![Water Lily Water Lily](/sites/default/files/styles/resource_card_image_360x300_/public/waterlily.jpg?itok=nnvmuAjZ)
Flowers: Cup Shape
Picture Collections
8 images of some flowerheads such as roses and water lilies whose outer petals are longer than the petals in the centre of the flower
![Iris Iris](/sites/default/files/styles/resource_card_image_360x300_/public/blueiris.jpg?itok=dvud8S14)
Flowers: Irregular Shape
Picture Collections
3 images of some asymmetrical flowerheads such as an iris and an Orchis Sima or Monkey Orchid
![Sunflower Sunflower](/sites/default/files/styles/resource_card_image_360x300_/public/sunflowers.jpg?itok=pmiRVO51)
Flowers: Radial Shape
Picture Collections
7 images of some symmetrical flowerheads such as asters and sunflowers whose petals radiate from the centre of the flower
![Petunias Petunias](/sites/default/files/styles/resource_card_image_360x300_/public/petunias.jpg?itok=yMPRRNyK)
Flowers: Trumpet Shape
Picture Collections
5 images of some flowerheads such as petunias and lilies that start as a narrow base and widen to an open shape
![bees on frame held by beekeeper](/sites/default/files/styles/resource_card_image_360x300_/public/2019-11/Bees_at_work.jpg?itok=eCBFpn4d)
How are the World's Bee Populations Doing?
STEM Explained
Bees are important for agriculture. But bee populations face threats. This resource looks at Colony Collapse Disorder, herbicides & pesticides, and more.
![heavy metal band](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/Heavy_metal_band_0.jpg?itok=-Zc4rYXH)
A Taste of Heavy Metal
STEM Explained
Heavy metal is a term for some toxic chemical elements. They can cause problems like bioaccumulation, but are useful in nuclear medicine and medical imaging.