Transcript 6.2 Transport

6.2 - The Transport System
The heart and the blood
Draw and label a diagram of the
heart showing the four chambers,
associated blood vessels, valves and
the route of blood through the heart.
http://graphics8.nytimes.com/images/2007/08/01/health/adam/1097.jpg
Pulmonary
14
artery
Blood to the lungs
Vena Cava
10
Aorta
13
Semi lunar
12
valves
Blood from
the body
Right
Atrium
Atrio11
Ventricular
Tendon
valves
Right
Ventricle
Blood to the body
Blood
from
the
lungs
Left
Atrium
Left
Ventricle
There
Now is
test
one
yourself…..
vein not labeled - Which one?
http://leavingbio.net/CIRCULATORY%20SYSTEM/CIRCULATORY%20SYSTEM_files/image014.jpg
http://content.answers.com/main/content/img/oxford/Oxford_Sports/0199210896.valve.1.jpg
State that the coronary arteries
supply heart muscle with oxygen and
nutrients.
The heart muscle needs its own
supply of oxygen and nutrients to
pump properly. Although its
chambers are full of blood, the
heart receives no nourishment from
this blood. The heart receives its
own supply of blood through a
network of arteries known as the
coronary arteries.
The heart is such an important
organ that it must receive the
freshest most oxygenated blood
possible. So the coronary artery
is the very first branch of the
aorta.
http://www.communitymemorial.com/pics/services/CoronaryArteries.jpg
Explain the action of the heart in
terms of collecting blood, pumping
blood, and opening and closing of
valves.
1.Schwup - Diastole
The heart fills. the
muscles of the Atria and
ventricles both relax by
relaxing they draw
blood into heart. To stop
back flow into the aorta
and the pulmonary
artery the semi-luna
valves shut. The AV
valves open allowing
blood into ventricles.
2. Lub- Atrial systole
Both atria
contract valves
in the venacava and
pulmonary vein
stop back flow.
Blood gets
pushed through
AV valves to
ventricles
3. Dub - Ventricular systole
Ventricles
contract
pushing blood
to the lungs
and body.
Semi lunar
valves open
and AV valves
shut.
Outline the control of the heartbeat in terms of myogenic muscle contraction, the role of
the pacemaker, nerves, the medulla of the brain and epinephrine (adrenaline).
Take a look at this clip from Indiana Jones and the temple
of doom movie….the one where the bad guy pulls the still
beating heart out of one of his slaves……
The ability of the heart to continue beating without any
input from nerves or other chemicals is called myogenic
muscle contraction.
How does a myogenic beat work?
Sino Atrial (SA) Node or
Pacemaker
Atrio-ventricular (AV) Node
Atrio-ventricular
valves –
separates the
atria from the
ventricles
Septum – divides
the heart in 2
Purkinje fibres
http://msjensen.cehd.umn.edu/1135/Links/Animations/Flash/0027-swf_conducting_sys.swf
Chemicals (hormones) and the heart
• Look at this car commercial….
What happened to your pulse rate?
Why?
Adrenaline
speeds up the
heart beat –
gets more
oxygen to the
muscles.
Click on the coloured boxes to see effects
The
Accelerator
Nerve can
speed up the
heart beat.
Pacemaker
Sino-Atrial Node
A heart has a
normal myogenic
beat of 60 to 70
beats per minute
The Vagus
Nerve can
slow down
the heart
beat.
Explain the relationship between the
structure and function of arteries,
capillaries and veins.
Compare the thickness of the
elastic layers.
What do veins have that
arteries don’t have?
Compare the size of the
lumen.
Capillaries
• Main function is to
deliver nutrients and
oxygen to all the cells
in the body……..
….so it has to spread
out a lot,…..
….have thin walls to
allow easy diffusion,...
….be leaky to allow the
dissolved nutrients to
get to and surround the
cells.
http://www.medicalook.com/human_anatomy/organs/Blood_vessels.html
http://www.s-cool.co.uk/a-level/assets/learn_its/alevel/biology/transport/transport-in-mammals/2008-01-22_102830.gif
What have we just found out?
• Why do arteries have thick elastic walls?
Arteries work at high pressure. They have to resist this
pressure at the moment of ‘squeeze’ and return it to the
blood in between the squeezes.
• Why do veins have to have valves in them?
Veins work at low pressure. They have to work against
gravity. The valves stop the blood from falling back down to
the feet in between pumps.
• Why are capilliaries so small and why do
they have such thin walls?
Diffusion is faster over short distances and larger surface
areas.
State that blood is composed of
plasma, erythrocytes, leucocytes
(phagocytes and lymphocytes) and
platelets.
White blood cells - leucoocytes
Red blood cells - erythrocytes
Platelets
State that the following are transported by the blood:
nutrients, oxygen, carbon dioxide, hormones, antibodies,
urea and heat.
Function
Transport of
nutrients
Oxygen
Carbon Dioxide
Hormones
Antibodies
Urea
Heat
Which part of
the blood does
it?
From:
To: