(Primary Science) What are spores?

Science textbooks often say ferns reproduce by spores, not seeds. But they don't explain what spores are. Even Lower Secondary Science will not tell you too. That's because it's difficult to explain in simple ways for your level. You don't need to know a lot about spores for your PSLE. Just read this for your interest so that you can distinguish seeds from spores.

Flowering plants reproduce from seeds...

Ferns reproduce from spores...

How is the seed formed? First, a flower needs to be pollinated. The next stage is fertilization. The male sex cell from pollen and female sex cell in the ovary join together. The fertilized egg then develops into a seed. The seed contains the baby plant. When conditions are right (water, air, warmth), germination occurs and the baby plant grows out.

In flowering plants,

fertilization occurs in the ovary and seeds develop...

seeds germinate and new plants grow out...

How about spores? Spores are formed from a kind of cell division. How do spores become the adult plant? Spores are scattered from underneath fronds. When conditions are right, germination occurs and the spore grows into a small heart-shaped structure. This small structure contains male and female parts. In wet conditions, the male sex cells swim to fertilize the egg. The fertilized egg then grows into an adult fern plant. 

(I know that it sounds very weird that that heart-shaped structure has both male and female parts. I found it strange too when I learned it. Anyway, the heart-shaped structure is called prothallium.)

In ferns,

spores germinate to form heart-shaped structures...

fertilization occurs in the heart-shaped structure...

Now that you have read about seeds and spores, try to come out with a table to distinguish between the two. Here is an example.

	Seed	Spore
(a) Where is it formed?	(i)	(ii)
(b) How is it formed?	(i)	(ii)
(c) How does it grow into an adult plant?	(i)	(ii)

Answers: (a)(i) The seed is formed inside the ovary of a flower. (a)(ii) The spore is formed underneath a frond. (b)(i) The seed is formed when the egg in the ovary fuses with the male gamete from the pollen. (b)(ii) The spore is formed through cell division in the adult plant. (c)(i) When seed germinates, the baby plant grows out of the seed. (d)(ii) The spore germinates into a heart-shaped structure. Fertilization occurs in the heart-shaped structure and a fern plant grows.