Question 1
Which component of blood transports urea?
- Red blood cells
- Platelets
- Plasma
- White blood cells
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Answer: C (1) Plasma transports urea
Question 2
List the four components of blood.
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- red blood cells, white blood cells (1)
- platelets, plasma (1)
Question 3
Describe two features that help you to identify a red blood cell in a photomicrograph.
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- no nucleus (1)
- small / round / pale in the middle / more numerous (1)
- allow biconcave shape
Question 4
State the function of (a) red blood cells, including the role of haemoglobin, (b) white blood cells, (c) plasma.
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- (a) transport oxygen (1)
- haemoglobin combines with oxygen (1)
- (b) phagocytosis and antibody production (1)
- (c) transports blood cells / ions / nutrients / urea / hormones / carbon dioxide (1)
Question 5
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanState two roles of blood clotting.
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- prevents blood loss (1)
- prevents entry of pathogens (1)