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Unit 2- KA6- Transport
Blood
1-In mammals, what is transported in the
blood?
2- What is the function of red blood
cells?
3-How are red blood cells adapted to
their function?
4-Explain the function of haemoglobin in
the transport of oxygen
The lungs
Explain the function of mucus, cilia and
cartilage in the trachea and bronchi
Describe the internal structure of the
lungs. (name and role in breathing)
Larynx
1
2
3
3
4
Nutrients, oxygen and carbon dioxide
To transport oxygen around the body
- biconcave in shape: increase surface area for
diffusion of oxygen
- no nucleus: more space for oxygen
- contain haemoglobin: a pigment which allows
them to transport oxygen efficiently in the
form of oxyhaemoglobin
To transport oxygen
In lungs:
Haemoglobin binds oxygen to become
oxyhaemoglobin
In tissues:
Oxyhaemoglobin separates into haemoglobin
and oxygen
for cells to use.
Mucus: traps dirt and micro-organisms.
Cilia in the trachea: push mucus upwards and
away from the lungs towards the throat and
the oesophagus. Once in the stomach, germs
are destroyed by stomach acids.
Cartilage in the trachea and bronchi: keep main
airways open.
1- Trachea: the air passes through the larynx
and through the trachea (1).
2- Bronchus (plu. bronchi): after the trachea,
the air flow is divided within the 2 bronchi
which connect to each lung.
3- Bronchioles: bronchi which have divided
many times and are smaller in size.
4- Alveoli: air sacs.
5- Blood capillaries surrounding the alveoli
5
Where does gas exchange take place?
In the alveoli
What features of the alveoli are
important for its function?
For a more efficient diffusion of gases: alveoli
have a large surface area, thin walls and a good
blood supply.
Describe the path of oxygen in the alveoli
From cell of the alveoli wall to cells of the
capillary wall to plasma to blood cells.
Explain why the oxygen moves along that
pathway?
The heart
8- Identify the four chambers of the
heart
It diffuses from an area of high concentration
to an area of low concentration.
1
1- Right atrium (Plural atria)
2- Right ventricle
3- Left atrium (Plural atria)
4- Left ventricle
3
2
2
4
9- Describe the path of blood flow
through the heart and blood vessels
connected to it.
6
8
4
5
3
1
7
3
2
4
Describe the positions and functions of
the heart valves.
V2
2
V1
Function of Coronary artery
Blood return from organs via the vena cava (5)
and enters the right atrium (1). When the right
atrium is full, the blood is squeezed into the
right ventricle (2). The muscular wall of the
right ventricle contracts and pushes the blood
through to the pulmonary artery (6) towards
the lungs.
Blood return from the lungs via the pulmonary
vein (7) and enters the left atrium (3). When
the left atrium is full, the blood is squeezed
into the left ventricle (4). The muscular wall of
the left ventricle contracts and pushes the
blood through to the aorta (8).
When the atria are full, the blood is squeezed
into the ventricle and valves (V1) prevent its
return to the atria.
When the ventricles are full, the blood is
squeezed towards the arteries (pulmonary
artery and aorta) and valves (V) prevent its
return to the ventricles.
To bring blood to the heart muscle.
Blood vessels
Describe the structure of the arteries
Describe the function of the arteries
Describe the structure of the veins
Describe the function of the veins
Describe the structure of the capillaries
Describe the function of the capillaries
Arteries have thick, muscular walls, a narrow
central channel
Arteries carry blood under high pressure away
from the heart.
They have thinner walls and a wide channel.
Veins contain valves to prevent backflow of
blood and carry blood towards the heart.
Veins carry blood under low
pressure
Capillaries form networks at organs and
tissues, are thin walled and have a large
surface area.
They allow exchange of materials between the
blood and cells.
Intestines
How is food moved in the digestive
system.
By peristalsis: a wave of muscular contraction in
the wall of the digestive tract: muscles behind the
food contract and the muscles in front relax.
Explain how the structure of the small
intestine is related to its function.
- it is very long
- covered in finger-like villi
area
- has folds
- very thin lining of cells
of
- rich blood supply
Explain how the structure of a villus is
related to the absorption and transport
of food.
increases surface
Fast transport
nutrient to blood
- structure of villus: allows efficient absorption
of digestion products
- (1) one cell thick layer allows fast transport
of nutrient
- (2) blood capillaries: carry away glucose and
amino-acids
- (3) lymphatic vessels (lacteal): absorb
fatty acids and glycerol (the products of fat
digestion).