Y CL REPRODUCT HRT “fun”damentals - Arkansas Children’sY CL REPRODUCT HRT ACHRI/DGS/KFK/072412/V1 DRAFT COPY • ©2012 Delta Garden Study. Frameworks sCIeNCe NS 1.6.5 Communicate

“fun”damentalsanalysis of a poultry egg

Life CyCLes, RepRoduCtion & HeRedity

ACHRI/DGS/KFK/072412/V1 DRAFT COPY • ©2012 Delta Garden Study.

Frameworks

sCIeNCeNS 1.6.5 Communicate results and conclusions from scientific inquiry. LS 3.7.5 Dissect a poultry egg to analyze its structure (e.g., paper, plastic or clay models, virtual dissection or specimen dissection).NS 1.8.6 Formulate inferences based on scientific data.

LaNGUaGe arTsW 5.6.10 Write across the curriculum.W 5.7.10 Write across the curriculum.W 5.8.10 Write across the curriculum.

s objeCTIvesThe students will learn:

objeCTIve #1 To describe the basic structure of a chicken egg.

objeCTIve #2 To dissect, examine and label the structural parts of raw and boiled eggs.

objeCTIve #3 To differentiate between fertilized and unfertilized eggs.

objeCTIve #4 To appropriately use verbal speaking skills in class discussion with the teacher and Garden Program Specialist


Page 2 LIFe CYCLeS, RePRODuCTION & HeReDITY • “Fun”damentals: Teachers’ Guide

Chick

ens a

re good for the garden because they help control

wee

ds a

nd in

sects,

fertilize the soil and provide eggs and m

eat.

overvIewA chicken egg contains seven major parts: an outer shell, membranes, yolk, albumen, germ spot or germinal disk, chalaza and air cell. Only healthy, fertilized eggs will hatch.

GardeN aCTIvITIes▲s Dissecting raw and boiled eggs

▲s Plant, harvest and work in the garden following the Garden Guide

▲s Recipes and Taste tests as time permits (refer to Delta Garden Study Recipe Book)


LIFe CYCLeS, RePRODuCTION & HeReDITY • “Fun”damentals: Teachers’ Guide Page 3

TIps For THe CLassroomPre-lesson preparation:

1. Determine how the “Basic Structure of a Chicken egg” visual will be used and prepare appropriately.

2. Check with Garden Program Specialist to determine availability of eggs for dissection activity.

3. Inquire about egg allergies among students.

LessoN oUTLINe

activities estimated duration actual duration

in theclassroom

▲s Offer the icebreaker 5 minutes

in the garden ▲s Dissect eggs and discuss structure 10 minutes▲s Compare raw and boiled eggs 10 minutes

▲s As practical, instruct students to clean chicken coop and compost the manure

10 minutes

▲s Pick and taste produce as available 5 minutes

back in theclassroom

▲s Hand out Student Workbooks, review, and assign “Take it Home Activity” as homework

5 minutes

TIps For THe GardeNPre-lesson preparation:

1. Collect and prepare enough eggs for dissection activity. Hard-boil enough eggs for students to dissect.

2. Check with teachers to determine egg dissection procedure (dissect eggs in groups, individually, etc.).

3. Prepare a brief garden work activity for students tending chickens (cleaning coop, feeding, collecting eggs, etc.)

classroommaterials needed

▲s Student Workbooks

▲s Keep the “Basic Structure of a Chicken egg” visual handy during class

gardenmaterials needed

▲s Fresh and hardboiled eggs

▲s Materials for egg dissection (see Supporting Information for Teachers)

▲s Garden tools



LessoN pLaN

I. Start in the classrooma. Icebreaker

Ask students “what are the common parts of the egg, visible when eaten?”

ANSWeR: The yellow part you can see when the egg is fried, (yolk) and the egg white (albumin).

II. Take class to the garden▲s Displaying the Visual page as visual aid, identify the structure of

a poultry egg. Summarize fertilization process and distinguish between fertilized and unfertilized egg.

meeTs objeCTIves #1–2

▲s Dissect and examine the raw and boiled eggs as described on the “Supporting Information for Teachers” page.

meeTs objeCTIves #1–2

▲s Demonstrate how to differentiate raw from boiled eggs. meeTs objeCTIve #3▲s Perform any pertinent garden tasks.

