Plant Study Book

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SOL Study Book
Fourth Grade
Life Processes
Table of Contents
Page 1: Structures of Plants
Page 2: Pollination
Page 3: Processes of reproduction
Page 4: Seedless plants
Page 5: Photosynthesis
Page 6: Dormancy
Page 7: Practice Questions
Structures of Plants
For many typical green plants there are structures that
perform basic functions:
Roots anchor the plants and take water and nutrients from
the soil
A taproot sends a single large root into the soil
Fibrous roots spread out into the surrounding soil
Plant stems provide support and allow movement of water
and nutrients.
Veins are bundles of tubes that carry food and water in
stems and roots
Leaves are the main food making part of the plant. They
use energy from sunlight to make food from water and
carbon dioxide
Flowers make seeds that grow into new plants.
The sepals are small leaves that form the housing of the
developing flower.
Page 1
Pollination
A seed is an undeveloped plant with stored food sealed in
a protective covering.
Seeds can grow into small plants when given water and
light.
In most plants, seeds are made in flowers.
The male sex cells are found in pollen. Pollen is
produced by the anther which is part of the stamen.
The female sex cells, the eggs, are in the pistil.
Pollination can take place when pollen is carried form a
flower’s anther to its own pistil or another flower’s pistil.
Pollen can be carried from flower to flower by insects, the
wind or sometimes birds.
Page 2
Process of Reproduction
After pollination the next step in the formation of a seed
is fertilization.
After pollen reaches the pistil, a pollen tube starts to
grow. The pollen tube grows down the flower into the
ovary.
The ovary is a structure containing egg cells. It is the
ovary that grows to form a protective fruit.
The ovule is like the egg in animals and once fertilization
has taken place it will become the seed.
A seed develops from a fertilized egg cell into an embryo.
Inside each seed is an embryo and a food source. When
the time is right, the embryo uses the food to begin to
grow its first root, stem, and leaves.
Seeds disperse in different ways.
-Some plants scatter their own seeds. The protective,
fleshy fruits explode to shoot their seeds away from the
parent plant.
-Some seeds are carried by the wind or water.
- Some seeds are carried by animals
Page 3
Seedless plants
Some plants do not have flowers or produce seeds. Plants
such as mosses and ferns use spores.
A spore is a cell in a seedless plant. A spore can grow
into a new plant.
The moss plant has two separate stages in its life cycle.
In the first stage, it produces spores.
The moss spores grow into moss plants that have male
branches and female branches.
In the second stage, the male branches produce male sex
cells. The female branches make female sex cells.
One male and one female sex cell combine to make a
fertilized egg.
The fertilized egg grows into a thin stalk with a spore case
on top. When the spore case opens, the spores are
released.
Spores that land on damp ground may grow into new
moss plants, and the cycle begins again.
Page 4
Photosynthesis
Green plants produce their own food through the process
of photosynthesis
Green plants use chlorophyll to produce sugar (food)
using carbon dioxide, water, nutrients, and sunlight.
Leaves are the primary food producing parts of green
plants.
Oxygen and sugar are the products of photosynthesis.
The sugar is used as food for the plant and oxygen is
released into the air.
Page 5
Dormancy
Viable seeds that do not germinate are said to be dormant.
Dormancy can be regulated by the environment or by the
seed itself.
If a seed is not exposed to sufficient moisture, proper
temperature, oxygen, and for some species light, the seed
will not germinate.
Dormancy can help a plant to survive unfavorable
conditions, as in annual plants that pass the cold winter
season as dormant seeds.
Adaptations help the seeds survive in different types of
environments, increasing the chances that they’ll
germinate when conditions are right for growth.
 Some seeds require a period of cold temperatures
(winter) followed by warmth (spring) to germinate.
 Others have hard seed coats that soften up during
freeze and thaw cycles.
 Some seeds have chemicals in their coats that inhibit
germination until they are washed away by heavy
rains.
 Some seed coats require “scarring” before they will
germinate
Page 6
Practice Questions
Trees, wild flowers, and grasses are all
considered to be —
F vascular plants _
G nonvascular plants
H woody plants
J nonwoody plants
The part of a plant cell that gives the
cell its green color is the —
A nucleus
B cytoplasm
C vacuole
D chloroplast _
One way that mosses and ferns are
similar is they both —
A are flowering plants
B produce spores _
C grow in areas with little rainfall
D are dormant during the winter
Seeds can lie dormant for many years until —
A sunlight causes photosynthesis
B food webs are complete
C conditions are right for growth
D conduction of food occurs
Page 7
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