Introduction: (Initial Observation)
Looking inside each fruit, you see different sections and different material. Each of these material can be identified by it’s color, texture or taste. Some parts are delicious and juicy. Some other parts are hard and may have an unpleasant taste.
These material may also contain different nutrients.
This project is an opportunity to learn about different parts of fruits and learn their names and their properties.
Adult supervision and help is required for cutting fruits and making a display.
Find out about different fruits. Read books, magazines or ask others who might know in order to learn about different parts of each fruit. Keep track of where you got your information from.
Collect samples of apple, orange, apricot, blackberry, blueberry, cherry, grape, pear, peach, plum, raspberry, strawberry.
For each fruit write down the size, weight, color, texture and odor.
Then cut each fruit and look inside. What color is inside the fruit? Do you see any seeds in this fruit? how many seeds? What is the shape, size and color of the seeds?
What is a fruit?
When you think of a fruit, you probably think of something sweet like an apple or an orange. However, to a botanist a “fruit” is the part of a plant that holds the seeds. Therefore, a cucumber is a fruit too, and so is a squash or a walnut.
botanist is a plants specialist or someone who studies plants.
- an apple is a fruit.
- an apple grows on trees.
- a group of apples is an orchard.
- some apples are sweet; others are sour.
- apples can be large or small.
- seeds from an apple can grow into a tree.
- There are over 7,500 known varieties of apples in the world. About 2,500 varieties are grown here in the United States.
- Nearly 100 varieties are grown commercially in the U.S., but a total of fifteen popular varieties accounts for over 90 percent of production (listed in order of 1991 production):
- Fuji and Gala apples are among the newest and fastest growing varieties to gain foothold in the U.S. market.
- The Granny Smith variety is expected to replace McIntosh in 1992 and the #3 most popular apple.
- Apple growers produce 39 pounds of apples per person in the U.S. in 1991. That’s over 100 apples per person for one year alone.
According to the familiar saying, eating one of these apples a day will keep you healthy. Apples are definitely nourishing as well as tasty. This fruit contains a natural sugar that makes a great snack food because it supplies the body with a quick energy source while being low in calories-an average apple contains only about eight calories. Apples are low in sodium, high in fiber, and contain no cholesterol-all important for maintaining a healthy body. As a bonus, the crisp juicy texture of the apple helps to message gums and clean teeth.
Different kinds of apples are different in colors, shapes and sizes. Their flesh is also different colors and textures and these vary in how sweet they taste.
Apples are another example of a food most people like. Maybe that’s because there are so many kinds of apples.
No doubt you have heard of Johnny Apple seed. He was a bit of an apple fanatic. His real name was John Chapman, but not too many people would recognize him by that name.
Three main layers of fruits, from outside to inside are Exocarp, Mesocarp and Endocarp.
Very young students do not need to memorize the names Exocarp, Mesocarp and Endocarp. They can simply call them skin, flesh and core.
In citrus fruit, the exocarp, colored yellow, orange, or green, is called the flavedo. Located in the exocarp are spherical oil glands containing, e.g., lemon oil. The white portion of the fruit wall is the mesocarp and is called albedo. The locule is a chamber in which the juice sacks and seeds, are found.
In the citrus fruit, the layer of endocarp lining the outside of the locule grow as hairs that project into the locule. Cells of these hairs store water, organic acids, and sugars, and each hair therefore becomes a juice sacs. These juice sacs eventually fill the locule. The locule, when mature, becomes the section of a tangerine containing the juice sacs (hairs) within.
What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement.
The purpose of this project is to identify and display the internal organs (or parts) of any specific fruit of your choice (Orange, Apple, …).
If you choose to study more than one fruit, you may also compare them based on their properties such as average weight, number of seeds, and diameter of mesocarp.
If you want to do this project as an experimental project (investigatory project), then you may select any of the following questions for your project:
How do fruits vary in their number of seeds?
Do all apples have the same number of seeds?
When you think you know what variables may be involved, think about ways to change one at a time. If you change more than one at a time, you will not know what variable is causing your observation. Sometimes variables are linked and work together to cause something. At first, try to choose variables that you think act independently of each other.
If you decide to compare different fruits for their number of seeds, this is how you can define the variables.
Independent variable (also known as manipulated variable) is the type of fruit. Possible values are apple, orange, tomato, peach, pear.
Dependent variable (also known as responding variable) is the number of seeds.
If you are comparing fruits for any other properties, you may substitute the number of seeds with any other property of your choice.
