Unit C: Cycling of Matter in Living Systems

It took several scientists building on each other’s discoveries to come up with Cell Theory - one of the cornerstones of biology.

Learn how chemistry and genetics makes redheads stand out from the crowd.

Learn about pollination and other forms of sexual reproduction in plants. And did you know that plants can also reproduce asexually?

Plants need to exchange gases and water with their environment as part of photosynthesis. Some plant cells have evolved specifically for this purpose.

Mitosis is an important part of cell division that helps organisms grow and repair themselves.

When you cut your finger, your immune system kicks in to protect you from pathogens.

Astronauts can experience bone loss in space. To understand why, you need to know a bit about how bones are formed and maintained in your body.

Do an experiment with celery to learn about the structures that help plants take up water.

How do plants use scents? Learn how some plants use chemical signals to send messages to animals or other plants.

When the cells of Henrietta Lacks were collected by medical researchers after her death in 1951, it changed the future of medicine.

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

Green walls use plant processes to improve air quality in buildings.