Curious Kids is a series for children. If you have a question you’d like an expert to answer, send it to firstname.lastname@example.org You might also like the podcast Imagine This, a co-production between ABC KIDS listen and The Conversation, based on Curious Kids.
What happens when fruit gets ripe? – Rachel, age 3, Melbourne.
Hi Rachel. You have asked a very interesting question.
Fruit ripening is all about plants getting animals to eat the seeds that are inside their fruits.
When the animals have finished eating, they move around and drop the seeds in a different place when they do a poo. This helps the plants get their seeds to somewhere new where they can grow into a new plant.
A fruit wants to be eaten but only when the time is right
But plants need to make sure that their fruits are only eaten when their seeds are ready to be spread around.
So before the seeds are ready, the plants make sure that the fruit are not easy to see and are horrible to eat. This means the fruits may stay green and may stay hidden among the leaves, so it’s harder to pick them. They are also very hard and bitter to taste, so animals (including humans) don’t like eating them
When the seeds are ready, the fruit become ripe and good-looking, making animals keen to eat them.
When the fruit are ripe they become brightly coloured. Apples, strawberries and peaches become red, bananas become yellow and, of course, oranges become orange.
Next time you go the supermarket, look at the beautiful colours of the fruit in there and see how many different colours you can find.
Softer, sweeter and nicer to smell
At the same time as fruit change colour, they also become soft. This is because fruit are made from many tiny things called cells.
In plants, each cell has a wall. There is stuff in the cells’ walls that changes to make the fruit soft, and it is this softening that makes them juicy.
I bet the thing you most like about fruit is that they are sweet and yummy to eat. When the fruits ripen, the plant cleverly removes all of the bad-tasting stuff from the fruit and replaces them with sugars. That, of course, makes the fruit sweet and nice to eat.
The last thing that changes when fruit ripen is that they make stuff that helps them smell really nice, which makes animals and people want to eat them.
Different fruits have different stuff in them that makes them smell the way they do. That is why we can tell a pear from a strawberry, just by smell alone.