Based on your gathered information, make an educated guess about what types of things affect the system you are working with. Identifying variables is necessary before you can make a hypothesis.
As a display project you will not need a hypothesis.
If you want to do this project as an experimental project (investigatory project), then you may select any of the following hypotheses for your project:
1. Among apple, orange, tomato, peach, pear, tomato has the highest number of seeds.
2. All apples have the same number of seeds
Design an experiment to see and display different parts of a fruit. Make a step-by-step list of what you will do for your activity.
Activity 1: Parts of an Orange
Use a knife to cut an orange. Cut the orange equatorial (like when you want to make orange juice. Also known as transverse).
The outermost layer of the fruit wall is called Exocarp. In orange, yellow material in the outer layer of skin are flavedo (yellowness) and oil sacs.
The fleshy layer of a fruit wall is called Mesocarp. In orange, these are the white material in the inner layer of skin, also known as Albedo or Pith.
Inside orange you see segments or compartments known as locule. These segments are separated from each other by their membrane also called Endocarp.
Inside locules is filled with juice sacks and a few seeds.
Make a large drawing of an orange equatorial cross section and label different parts of an orange in your drawing. Use this drawing and a real orange in your display.
The picture below shows an equatorial cross section of an orange.
Some oranges like the one shown in the following picture, are genetically modified to have no seeds or very small seeds.
Activity 2: Parts of an Apple
Prepare a chart which shows the parts of an apple. Print the name of each apple part on separate cards.
Repeat the procedures in the activity one for an apple.
With Apple, it is best if you cut it longitudinal as shown in the right picture.
An equatorial cross section can also be helpful.
In apple, Exocarp is the skin, Mesocarp is the white flesh that we eat. Endocarp is the hard membrane inside the core.
Unlike orange, in many other fruits such as apple, peach and watermelon, mesocarp is the delicious part of fruit that we eat.
Experiment 3: How do fruits vary in their number of seeds?
- Collect 2 samples of each fruits you want to compare for their number of seeds.
- Carefully cut each fruit and count the number of seeds.
- Record your results in a table as shown below.
- Take average of your results and enter them on your results table.
|Fruit Name||Seeds in 1st sample||Seeds in 2nd sample||Average number of seeds|
Make a graph:
You can make a bar graph to visually display your results. Make one vertical bar for each fruit you test. Write the name of fruits over or under the bars they represent. The height of each bar will show the number of seeds for that fruit.
Materials and Equipment:
List of material can be extracted from the Activity/ Experiment section.
Results of Experiment (Observation):
Experiments are often done in series. A series of experiments can be done by changing one variable a different amount each time. A series of experiments is made up of separate experimental “runs.” During each run you make a measurement of how much the variable affected the system under study. For each run, a different amount of change in the variable is used. This produces a different amount of response in the system. You measure this response, or record data, in a table for this purpose. This is considered “raw data” since it has not been processed or interpreted yet. When raw data gets processed mathematically, for example, it becomes results.
Draw an equatorial cross section and a longitudinal cross-section of orange or any other fruit as a part of your display.
Make a results table:
If you have compared different fruits for their number of seeds, you may make a results table like this:
|Fruit name||Average number of seeds||Average weight|
To calculate the average number of seeds, count the seeds of three different samples of each fruit and take an average.
Make a graph:
You can also display your results in the form of a bar graph. Make one vertical bar for each fruit. Write the name of each bar (the name of fruit) under the bar. The height of the bar will represent the average number of seeds in that fruit.
No calculations are required for this project.
Summary of Results:
Summarize what happened. This can be in the form of a table of processed numerical data, or graphs. It could also be a written statement of what occurred during experiments.
It is from calculations using recorded data that tables and graphs are made. Studying tables and graphs, we can see trends that tell us how different variables cause our observations. Based on these trends, we can draw conclusions about the system under study. These conclusions help us confirm or deny our original hypothesis. Often, mathematical equations can be made from graphs. These equations allow us to predict how a change will affect the system without the need to do additional experiments. Advanced levels of experimental science rely heavily on graphical and mathematical analysis of data. At this level, science becomes even more interesting and powerful.
Using the trends in your experimental data and your experimental observations, try to answer your original questions. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did.
Related Questions & Answers:
What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that need to be tested.
- What is an apple?
- Can you name the parts of an apple?
- Where do apples grow?
- What color are apples?
- What size is an apple?
- What are apples use for?
Make up similar questions for any other fruit that you want to study.
If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.
If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.
This section is not needed for display projects.
List of References