▲s Instruct students to pick and taste available vegetables. Ask for feedback. Ask students to describe which ones they recognize and which ones they eat at home.

meeTs objeCTIve #4

III. Take class back to classroom▲s Hand out the Student Workbook as reference material and class

assignment. Review take it home activities and encourage students to do them.

meeTs objeCTIve #4



sUpporTING INFormaTIoN For TeaCHers

baCkGroUNd

Dissecting and examining raw and boiled eggs allows students to develop their observation skills, and contrast and compare their results. They will also learn about the nutritional value of eggs.

Chickens are a wonderful addition to the garden for several reasons; the first reason is that they help to control insects and pests. Chickens eat bugs and insects that may be harmful to the plants in the garden. Chicken manure is also a great addition to compost piles, and its chemical makeup makes great fertilizer.

materials needed

▲s One raw and one boiled egg per student or student pair/group, depending on availability of eggs.

▲s Paper towels, paper plates

▲s Ruler, kitchen scale

▲s Pen and paper for each student or Student Workbook

▲s Flashlights

▲s Sturdy plastic bowls

procedure

1. Prior to the lesson, determine if any students are allergic to eggs. Those students should only observe, but not handle any eggs. Also prepare some hardboiled eggs.

2. In the classroom/garden, advise students that absolutely no eating of raw or boiled eggs is allowed.

3. As practical, instruct students to collect and wash eggs from the garden and chicken coop. enlist Garden Program Specialist’s assistance as necessary.

4. Summarize how fertilization in chickens occurs; this topic is covered in more detail in LS 2.6.4

5. Hand out one raw egg to each group.

6. Start by discussing the structure of the egg. Point out the air cell. Instruct the students to hold the eggs in front of a strong flashlight

and slowly move them from side to side. They should be able to see the air cell. The larger the cell, the older the egg. As available, compare and contrast sizes of different air cells.

7. Instruct the students to break open and empty the eggs on the paper plate. Hand out paper towels for wiping hands and spills.

8. Point out and discuss the individual parts:▲s Shell: It’s actually porous, although the

holes are too small for the human eye to see.

▲s Membranes: To show the outer membrane, loosen it from the inside of the shell; it should lift up in sections. To show the inner membrane, point out the thin layer holding the yolk together.

▲s Yolk: The intensity of the color depends on the mix of chicken feed. Instruct students to describe the color of the yolk. explain that the yolk is rich in Vitamin A, B-Vitamins, especially riboflavin, and iron. These nutrients are important for the human diet as they support healthy vision, a healthy immune system and healthy blood cells. The yolk also has a membrane called the yolk membrane.

▲s Germ spot or germinal disk: It is a tiny, often white spot visible on the yolk. If fertilized, this spot is the nucleus that grows into a baby bird. This spot starts as the zygote and turns into an embryo.

▲s Albumen (also spelled albumin): use a piece of shell or a spoon to lift it up. Some egg white is watery and thin; some is a little thicker and jelly-like. The thicker albumen is a major source of protein, important for growth and overall good health.

▲s Chalaza, or chalazae: Not to be confused with sperm, although Internet inquiries abound! This is simply more albumen that has thickened and developed into a type of rope to anchor the yolk to both sides of the shell. When cooking with eggs, some cooks prefer to discard the chalaza, although it is perfectly safe to eat.

9. Hand out the boiled eggs and instruct the students to break them open. Compare and contrast their interior structure to that of the raw eggs.



soUrCes

The day an egg solved the mystery of the Cell, arizona Grown specialty Crop Lesson planhttp://ag.arizona.edu/agliteracy/pdf/lessons/day_egg.pdf

jefferson County (Tenn.) schoolshttp://jc-schools.net/dynamic/science/lessons/eggresearch.pdf

Make Way for DucklingsLisa DiCioccio, http://lisadicioccio.com/Dduckling.htm

egg and embryo development, the Formation of an egghttp://www.enchantedlearning.com/subjects/birds/info/chicken/egg.shtml

How to Cook eggshttp://whatscookingamerica.net/eggs.htm

How to Tell if an egg is raw or Hard-boiledhttp://www.wikihow.com/Tell-If-eggs-Are-Raw-or-Hard-Boiled

