Big Idea: Cells are derived from cells.

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

3 images of some asymmetrical flowerheads such as an iris and an Orchis Sima or Monkey Orchid

7 images of some symmetrical flowerheads such as asters and sunflowers whose petals radiate from the centre of the flower

5 images of some flowerheads such as petunias and lilies that start as a narrow base and widen to an open shape

Bees are important for agriculture. But bee populations face threats. This resource looks at Colony Collapse Disorder, herbicides & pesticides, and more.

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.