Category Science

Most new plants will grow better if they do not have to share water, soil and sunlight with a bigger plant. When seeds are made, the plant tries to spread its seeds as far away as it can. Animals, the wind and water are used to move seeds to new places.

Some seeds are blown by the wind.

Dandelion seeds are very light and are carried by the wind. They float on the wind instead of falling straight down.

Coconuts are carried away by the sea.

Coconuts have a padded waterproof case so they can travel long distances by sea.

Continue reading “How seeds travel”

Some seeds are so tiny they look just like specks of dust. Others are as big as footballs! Most seeds do not start to grow as soon as they are made. They need to be kept safe inside a fruit or seed case until it is the right time to grow into a new plant.

Most seeds grow inside a seed case or fruit.

The casing that protects a seed can be hard like a nut shell, or soft like an apple or tomato. Each seed case is adapted to help keep the seed safe.

Beans and nuts are seeds.

Inside each seed is a baby plant. This tiny plant already has a root and shoot and the food it needs to begin to grow.

Some trees have two kinds of flowers on them – male flowers and female flowers. These catkins are male flowers. They are covered with pollen. The same tree also has small female flowers.

A holly tree can be male or female.

Holly trees or bushes are either all male or all female. Both male and female holly trees have white flowers. Berries only form on the female trees. To make new plants, there must be a male and female holly tree growing near each other. Insects carry pollen from the male to the female tree.

Both male and female flowers grow on a pine tree.

The male flowers are usually red or purple and the female flowers are often yellow or white. The female flower will become a pine cone if it is fertilized.

Most trees and bushes have flowers.

Some trees have flowers to attract insects, while others use the wind to spread pollen. Trees that use the wind usually have green, feathery flowers that hang from the tree.

Some flowers need birds to help them make seeds. Just like insects, some birds go to brightly coloured flowers in search of nectar. The pollen rubs off onto their beaks and feathers. They carry the pollen to other flowers.

Colourful flowers attract birds.

Birds are heavier than insects and a bird’s beak is hard. Because of this, bird-pollinated flowers are firm and tough. Birds have a poor sense of smell so these flowers don’t need to have a strong scent. Unlike bees, birds are not sensitive to ultra-violet light so flowers must be brightly coloured to attract them.

Humming-birds drink nectar from some flowers.

Some flowers need humming-birds to carry pollen to help them make seeds. Humming-birds also need flowers. They need the sugary nectar in these flowers for energy so that they can beat their wings up to 80 times a second!

Some bats and small animals like to drink nectar.

This tiny honey possum has a long snout and tongue for lapping up nectar from eucalyptus flowers. Its tongue can extend two centimeters from its body even though honey possums are only half the size of a mouse. Pollen rubs off onto the possum’s snout and is carried from one flower to another in this way.

Some flowers have brightly coloured petals. When bees and other insects see these bright colours they go to the flower to search for nectar. Other flowers have strong scents so that insects will go to them.

This bee saw the petals and is looking for nectar.

Insects see differently from humans. Some colours that look dull to us can attract insects to flowers when they are searching for nectar. Some rare flowers are very brightly coloured and have unusual shapes to attract insects who might otherwise ignore them.

Some flowers have strong scents to bring insects to them.

The Buddleia bush smells so sweet and attracts so many butterflies that it is called the ‘butterfly bush’. It is the nectar in the flower that smells sweet. Some flowers, such as the Rafflesia, smell of rotting meat, which attracts flies to them.

An evening primrose looks different to a bee than it does to us.

Bees can see ultra-violet light so they can see flower markings that are invisible to us. The flower markings point towards the nectar, stamens and carpels in the middle of the flower. Some flowers, such as this evening primrose, even advertise a landing platform for bees. This way, plants make sure that plenty of insects visit them.

To make a seed, pollen has to go from the male part of one flower to the female part of another flower. Many flowers have help from insects to move the pollen. Some plants use the wind, birds and other animals to carry pollen.

If a bee goes into this flower, pollen may rub off onto its legs.

When an insect enters a flower, it rubs against the male stamens as it tries to find nectar to feed on. Sticky pollen attaches itself to the insect’s back and legs. The insect then flies to another flower. Some insects are furry to make sure that even more pollen sticks to them.

The bee carries the pollen to the next flower.

Pollination is when a pollen grain lands on the carpel of a flower. Plants that use the wind to transfer pollen must produce thousands of pollen grains. This way, at least some of them reach a carpel.

Pollen joins with an egg to make a seed.

When a pollen grain lands on the sticky carpel, it grows a tube down towards   the female egg. When they join they begin to produce a seed and seed’s casing. This process is called fertilization.