How are Chicken eggs Fertilizedhttp://www.buzzle.com/articles/how-are-chicken-eggs-fertilized.html

Life Cycle of a Chickenhttp://www.hometrainingtools.com/life-cycle-of-a-chicken/a/1482/

10. Instruct students to carefully wash their hands.

11. Time permitting, demonstrate and discuss how to investigate the freshness of raw eggs and how to differentiate raw from boiled eggs:

How To TesT IF aN eGG Is FresH

Instruct the students to fill a plastic bowl with water and carefully lower a raw egg into the water. Observe and discuss what happens to the egg. Will it immediately sink to the bottom? Does it float? Does it come to the surface?

Fresh eggs will immediately sink to the bottom and lie on their sides because their air cells are quite small. The older the egg, the larger the air cell. As the eggs age and air enters the shells, the eggs will begin to float, with the larger end pointing to the surface. They are still considered safe for human consumption. eggs that fully float and even rise to the surface should be discarded as too old and possibly bad.

The air cell normally gets larger as a chick is developing inside the egg. As the chick arranges

its head toward the air cell it soon breaks through the inner membrane and can begin to breathe air. Later, when the chick breaks the shell, its lungs will begin to function more fully and breathe outside air.

How To dIFFereNTIaTe raw eGGs From boILed eGGs

Randomly hand out raw and boiled eggs to the students without telling them which ones are which. Instruct students to place each egg gently on the surface of table/desk or countertop. Instruct them to gently spin each and then place and lift a finger on the egg to stop the spinning. Observe and discuss what happens. Does the spinning action continue?

An egg that continues to wobble is raw. That’s because the liquid interior still has momentum and continues to move within the shell. In contrast, a hard-boiled egg has a solid interior and will remain stationary when stopped.



Bas

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Egg

“fun”damentalsanalysis of a poultry egg

Life CyCLes, RepRoduCtion & HeRedity


study guide for studentsHow do you like your eggs? You’ve probably sampled eggs many times—scrambled, over-easy, poached—but have you ever really looked at them?

An egg can be a nutritious, tasty meal or it can turn into a baby bird, if fertilized by a male chicken, (rooster). either way, it starts out as a yolk inside the hen’s ovary in a process called ovulation. It is released into the oviduct (a tube-like part of the hen’s productive system) for a day-long journey where it develops some more and might or might not be fertilized by sperm from the rooster. Just before the egg is laid, a shell is deposited around it.

Let’s examine:1. Shell: The shell is the hard, outer part. It is made of calcium carbonate or limestone. Although

it feels solid, it is actually covered with almost 10 million pores, which allow water and gases to pass through. If the egg is fertilized, the shell protects the baby bird and serves as a source of calcium for its growing bones. The shell can be brown, white or shades of blue or green, depending on the breed of chicken.

2. Outer and inner membranes: The outer membrane is just inside the shell and protects against bacteria. The inner membrane is a thin sac that contains the albumen or egg white.

3. Yolk: This is the yellow (sometimes orange) center of the egg where the embryo forms, if fertilization occurred. It is the food source for the bird and represents 1/3 of the liquid weight of the egg. It is rich in vitamins, minerals, protein and some fat, which is why it makes a good snack for people, too.

4. Yolk Membrane: This membrane forms a clear sac that surrounds the yolk. It keeps the yolk together while the chick develops in the egg.

5. Germ spot or germinal disk: A tiny spot on the yolk. If fertilized, this spot is the nucleus or zygote that grows into a baby bird.

6. Albumen (also spelled albumin): This is the thin, watery, whitish layer that surrounds the yolk. Most people simply call it egg white. It is very nutritious with riboflavin and half of the egg’s protein.

7. Chalaza [kuh-ley-zuh], also spelled chalazae [kuh-ley-zee]: A thick strand of albumen that looks like a twisted rope. It anchors the yolk to prevent it from being tossed against the inside of the shell. There is a chalaza rope on the top and bottom of the egg, letting the yolk

Continued next page


Page 2 LIFe CYCLeS, RePRODuCTION & HeReDITY • “Fun”damentals: Study Guide

swing as if it were in a hammock. The more prominent the chalaza, the fresher the egg.

