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90 Nature

NON FLOWERING PLANTS

Mosses, ferns, and their relatives are plants that do not

produce flowers but reproduce by means of. SPORES.

Most live in shady or damp habitats.. CONIFERS are

non-flowering plants that reproduce by making seeds.

HOW DOES MOSS LIVE WITHOUT ROOTS?

Most mosses grow in short clumps or cushions. They

do not have true roots, but short, slender growths,

called rhizoids. Root-like rhizoids anchor moss to soil,

rock, or bark, but do not draw up water.

Instead, leaves absorb moisture in the air.

HOW DO FERNS GROW?

The stem, or rhizome, of a fern grows horizontally

through the soil. Tiny curled-up fronds (leaves) grow

from small buds on the rhizome. The buds unroll and

the frond expands. The fronds of some ferns grow

6 m (20 ft) long – others reach only 13 mm (½ in).

WHY IS SPORE DISPERSAL IMPORTANT?

Many non-flowering plants rely on wind to carry

their reproductive spores as far away as possible.

This reduces competition with the parent plant for

light, water, and important nutrients. If a spore lands

in a damp place, it germinates (sprouts) and grows

into a new plant.

1 MOSS REPRODUCTION

The leafy tips of mosses produce

male and female sex cells. Male

sex cells swim through water

on the surface of the plant to

reach and fertilize female cells.

Fertilization produces a stalked

sporophyte, or spore capsule, that

scatters spores into the air.

4 LIVERWORT

This plant is closely related to

mosses, and is found only in

moist habitats. It grows on

soil, trees, and wet

rocks. The leaves of

some species have a

waxy coating to

reduce water loss.

TREE FERN 3

Dicksonia antarctica is a large

tree fern that grows on cool,

shady forest floors in Australia.

Tree ferns have a large, fibrous

trunk, topped with a crown of

fronds (leaves). This species can

grow 1–3 m (3–10 ft) tall.

Sporophyte

releases spores

that grow into

a new moss

Tree fern fronds

can grow 1.5–2.5 m

(5–8 ft) long

Sporangium

Sorus

Young bud unfurls

into a frond, or

branched leaf

SPORES

Non-flowering plants reproduce by

releasing large numbers of tiny spores.

These minute organisms consist of one

or a few cells inside a tough coat.

CLASSIFICATION OF NON-FLOWERING PLANTS

There are 11 main divisions of

non-flowering plants:

• Liverworts • Mosses
  • Hornworts • Whisk ferns
  • Clubmosses • Horsetails

• Ferns • Conifers • Cycads

• Ginkgo • Gnetophytes.

The last four form a group

called gymnosperms – they

produce seeds instead of spores.

FERN SPORES 3

Fern spores develop in protective caps called sori (singular

sorus). Sori are attached to the underside of fronds. Large

ferns make and release millions of spores each year.

INSIDE A SORUS 3

Each sorus contains

a cluster of spore-

producing sporangia.

In dry conditions,

sporangia open and

scatter their spores.

Non-flowering Plants