ventricle and atria .
  • Wash hands and disinfect work surface when finished.
27
Q

Cardiac cycle process

A
  • Ventricles are relax.
  • Atria contracts, decreasing the volume of the atria chambers and increasing the pressure.
  • This pushes blood into the ventricles through the atrioventricular valves.
  • The atria relaxes.
  • The ventricles contrast, deceasing their volume and increasing their pressure.
  • Pressure becomes higher in the ventricles the the atria which forces the atria-ventricles valves to prevent back-flow.
  • Pressure is also higher in the ventricles than in the aorta and pulmonary artery which forces poke the semi-lunar valves and blood it forced out into these arteries.
  • Ventricles and atria both relax.
  • The higher pressure in the pulmonary artery and aorta closes the SL valves to prevent back-flow into the ventricles.
  • This process repeats itself.
28
Q

How is the heartbeat controlled?

A
  • The sino-atrial node (SAN) creates an excitation.
  • This causes the atria to contract which initiated the heartbeat. (Contraction is synchronised).
  • A layer of non-conducting tissue prevents the excitation passing directly to the ventricles.
  • The electrical activity from the SAN is picked up the the atrio-ventricular node (AVN).
  • The AVN imposes a slight delay before stimulating the bundle of His (made up of purkyne fibres) between the septum.
  • The bundle of His splits into two branches and conducts the wave of excitation to the apex of the heart.
  • At the apex, purkyne fibres spread out through the walls of the ventricles on both sides.
  • The spread of excitation tiggers the contraction of the ventricles, starting at the apex.
29
Q

Why is there a delay at the AVN?

A

to ensure that the ventricles only contract after the atria have finished emptying with blood.

30
Q

Why is contraction starting at the apex good?

A
  • Allows more efficient emptying of the ventricles.
31
Q

What is the P wave causes by?

A
  • Contraction of the atria.
32
Q

What is the QRS and what is it causes by?

A
  • The main peak of the heartbeat.

- Caused by contraction of the vesicles.m

33
Q

What is the T wave cause by?

A
  • Relaxation of the ventricles.
34
Q

What does the height of the wave indicate?

A
  • How much electrical charge is passing through the heart.
35
Q

Heart rate (BPM) equation

A
  • 60/time taken for one heartbeat.
36
Q

What is tachycardia?

A
  • Heartbeat is too fast (around 120BPM).
  • At rest, it shows the Hester isn’t pumping blood efficiently.

See page 189 for diagram (revision guide).

37
Q

What is Bradychardia?

A
  • Heart bear is too slow (50BPM).
  • Can be normal for trained athletes but in others can indicate a problem with the electrical activity of the heart.

See page 189 for diagram (revision guide).

38
Q

What is an ectopic heartbeat?

A
  • An ‘extra’ heartbeat that interrupts the regular rhythm.
  • Causes by an earlier contraction or the atria than in the previous heartbeats.
    See page 189 for diagram (revision guide).
39
Q

What is fibrillation?

A
  • When the atria or ventricles completely lose their rhythm and stop contracting properly.
  • Can result in lack of pulse, fainting and death.

See page 189 for diagram (revision guide).

40
Q

What is the function and structure of Haemoglobin?

A
  • Haemoglobin is a water soluble globular protein
  • consists of two alpha and two beta polypeptide chains each containing a haem group.
  • It carries oxygen in the blood as oxygen can bind to the haem (Fe2+) group and oxygen is then released when required.
  • Each molecule can carry four oxygen molecules.
41
Q

What does the affinity for oxygen depend on?

A

The affinity of oxygen for haemoglobin varies depending on the partial pressure of oxygen which is a measure of oxygen concentration.

42
Q

How is the partial pressure determined?

A

The greater the concentration of dissolved oxygen in cells the greater the partial pressure.

43
Q

What happens when there’s a high partial pressure of oxygen(pO2)?

A
  • Oxygen loads onto Haemoglobin for for oxyhemoglobin.
44
Q

What happens when there’s a low partial pressure of oxygen(pO2)?

A
  • Oxyhemoglobin unloads it’s oxygen.
45
Q

Explain the alveoli/respiring tissue process…

A
  • Oxygen enters Blood capillaries in the alveoli in the lungs.
  • Alveoli have a high pO2, so oxygen loads onto Haemoglobin to form oxyhemoglobin.
  • When, cells respire they uses up oxygen which lowers the pO2.
  • Red blood cells delivers oxyhemoglobin to respiring tissues, where it unloads oxygen.
  • The Haemoglobin then returns to the lungs to pick up more oxygen.
46
Q

What’s does a dissociation curve show?

A
  • How saturated the Haemoglobin is with oxygen at any given partial pressure.
  • Where pO2 is high (e.g in the lungs) , Hb has a high affinity for oxygen, so it has a high saturation of oxygen.
  • Where pO2 is low (e.g in respiring tissues), Hb has a low affinity for oxygen, so it has a low saturation of oxygen.
47
Q

Why is the dissociation curve ‘S-shaped’?

A
  • When Hb combines with the first O2 molecule, it’s shape alters in a way that makes it easier for over molecules to join too.
  • But as the Hb starts to become more saturated, it gets harder for more oxygen molecules to join.
  • As a result the curve is steep in the middle (where it is easy for O2 molecules to join) and shallow at each end (where is is hard for O2 molecules to join).
48
Q

Why does fetal Haemoglobin have a higher affinity for oxygen than adult Haemoglobin?

A
  • Fetus gets blood from its mother across the placenta
  • By the time the mothers blood reaches the placenta, its oxygen saturation has decreased because some has been used up by the mothers body.
  • The higher affinity allows fetal Haemoglobin to take up more oxygen in low pO2.
49
Q

Fetal Haemoglobin adaptations…

A
  • Low pO2, so adult Hb will unload it’s oxygen.

- Higher affinity for oxygen, so it takes up oxygen at a low pO2.

50
Q

What is the partial pressure of carbon dioxide (pCO2)?

A

Measure of the concentration of CO2 in a cell.

51
Q

How does pCO2 affect oxygen unloading in respiring tissues?

A
  • When cells respire, they produce CO2 which raises the pCO2.
  • This increases the rate of oxygen upload and causes the dissociation curve to ‘shift’ right, because the saturation of blood with oxygen is lower for a give pO2.
  • This is called the Bohr effect.
52
Q

Why is an open system less effective than a closed one?

A
  • Low blood pressure

- Can’t direct the blood to where it is needed as flow is affected by body movements.