-
Appreciate that the development
of larger, multicellular organisms has resulted in the development of
complex organ systems and in this unit you study a description of one of these systems, the
circulatory system.
-
It
explains why blood is vital for life as it transports materials around the body
to and from different cells.
-
Possible practical and research
activities you engaged in may have included
-
Research and presentation of a report on disorders
of the blood eg haemophilia, sickle cell anaemia and leukaemia.
-
Research what to do if someone has a cut and is
bleeding badly.
-
Examine an animal heart (or model).
-
Be able to describe the
functions of components of the blood:
-
a) red blood cells
-
b) white blood cells
-
c) platelets.
-
Know that the blood
moves around the body in:
-
a) arteries
-
b) veins
-
c) capillaries.
-
Be able to describe the functions of the heart in the
pumping of blood, to include:
-
Know that blood in arteries is under higher pressure than blood in the veins.
-
Be able to explain, in terms of pressure
difference, why blood flows from one area to
another.
-
Be able to explain how the structure of a red blood cell is adapted to its
function: size, shape, contains haemoglobin, lack of nucleus.
-
Be able to describe the
function of plasma.
-
HT only: Be able to
explain how the structure of a red blood cell is adapted
to its function in terms of the small size providing a large surface area to
volume ratio.
-
HT only: Be able to
describe how haemoglobin in red blood cells reacts with oxygen
in the lungs to form oxyhaemoglobin and how
the reverse of this reaction happens in the tissues.
-
Be able to describe how the parts of
the circulatory system work together to bring about the transport of substances
around the body, to include:
-
a) arteries transporting blood away from the heart
-
b) veins transporting blood to the heart
-
c) capillaries exchanging materials with
tissues.
-
HT only: Be able to
explain how the adaptations of arteries, veins and capillaries relate
to their functions, to include:
-
a) thick muscular and elastic wall in arteries
-
b) large lumen and presence of valves in veins
-
c) permeability of capillaries.
-
Be able to identify the names and positions of the parts of the heart and describe their
functions, to include:
-
a) left and right ventricles to pump blood
-
b) left and
right atria to receive blood
-
c) semilunar, tricuspid and bicuspid valves to
prevent backflow
-
d) four main blood vessels of the heart.
-
Be able to explain why the left
ventricle has a thicker muscle wall than the right ventricle.
-
HT only: Be able to
explain the advantage of the
double circulatory system in mammals, to include:
