Ch.4.circulatory system
Transcript of Ch.4.circulatory system
Chapter 4(Biology)
Circulatory system
Objective Be able to explain how the heart pumps blood around the body
OutcomesLevel 4 – Put the labels in the correct place to describe how oxygenated and deoxygenated blood moves around the bodyLevel 5 – Explain how and why pulse rate changes when you exercise/sleep using key words to do with respiration.
Circulation
Look at the word CIRCULATION
What does the first part of the word sound like?CIRC…….
CIRCULATIONcir·cu·la·tion
CIRCLE CIRCULAR CIRCULATE
Arteries•Have thick walls•Carry oxygenated (red) blood away from the heart to the body•Blood moves at high pressure Veins
•Have thin walls•Carry deoxygenated (blue) blood to the heart from the body.•Have valves (stop blood flowing back)
Capillary•Have thin walls•Walls are one cell thick•Substances are able to pass in and out of the blood.
RED BLOOD CELLS
THIN CELL WALL
BODY CELLS
The dissolved food and oxygen needed for respiration are carried around the body by the circulation system.
The circulation system includes the blood, blood vessels, the heart and the lungs.
body’scells
body’scells
lungslungs
Which part of the circulation system carries dissolved food and oxygen to the
body’s cells?
body’scells
lungslungs
Blood travels from the heart to the lungs
Blood picks up oxygen from the lungs and gives out carbon dioxide
Oxygenated blood travels back to the heart
Oxygenated blood travels from the heart to the body
Body cells use oxygen and give blood CARBON DIOXIDE
DEOXYGENATED blood travels from the body to the heart
body’scells
body’scells
lungslungs1. Blood travels from the heart to the lungs
2. Blood picks up oxygen from the lungs and gives out carbon dioxide
3. Oxygenated blood travels back to the heart
4. Oxygenated blood travels from the heart to the body
5. Body cells use oxygen and give blood CARBON DIOXIDE
6. DEOXYGENATED blood travels from the body to the heart
The blood carries oxygen and dissolved food to all the body’s cells so that respiration can take place.
Blood
RED BLOOD CELLS
THIN CELL WALL
BODY CELLS
usefulsubstances
wasteproducts
Plasma• This is the yellowish liquid portion of the
blood that contains electrolytes, nutrients and vitamins and hormones as well as red blood cells, white blood cells and platelets.
Red blood cells• Red blood cells carry oxygen from your lungs
to your heart, and then to your muscles.• They help to remove the carbon dioxide from
the body.• They contain haemoglobin, which combines
with oxygen.• They have no nucleus and a biconcave
shape to give the most space for oxygen.
Red blood cells• They are like a
mailman.• Why?
White blood cells
White blood cells• They are part of the immune system• White blood cells protect the body from
infections.• There are several ways they can do this
– Phagocytosis:
White blood cells• Certain types of white blood cells produce
antibodies to fight infections• White blood cells are clever – certain white
blood cells called lymphocytes can produce “memory cells” so that if the body is infected again it can fight it quickly.
• This is how injections work:
White blood cells• They are like a policeman.• Why?
Platelets• http://humanbiologylab.pbworks.com/w/
page/50314371/Hemostasis• These help the blood to clot if you get a
cut.
Platelets• They are like a doctor.• Why?
Blood• Red blood cells –
44%• Plasma – 55%
(90% water)• White blood cells –
0.05%• Platelets - 0.05%
Blood is a mixture of different types of cells suspended in a straw coloured liquid called plasma.
The main function of blood is to: carry oxygen and nutrients to the body’ cells; remove waste products; and protect the body against infection.
Different components of the blood carry out different roles.
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Word bank: roles, cells, plasma, infection, blood, waste, oxygen,
The heart is a DOUBLE PUMP:
1st - blood is pumped to the lungs & returns to the heart,2nd - blood is pumped to respiring muscles & back to the heart again.
1. Deoxygenated blood is pumped from the heart to the lungs
2. The blood receives oxygen and is pumped back to the heart
4. The oxygen leaves the blood to be used for respiration in the body and the blood goes back to the heart
3. The oxygenated blood is then pumped to the rest of the body
The heart is made of very special muscle called cardiac muscle.
This is because it has to keep beating for the whole of a person’s life!
If you tried to do the same action repeatedly (like the heart does), your muscles would get tired and after a while stop working.
Your beating heart
For example, if you keep clenching and unclenching your hand, it will get tired and may even start to get cramp.
Why is it important for respiration that the heart keeps beating?
EXERCISE Stand up and count pulse for 1
min.When I say go…..do star jumps
PROPERLY for 1 minuteWhen I say stop – stand still again
and count pulse for 1 minute
EXERCISE The body needs to release more energy: so oxygen and sugar (glucose) need to reach muscle cells quickly; so blood is pumped around the body faster; so the pulse is faster.
What happens to the pulse rate whilst someone is running and why?
Different types of activity
What happens to the pulse rate whilst someone is sleeping?
plenary – Wordframe about circulatory system
Circulation