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Science Year 5 Practice 2 Humans

Human Blood Circulatory System
2.2
1. There are three main parts in human blood circulatory system which are:

Heart – The organ that Lungs – Place of Blood vessel – Transports blood to the whole
pumps blood to the exchange between body. Blood vessel is a passage tube for blood
lungs and the whole oxygen gas and f ow. Blood transport oxygen, nutrients, water
body. carbon dioxide gas and waste substances.
occurs.
Blood vessel
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Blood

2. Diagram below shows a cycle of blood circulatory system. Blood will return back to the heart two
times in each cycle. Once to send blood to the lungs, and another one is to send the blood to the
whole body.

1. ① When we inhale, ② This blood contains more
oxygen enters oxygen and the heart pumps
the lungs and is the blood rich in oxygen to
4. absorbed into the the whole body. This blood
blood vessels. is known as the blood rich in
oxygen.
Blood
Lungs vessel
④ The heart will pump
the blood rich in ③ After the body uses up all of
carbon dioxide to the oxygen, carbon dioxide is
the lungs. The lungs produced and absorbed into
remove carbon the blood. This blood is known
2. dioxide when we as blood rich in carbon dioxide.
exhale.

Legend:
3. Heart blood rich
in oxygen
blood rich in
carbon dioxide

Human body
3. Other than transporting oxygen gas to the whole body and transport carbon dioxide gas to the lungs
to be removed, blood also transport other substances.
4. Nutrients which are absorbed from the intestines will be transported to the whole body through the
blood circulatory system.
5. Waste products such as urea and toxic substances will be transported through the blood circulatory
system to the excretory organs such as kidneys to be removed from the human body.

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02 Practice Go Science Yr5.indd 8 29/09/2021 9:17 AM