Animal transport 2.3 Flashcards by Jasmine Haynes

What are the characteristics of an open circulatory system?

-Low pressure
-No separation between blood and interstitial fluid (haemolymph)
-Dorsal tube shaped heart
-No respiratory pigment
-No respiratory gases

How well did you know this?

Not at all

Perfectly

How does the circulatory system of an insect work?

-Materials are exchanged between haemolymph and cells in haemocoel
-Heart pumps at low pressure, fluid returns slowly from haemocoel
-Fluid doesn’t travel through vessels, but bathes tissues directly

How well did you know this?

Not at all

Perfectly

How do closed circulatory systems work?

-High pressure
-Blood confined to vessels and is separate from interstitial fluid
-One or more pumps
-Large vessels divide into smaller vessels
-Material diffuses between vessels and interstitial fluid
-Respiratory pigment carries gases

How well did you know this?

Not at all

Perfectly

How does the circulatory system of an earthworm work?

-Vessels joined end to end in closed loop
-Dorsal vessel (main heart)
-Blood moves backwards to tail (ventral)
-Blood moves to head (dorsal)
-5 pseudohearts
-Capillary network in intestine
-Oxygen diffuses via moist body surface

How well did you know this?

Not at all

Perfectly

What animals use an open circulatory system?

-Insects
-Crustaceans
-Most molluscs

How well did you know this?

Not at all

Perfectly

What animals use a closed circulatory system?

-Vertebrates
-Cephalopods
-Annelid worms

How well did you know this?

Not at all

Perfectly

What are afferent arteries?

They bring blood to an organ

How well did you know this?

Not at all

Perfectly

What are efferent arteries?

They bring blood away from an organ

How well did you know this?

Not at all

Perfectly

What are the characteristics of a single circulatory system?

-Lower pressure
-Less energy to power heart
-Higher pressure to gills
-Lower pressure to body

How well did you know this?

Not at all

Perfectly

What are the characteristics of a double circulatory system?

-High pressure
-More energy to power heart
-Lower pressure to alveoli
-Higher pressure to body cells (more risk of damage)

How well did you know this?

Not at all

Perfectly

What circulatory system do insects have?

Open single circulation

How well did you know this?

Not at all

Perfectly

What circulatory system do fish have?

-Closed single circulation

How well did you know this?

Not at all

Perfectly

What circulatory system do mammals have?

-Closed double

How well did you know this?

Not at all

Perfectly

What happens when pressuring in atria>ventricle?

Left atrium contracts, pushing bicuspid open, pushing blood to left ventricle

How well did you know this?

Not at all

Perfectly

What happens when pressure in aorta>ventricle?

Blood caught in ‘cup’ of semilunar valves, closing them, preventing backflow

How well did you know this?

Not at all

Perfectly

What happens when pressure in ventricle>atria?

Left ventricle contracts, blood caught in ‘cup’ of bicuspid, bicuspid shuts, preventing backflow

How well did you know this?

Not at all

Perfectly

What happens when pressure in ventricle>aorta?

Left Ventricle contracts, semilunar valves opens

How well did you know this?

Not at all

Perfectly

What is the cardiac cycle?

A sequence of events that make up one heartbeat

How well did you know this?

Not at all

Perfectly

What are the 3 phases of the cardiac cycle?

-Ventricular diastole
-Atrial systole
-Ventricular systole

How well did you know this?

Not at all

Perfectly

What is systole?

Muscle contraction

How well did you know this?

Not at all

Perfectly

What is diastole?

Muscle relaxation

How well did you know this?

Not at all

Perfectly

What are the characteristics of ventricular diastole?

-Muscles relax
-Volume increases
-Pressure decreases
-Semilunar valves close
-Atrioventricular valves open

How well did you know this?

Not at all

Perfectly

What are the characteristics of atrial systole?

-Muscles contract
-Volume decreases
-Pressure increases
-Semilunar valves close
-Atrioventricular valves open

What are the characteristics of ventricular systole?

-Muscles contract
-Volume decrease
-Pressure increase
-Semilunar valves open
-Atrioventricular valves close

What does myogenic mean?

The heart can pump without stimulation from the nervous system

What is stroke volume?

The volume of blood expelled by the heart in one cycle

What is cardiac output?

Volume of blood expelled in a minute

What is the equation for cardiac output?

Stroke volume X BPM

What is the importance of the time delay at the AVN?

Allows time for atria to contract

What is the role of the Sinoatrial Node?

It's a pacemaker and initiates the electrical signal through the atria to Atrioventricular Node

What is the role of the Atrioventricular Node?

Causes a delay and passes impulse to ventricle through Bundle of His

What is the role of the Bundle of His?

Transmits signal to Purkinje fibres

What is the role of the Purkinje fibres?

Carries impulse through walls from apex upwards

What does an Electrocardiogram do?

Measures the electrical activity of the heart

Explain the P wave

SAN generates signal causing depolarisation of atria, leading to atrial systole

Explain the QRS peak

AVN transmitted signal via Bundle of His to Purkinje fibres. Depolarisation and ventricular systole

Explain the T peak

Repolariation of ventricle causing ventricular diastole

What can an ECG show?

-Rhythm changes -Changes as a result of a heart attack (wide QRS) -Effects of exercise

What are the key features of an artery?

-Thicker muscular walls -Narrow lumen (maintain pressure) -Smooth folded endothelium (reduce friction with blood)

Describe the Tunica externa in arteries

Collagen fibres to prevent overstretching

Describe the Tunica media in arteries

-Thick layer of smooth muscle to control diameter -Elastic fibres for strength and recoil

Describe the Tunica interna in arteries

-Single layer of smooth squamous epithelium -Folded to allow stretch

What are the key features of veins?

-Thinner muscular walls -Wider lumen -Valves

Describe the Tunica externa in veins

Low number of collagen fibres

Describe the Tunica media in veins

-Thinner layer -Some smooth muscle and elastic fibres

Describe tunica interna in veins

-Single layer of smooth squamous epithelium

Describe capillaries

Fenestrations, pores between cells allow water and solutes to pass out under pressure

What are the features of capillaries?

-Narrow -Very thin walls -Capillary beds, dense network with large cross section area, reduces pressure

What is filtered out of the capillaries?

-Water -Glucose -Amino acids -Small proteins -hormones

What are reabsorbed into the capillaries?

-Water -Urea -CO2 -Spent hormones

What do plasma proteins do to the capillaries?

Lower water potential

Where does excess fluid go?

The lymphatic system, otherwise edema occurs

What does Hb affinity mean?

How easily Hb associates/disassociates with O2

What does PPO2/CO2 mean?

Pressure exerted if it were the only gas present

What shape is the Oxygen dissociation curve?

Sigmoid, "s"

What is the importance for foetal haemoglobin to develop to adult haemoglobin?

High affinity would mean it wouldn't release O2 readily enough for respiring tissues