The diagram below represents human foetus in a uterus.
![BioF4T1P2q3](https://www.easyelimu.com/images/form_4_past_papers/Form_4_term_1_opener_2021/BIO/pp2/BioF4T1P2q3.PNG)
- Name the part labeled S.
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- Name the types of blood vessels found in the structure labeled Q.
- State the differences in composition of blood in the vessels named in (b)(i) above
- Name two features that enable the structure labeled P carry out its function.
- State the role of the part labeled R.