Getting to grips with inheritance

More than a fifth of primary teachers reported low confidence in teaching about evolution and inheritance in our State of the Nation research, contrasting with just 5% with low confidence in teaching generally about plants and animals. We’d like to reassure you that you know a lot more perhaps than you realise. 

What primary children need to know about inheritance 

The basis of inheritance is simply that living things produce offspring of the same kind, but these offspring are not genetically identical with their parents or with each other (unless they are identical twins). As humans, many of our features resemble those of our parents and grandparents because genetic information is passed from one generation to the next. It’s the same for plants and other animals. 

Some things, such as skills, talents or behaviours, are not passed from a parent to its offspring genetically and must be learned.  

When we take a cutting of a plant, we’re making a clone of the plant. It will have the same genetic material as the plant it came from so will be genetically identical. If you grow a plant from a leaf, a root cutting (such as a carrot top) or a stem cutting, the plant that grows will be exactly like its parent. A bulb is also identical to the parent plant because it is not the result of sexual reproduction. Seeds are produced from sexual reproduction so contain the genes from two ‘parent’ plants. 

The background science for teachers 

Every living thing has a genome which is the complete set of genetic instructions to enable it to grow and develop. Each instruction, or gene, is represented by a specific piece of a chemical called deoxyribonucleic acid (DNA). Think of DNA like a long piece of continuous code; sections of code represent a gene. Genes determine the development and structure of organisms. Our features or appearance is determined by our genes. In sexual reproduction half of the genes come from each parent, and that’s why offspring resemble their parents but are not identical to them. We don’t need to teach primary children about DNA but it’s helpful to have a little bit of extra knowledge to explain why we’re not identical. 

The exception of course is identical twins. They result from the fertilization of a single egg that splits in two. Identical twins have exactly the same the copies of their genes so they are always of the same sex too because they have exactly the same information from each parent. Non-identical twins result from the fertilization of two separate eggs during the same pregnancy.  

If you’d like a bit more detail, look at YourGenome from the Wellcome Sanger Institute. 

Teaching ideas 

Teaching about inheritance starts with children understanding how we group and classify living things by looking at observable features. Children sort animals and plants into broad groups and refine their sorting as they develop skills to observe more closely, and compare and contrast features. Odd One Out activities are really useful for this, but make sure children can develop their skills by looking at plants and animals that are not familiar them, so they can apply their understanding.  

We’ve suggested some Odd One Out activities that your children could use to develop skills for classification and their understanding that there is a lot of variation in how living things look. 

We hope that, on reading this, you may feel reassured you know more than you perhaps realised about inheritance. All the activities on Explorify will help prompt children to explore science in an approachable way, and they all include further information to support your teaching. Check out the activities and give them a go – Happy Explorifying!

Image Credit: Ozgur Coskun via Shutterstock