Soc 15: The Structure Of The Heart

Question 1

Controls body tempurature

Answer 1

Ifyou get too got the blood vessels close to the
skin get bigger (vasodilation). Blood is diverted to
the surface to allow more heat to radiate out. If
you become too cold your vessels get smaller
(vasoconstriction) to avoid heat being lost.

Question 2

Helps clot blood

Answer 2

Blood contains platelets which help clots our
dood and form scabs which help stop bleeding
and healing. In some sports small cuts are
common and so this is important.

Question 3

Transport oxygen, carbon dioxide and nutrients

Answer 3

The heart pumps oxygen around the body, which
is used in respiration and the production of
energy in the cells. The harder the muscles work
the harder the heart has to work. The system
also carries away waste products such as carbon
dioxide and deliveries nutrients and water.

Question 4

Vasodilation

Answer 4

when veins swell
up or dilate, widening of the
internal diameter (lumen) of the
blood vessel to allow increased
blood flow.

Question 5

Vasoconstriction

Answer 5

when veins
shrink down; narrowing of the
internal diameter (lumen) of the
blood vessel to decrease blood
flow.

Question 6

Vascular shunting

Answer 6

Your muscles need more blood for movement and so
move away from the organs to the muscles
• The process is called vascular shunting
Your heart starts to beat faster and your blood vessels
constrict into order to divert the blood to the muscles
• Your reflexes get faster and your muscles may tense up

Question 7

Arteries

Answer 7

• Arteries tale blood away from the heart
Arteries have thick walls and are more elastic than veins as they carry blood
is at a higher pressure than veins as they carry oxygenated blood
hannel the blood flows through, called the lumen, can widen to allow more
ad through when you so that it can reach the working muscles
I monary artery is different from other arteries as it carries deoxygenated
from the heart to the lungs

Question 8

Veins 4 characteristics

Answer 8

• Vers cary blood into the heart
• Veins have much thinner walls, are less elastic and carry blood at a lower
pressure Veins contain mary alves which helos deaygenated blood fow to the heart
• The pulmonary vein is different to other veins as it carries oxygenated blood from the lungs back to the heart

Question 9

Capillaries 4 characteristics

Answer 9

• Capillaries are microscopic vesels -just one cell thick
• At ore erd. capllanes cary auygerated blood which ransters oxygen and
nutrients to the muscles
• Atthe ather erd they cary deoy genated blood into the veins, picking up waste
products and taking them around the body to dis pose of them
• Capilaries are where gaseous exchange takes place

Question 10

What is the role of the pulmonary artery

Answer 10

Brings deoxygenated blood away from the heart to the lungs

Question 11

What is the role of the vein

Answer 11

Brings oxygenated blood to the heart

Question 12

Whats the role of the Aorta

Answer 12

Brings oxygenated blood around the body

Question 13

Importance of red blood cells?

Answer 13

• This is important to a long distance runner as their working muscles require
more oxygen when running.

Question 14

Importance of white blood cells?

Answer 14

The blood also contains transparent cells called white blood cells
They have an important function as the defence system of the body

Question 15

Importance of platelets

Answer 15

• Blood platelets are formed in the bone marrow
• Tiny fragments that clump together to help blood clot and stop bleeding
Blood is the first line of defence in the repair of a wound
When a blood vessel is cut, platelets rush to the area and swell into irregular
shapes, they become sticky and act as a plug

Question 16

Importance of plasma?

Answer 16

• The main role of plasma is to take nutrients, hormones, and proteins to the
parts of the body that need it
Cells also put their waste products into the plasma. The plasma then helps
remove this waste from the body