Science 7
Unit 3
Living Things: Protista-Plantae
Name: ______________________________
Date: ______________ Period: __________
Seeds: Characteristics of Seed Plants
Seeds are structures that contain a young plant inside a protective covering. A seed has three important parts – an embryo,
stored food in a cotyledon, and a seed coat.
The young plant that develops from the zygote, or fertilized egg, is called the embryo and has the beginnings of roots
stems and leaves. Food is stored inside one or two seed leaves, or cotyledons. The outer covering of a seed is called the
seed coat.
There are three main types of seeds. Pine seeds, which come from cones, are from Gymnosperms. These are all evergreen
trees: pine, spruce, fir, redwood, etc. The others are from Angiosperms or flowering plants. In all three types it is possible
to see the beginnings of the baby plant.
The names Monocot and Dicot refer to the number of cotyledons in an angiosperm seed. The prefix mono- means one
and the seed has 1 cotyledon. The prefix di- means two and there are two cotyledons or two visible halves inside the seed
coat.
Germination is the early growth stage of the embryo. Germination begins when the seed absorbs water from the
environment, usually warmth and fresh air and uses its stored food to begin to grow. When germination begins, the roots
and stems first appear to break out of the seed coat. A young plant just starting to grow is called a seedling. Growth occurs
at the tips of the stems and roots (the apical meristem) and in specialized rings around the plant (the lateral meristem). The
tip of the stem where the growth is occurring is called the bud.
1. What is a seed? __________________________________________________________________
_______________________________________________________________________________
Match the definition to the vocabulary word.
_______ 2. embryo
a. flowering plant
_______ 3. cotyledon
b. a seed leaf that stores food
_______ 4. seed coat
c. fertilized egg
_______ 5. zygote
d. has only one cotyledon
_______ 6. gymnosperm
e. young plant that develops from the fertilized egg
_______ 7. angiosperm
f. evergreen plant that produces cones
_______ 8. monocot
g. a young plant starting to grow aboveground
_______ 9. dicot
h. has two cotyledons
_______ 10. germination
i. protective layer that keeps the seed from drying out
_______ 11. seedling
j. begins when conditions are right and the embryo
breaks free of the seed coat.