Pregnancy and Development
After fertilisation a fertilised egg divides and implants in the uterus, and the placenta supplies the developing baby with oxygen and nutrients.
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After fertilisation a fertilised egg divides and implants in the uterus, and the placenta supplies the developing baby with oxygen and nutrients.
- The placenta exchanges materials
- The amniotic fluid protects the foetus
- Pregnancy lasts about 40 weeks
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Pregnancy and Development?
Within Biology, which covers cells, the human body, genetics, evolution, plants and ecosystems: the science of living things, this topic explains Pregnancy and Development. Biology topics show how living things work, from the cell up to whole ecosystems, with models you can explore step by step.
Check that you can explain Pregnancy and Development in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Pregnancy and Development helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
Pregnancy and Development in detail
After fertilisation, the zygote divides to form an embryo, which implants in the uterus. The placenta develops, allowing exchange of oxygen and nutrients from the mother's blood with carbon dioxide and urea from the fetus by diffusion, without the blood mixing. The umbilical cord links the fetus to the placenta.
The amniotic fluid in the amnion protects the fetus. Pregnancy lasts about 40 weeks. Harmful substances such as alcohol, nicotine and some viruses can cross the placenta and damage the fetus. Birth involves contractions of the uterus, helped by the hormone oxytocin.
How the interactive helps you understand Pregnancy and Development
Watch the timeline in the interactive. Use any sliders or buttons it offers to change the values and see how the timeline responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Pregnancy and Development.
Real-life uses and examples
- Connect Pregnancy and Development to health, food and medicine in everyday life.
- Use Pregnancy and Development to interpret a diagram, graph or microscope image from a practical.
- Structure a longer answer about Pregnancy and Development by moving from definition to example to consequence.
Common mistakes to avoid
- Listing the steps of a process without saying how one step causes the next.
- Using everyday words, such as “energy” or “bad”, without their scientific meaning.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Pregnancy and Development
What is Pregnancy and Development?
After fertilisation a fertilised egg divides and implants in the uterus, and the placenta supplies the developing baby with oxygen and nutrients.
What are the most important points about Pregnancy and Development?
The main points are: The placenta exchanges materials; The amniotic fluid protects the foetus; Pregnancy lasts about 40 weeks.
Why is Pregnancy and Development useful?
Understanding Pregnancy and Development helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
How can I practise Pregnancy and Development?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Pregnancy and Development?
Related topics in Biology include Cell Division: Meiosis, Genes and Chromosomes, Dominant and Recessive Alleles.