BIO 11 ANGIOSPERM and GYMNOSPERMS LAB
This lab is designed to help you differentiate between Gymnosperms and Angiosperms:
We will also look at two types of seeds called Monocots and Dicots
When identifying trees, you will need to determine whether they are conifers (cone producing evergreens)
or deciduous trees (seed producing, lose their leaves)
--Gymnosperms are a taxonomic class that includes plants whose seeds are not enclosed in an ovule (like a
pine cone). Gymnosperm means as "naked seed". This group is often referred to as softwoods.
Gymnosperms usually have needles that stay green throughout the year. Examples are pines, cedars,
spruces and firs. Some gymnosperms do drop their leaves - ginkgo, dawn redwood, and baldcypress, to
name a few.
--Angiosperms are a taxonomic class of plants in which the mature seed is surrounded by the ovule (think
of an apple). This group is often referred to as hardwoods. Angiosperms are trees have broad leaves that
usually change color and die every autumn. Oaks, maples and dogwoods are examples of deciduous trees.
Some angiosperms that hold their leaves include rhododendron, live oak, and sweetbay magnolia.
Most tree identification books define a shrub as a woody plant, growing to less than 5 meters in height (16
feet), with multiple stems.
A tree is a woody plant, growing to greater than 5 meters in height (16 feet), with a single dominant stem.
For this lab please collect as many examples of both Gymnosperms and Angiosperms as possible.
You will also need to look at Angiosperms in more detail and begin to understand the differnces between
monocots and dicots. I have attached a number of images to help you determine what kind of plant you are
looking at.
MONOCOTS and DICOTS
There are two different types of seeds: dicotyledons and monocotyledons. Dicotyledons are seeds with two
parts and monocotyldons have only one part. You can call theses seed types dicots and monocots for short.
An example of a dicot would be a bean seed. A bean seed that has been soaked in water has a soft outer
covering. This outer covering is the seed coat. Inside of the seed would be a tiny plant called the embryo.
The two large parts of the seed are called the cotyledons. The cotyledons are stored food that the young
plant will use while it is growing.
Monocots are seeds that have only one cotyledon, such as the corn seed. Monocots have a thicker seed coat
that does not slip off easily like the bean seed. The corn seed does not split open like the bean seed, it stays
in one piece. One cotyldeon surrounds the embryo and is called the endosperm.
Please Collect Examples of:
Cones:
Chose a variety of shapes and sizes. Look
for both male and female. First and
Second year Cones.
Seeds/Fruit: Look for berries or seeds found on grasses
or other Angiosperms
Stems:
Collect a variety of woody, green, and
vines.
Look for examples of primary and secondary growth.
New shoots: is there anything just breaking ground?
Look for examples of apical meristamic tissue