8. Air cell: This pocket of air forms at the large end as the egg cools. It is located between the outer and inner membranes and allows the chick to breathe while it is trying to hatch. A healthy chicken’s internal temperature is about 107 degrees F, so a freshly laid egg is quite warm. The older the egg, the larger the air cell. (Once you crack open an egg, you won’t see the air cell anymore. Why not?)

Only healthy, fertilized eggs can grow into baby birds. They need to be incubated for about 3 weeks before a chick pecks its way through the shell and is hatched. Animals, such as birds, most reptiles and fish, are oviparous, that is, they lay eggs instead of having a live birth, such as mammals, including humans. The opposite of oviparous is viviparous. The eggs you buy at the supermarket or farmer’s market are not fertilized. Could you find a fertilized egg at the school garden? It depends on whether or not a rooster is around. . .

Chickens are a wonderful addition to the garden for several reasons; the first reason is that they help to control insects and pests. Chickens eat bugs and insects that may be harmful to the plants in the garden. Chicken manure is also a great addition to compost piles, and its chemical makeup makes great fertilizer.

chalaza one of two spiral bands of tissue in an egg that connect the yolk to the lining membrane at either end of the shell. incubate to hatch (eggs), as by sitting upon them or by artificial heat.oviparous producing eggs that mature and hatch after being expelled from the body, as birds, most reptiles and fishes, and the monotremes.viviparous giving birth to living young that develop within the mother’s body rather than hatching from eggs.shell the outer part of the egg that is hard. outer membrane the layer just inside the shell that protects it against bacteria.inner membrane the clear sac that surrounds the albumen or egg whiteyolk the yellow center of the egg where the embryo forms.yolk membrane the clear sac that surrounds the yolkembryo the chicken in the early stages of development inside the egg. germ spot a tiny spot on the yolk, if fertilized, this spot will grow into the baby bird.albumen thin, watery, whitish layer that surrounds the yolk. air cell the pocket of air that forms at the large end of the egg as it cools, it allows the chick to breathe while it is trying to hatch.

Basic Structure of a Chicken Egg


“fun”damentalsLife CyCLes, RepRoduCtion & HeRedity

Aclass

assignment

LS 2.6.4 Model and explain the function of animal organs.

1. How does an egg protect and feed the developing chick?

The ______________________ protects it.

The ______________________ provides food.

The ______________________ allows it to breathe.

2. animals that lay eggs are called what?

a. Carnivorous

b. oviparous

c. porous

3. The skin-like material that surrounds the egg yolk is called __________ .

a. Incubation period

b. membrane

c. shell

Take it HomeWhat are some of your favorite dishes made with eggs?

Make one of those recipes tonight.



Aclass

assignment

answer key

1. How does an egg protect and feed the developing chick?The shell protects it.

The yolk provides food.

The air cell allows it to breathe.

2. animals that lay eggs are called what?b. Oviparous

3. The skin-like material that surrounds the egg yolk is called __________ .b. Membrane



Bclass

assignment


1. How does an egg protect and feed the developing chick?

The ______________________ protects it.

The ______________________ provides food.

The ______________________ allows it to breathe.

2. animals that lay eggs are called what?a. Carnivorousb. oviparousc. porous

3. The skin-like material that surrounds the egg yolk is called the _______ .a. Incubation periodb. membranec. shell

4. Label the parts of a chicken egg:





Bclass

assignment

answer key

1. How does an egg protect and feed the developing chick?The shell protects it.

The yolk provides food.

The air cell allows it to breathe.

2. animals that lay eggs are called what?b. Oviparous

3. The skin-like material that surrounds the egg yolk is called the _______ .b. Membrane

4. Label the parts of a chicken egg:



Cclass

assignment


1. sketch and label a cross section of a chicken egg.

2. describe why the air cell is important in an egg.





Cclass

assignment

answer key

1. sketch and label a cross section of a chicken egg.

2. describe why the air cell is important in an egg.Air cells form at the large end of the egg, which allows for the chicken to have some room to breathe while it is trying to hatch.

Documents

Y CL REPRODUCT HRT “fun”damentals - Arkansas Children’sY CL REPRODUCT HRT ACHRI/DGS/KFK/072412/V1 DRAFT COPY • ©2012 Delta Garden Study. Frameworks sCIeNCe NS 1.6.5 Communicate