Download Chapter 6 Questions

Year 11 Human Biology
Unit 1.3 - Internal Transport
Chapter 6 Internal Transport - Solutions
FOCUS QUESTIONS
1.
Why the need for a specialised circulatory system?
Due to humans being a complex and a large organism.
2.
(a) A Labelled Heart Diagram
(b) Describe the valves & how they work.
The valves are flaps of skin & work by closing to stop backflow of blood due to the pressure of the
blood.
3.
Describe the Cardiac Cycle
The cardiac cycle, or heartbeat, is the series of events that occurs in one complete beat of the heart. It
contains the Systole (pumping stage) and diastole (filling stage).
4.
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(a) 4 differences between arteries & veins
Arteries have muscular wall that veins don't
Arteries have a smaller lumen than veins
Arteries don't contain valves where veins do
Arteries carry blood away from the heart
Have a blood pressure where veins have a steady flow
(b) Difference between capillaries & veins and arteries
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5.
Capillaries only one cell thick
Exchange of materials take place in the capillaries
Arteries, Veins, Capillaries & their structure & function
Arteries:
• Muscular Wall to pump the blood under pressure
Veins:
• Have valves
• Thin walls so muscle pressure can act on blood to force it back to heart
Capillaries:
• One cell thick
• Many capillaries
6.
Heart Chambers & Wall Size
1 - Left Ventricle - Has to push blood the furthest
2 - Right Ventricle - Has to push blood to the lungs
3 - Left & Right Atria - Pass blood into the ventricles
7.
Skeletal Movement & The Return of Blood
The skeletal muscles contract the veins causing the blood to move along the veins in one direction due
to the veins.
8.
The difference between …
(a) Systemic & Pulmonary Circulation
Systemic circulation is the blood flow to all organs except the lungs.
Pulmonary circulation goes to the lungs only.
(b) Inferior & Superior Vena Cava
Inferior Vena Cava drains blood from below the heart.
Superior Vena Cava drains blood from above the heart.
(c) Systole & Diastole
Systole (pumping stage) and diastole (filling stage) of the cardiac cycle.
9.
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Major Arteries & their locations
Carotid - Neck & Head Regions
Coronary - Heart
Subclavian - Arms
Hepatic - Liver & Stomach
Mesenteric - Intestines
Renal - Kidneys
Femoral - Legs
10.
(a) Pulse
The expansion & recall of the arteries
(b) Why a pulse can only be felt in an artery & not a vein?
No elastic wall in a vein.
(c) Why pulse is felt in arm and not anywhere else (except
neck)?
Arteries not close to the skin. Deep for protection.
11.
(a) How blood pressure is measured.
Using a sphygmomanometer which constricts the brachial artery and then slowly allows the blood to
pass through.
(b) 125/90 What does this mean?
It means that their systole pressure is 125 and their diastole is 90, Which isn't too far away from
normal.
12.
(a) What is an electrocardiogram?
Electrical charges of the heart
(b) How can they be useful to the medical practitioner?
The ECG can show abnormalities in the functioning of the heart.
APPLY YOUR KNOWLEDGE:
1. How the structure of the heart is related to it's function.
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Beats continuously
Thick wall for pumping the blood
2. What's more important, capillaries or heart?
Answer may vary, however I say heart because without the heart the capillaries wouldn't be able to
perform their function because there would be no blood.
3.
(a) Heart on left side? What would you say.
Only slightly on the left side of the midline of the body, not entirely on the left side.
(b) Why is the heart beat felt more strongly on the left side?
Because it's the side where the left ventricle is which pumps the blood to the body, so hence it has to
be stronger than the right side.
4.
(a) Fish circulation v's Humans - A Comparison.
Almost identical in terms of structures because the gills would represent our lungs and the rest of the
organs are the same.
(b) Which is more efficient - Fish or Humans?
I would say humans as we don't need to keep moving for gas exchange to occur, but it's an extremely
close call.
5.
Alcohol - From drinking to absorption.
Blood capillaries in stomach ð hepatic portal vein ð liver ð hepatic vein ð inferior vena cava ð right
atria ð tricuspid valve ð right ventricle ð Semi-lunar valve ð pulmonary artery ð capillaries in lungs ð
pulmonary vein ð left atria ð bicuspid valve ð left ventricle ð semi-lunar valve ð aorta ð carotid artery
ð capillaries in brain.
6.
How is the heart muscle supplied with oxygen?
By the coronary arteries that run over & through the heart.
7. & 8. Do Not Complete.