NAME ________________________________________________
Flowering Plant Reproduction
"YOU MEAN IT'S A FRUIT, TOO” ?
INTRODUCTION
Flowering plants produce seeds after the flower has been fertilized.
These seeds are contained in the ovary, the female reproductive
organ. However, after fertilization, the ovary usually enlarges, ripens, and is called a
fruit. The fruit still contains the seeds. It may later fall from the plant, "rot" open and
release it's seeds to the ground. In this lab, we will observe some fruits and seeds.
1. A fruit is an enlarged ripened __________________________
2. Name three fruits which contain seeds:
____________________ ____________________ ____________________
PART I - THE BASIC STORY
A. I have drawn a single tomato flower in stage 1 below. A tomato flower
turns into a fruit (tomato) in a way typical of many flowering plants.
To understand this process, make a drawing of stages 2-4 in the spaces
provided. I have described what happens in each stage.
STAGE 1
Typical tomato flower
STAGE 3
Style withers and falls off
STAGE 2
Pollen fertilizes pistil
Stamens and petals wither and fall off
STAGE 4
Ovary ripens with mature seeds
B. Next, select a ripened tomato ovary from the lab table. Find where the
stem is/was attached. Are there any sepals still attached? __________
Find where the style withered away at the opposite end. Now, using a
razor blade, slice across the middle of the ovary and remove the top
half. (Note: This may already have been done by a previous lab group.)
3. How many compartments are there? ____________________
4. How many seeds can you see? _________________________
PART II - FRUITS AND MORE FRUITS
When we think of fruits, we think of apples, oranges, grapes, etc.. Those are all fruits,
but so are other "vegetables". To a biologist, a fruit is a ripened ovary from a
flowering plant. So not only are watermelon and pineapples fruits, but so are
pumpkins and ears of corn. They are all ripened ovaries containing seeds.
5. A ripened ovary is called a _____________________________
6. The ovary is the female reproductive organ of a _____________________
Move to the FRUIT DEMONSTRATION TABLE. Most of the "veggies" assembled
here are fruits. Study each one to see if each has:
a. a stem or attachment point for the stem
b. sepals or attachment point for the sepals
c. an attachment point for the withered style
d. an outer ovary covering (fruit)
e. seeds
Compare each “veggie” to the typical fruit pictured below. Then fill in the chart on
the next page. Remember, some parts may have fallen off so all you will see is the
attachment point.
Typical Fruit Parts
(Cut open)
Stem
Sepals
Ovary covering
Withered style
Seeds
In the following chart, list each "veggie" by name and put a check mark in the space
for each fruit part it has.
__________________________________________________________________
"VEGGIE"
NAME
Stem
Sepals
Withered
Ovary
Seeds
Style
Covering
__________________________________________________________________
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7. List the "veggies" that are true fruits. To be a true fruit it has to have a check in
each box- _________________________________________________________
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8. List any "veggies" that are not fruits(missing at least one checkmark)____________
__________________________________________________________________
9. Which fruits have only one seed? ________________________