LESSON

1

How Animals Are Born

Look at the pictures below. Observe the mother dog and the puppies. Observe also the mother cat and the kittens. Compare the mother cat with her kittens.

How are they alike? How are they different?

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What animals lay eggs?

Animals are alike in many ways. They need food. They need air. They also need water. Animals like plants can also produce other animals like themselves. The way in which animals produce other animals like themselves is called reproduction. What are the ways by which animals reproduce? There are animals that lay eggs like the hens and the ducks. What do you think would come out from a hens egg? What could come out from a ducks egg?

A baby chick would come out from a hens egg. A baby duck would also come out from a ducks egg. And a baby bird would also come out from a birds egg.

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Some animals come from eggs. They start their life outside the bodies of their mothers. When the eggs hatch, the baby animals come out.

Chickens, ducks, turtles, snakes, lizards, and birds are examples of animals that hatch from eggs with shells. Give other animals that hatch from eggs with shells. Some animals come from eggs. They start their lives outside the bodies of their mothers. Do dogs and cats lay eggs?

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Look at these pictures of baby animals and their parents. Do baby dogs look like their mother dog? These baby dogs were born alive. They are called puppies.

Do baby cats look like their mother cat? These baby cats were born alive. They are called kittens.

Does the picture of the baby carabao look like the mother carabao? This baby carabao was born alive. It is called a carabao calf.

Look at the baby horse. Does he look like the mother horse? The baby horse was born alive. A baby horse is called pony.

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Some animals are born alive. They start their lives inside the bodies of their mothers. When baby animals are born they look like their parents. Some animals are born alive.

In this lesson you learned that there are animals that come from eggs and there are also animals that are born alive. Some animals that are born alive are the goat, monkey, rabbit, carabao, dog, and cat. Some animals or insects that come from eggs are butterfly, snake, bee, grasshopper, fish, chicken, and spider.

Self Test (Lesson 1)A. Below is a list of different kinds of animals. Opposite each number write born alive, if the animal is born alive and write comes from an egg, if the animal comes from an egg. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. butterfly cow carabao cat snake goat dog bee ant grasshopper

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B.

Classify the animals below into two groups. Write your answers in a table like the one below.

Animals That Are Born Alive

Animals That Come from Eggs

duck chicken

rabbit rat

pig horse

fish parrot

spider monkey

AFTER WRITING YOUR ANSWERS, RAISE YOUR HAND TO SHOW THAT YOU ARE READY FOR THE GROUP DISCUSSION.6

LESSON

2

How Some Animals Develop

There are animals that look like their mothers when they are born. Others do not. They change as they grow. In this lesson you will study how some animals grow and develop in different ways. How does a butterfly grow? Lets find out by doing this activity:

Do ThisActivity A a) Look for butterfly eggs from the leaves of some plants in the garden.

b)

Place the butterfly eggs in a wide-mouthed bottle and cover them with a wire screen.

When the butterfly eggs hatch, tiny animals come out.7

c)

Look for a caterpillar and place it also in a wide-mouthed bottle. Cover the bottle with a wire screen. Observe it each day. Look at it using a hand lens.

How does the caterpillar move? What does it eat? d) Record the changes that take place as the caterpillar grows. Record them in a table like the one below. Date Sept 15. Drawing Observations It crawls.

GO TO THE NEXT LESSON WHILE YOUR OBSERVATION IS GOING ON.8

Answer the following questions: 1. 2. 3. 4. 5. How many days did it take the caterpillar to become a pupa? How many days did it take the pupa to become an adult butterfly? Compare a caterpillar with a pupa. What makes the caterpillar move? Does the pupa move like a caterpillar? Study the adult butterfly. Why can it fly? Describe its parts.

AFTER WRITING YOUR ANSWERS, RAISE YOUR HAND TO SHOW THAT YOU ARE READY FOR THE GROUP DISCUSSION.

The butterfly undergoes several changes as it grows.

Compare the table you made for your observations with the drawing below:

Eggs

Adult

Larva

Pupa

The drawing above shows the Life Cycle of a Butterfly.

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You learned that a butterfly undergoes several changes as it grows. How about a mosquito, how does it grow?

Do This ActivityActivity B 1. 2. Look for some wrigglers (kitikiti) in places with stagnant water like jars and vases. Place the wrigglers in a bottle of water but do not cover the bottle.

3. 4. 5.

Observe how the wrigglers move. Do they jump or do they jerk? Why can they jerk? Notice that the wrigglers come to the surface of the water once in a while. Why? What is their position when they are near the surface of the water? Get one wriggler. Place it in a white piece of paper. Study it with a hand lens. Tell how its body looks. Describe its parts.

6. 7.

Observe the wrigglers for several days. Do you notice any changes in them? What happens to them? Keep a record of what you have observed. You may make one like this:

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Date Oct. 10

Drawing

Observations It jerks.

GO TO THE NEXT LESSON WHILE YOUR OBSERVATION IS GOING ON. Answer these questions: 1. 2. How long did it take the wriggler or larva to become a pupa? How long did it take the pupa to become an adult mosquito?

Compare what you have observed with the picture below and the information that follow.

Eggs

Adult

Larva

Pupa

The Life Cycle of a Mosquito

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Young mosquitoes are called wrigglers. Wrigglers come from mosquito eggs. After some time the wrigglers become adult mosquitoes. An adult mosquito bites people and animals. When a mosquito bites, it sucks the blood of the person through a long tube in its mouth called the proboscis. The drawing below shows how a mosquito bites a human skin:

A mosquito undergoes several changes as it grows and develops.

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How do flies grow? Look at the picture below. It shows the stages in the life cycle of a fly.

Egg

Adult

Larva

Pupa

There are four stages in the life cycle of a fly. The first stage is the egg. Eggs of most flies are long and white. The housefly lays eggs in the garbage and in ripe and rotting fruits. A few hours after these eggs have been laid, these eggs hatch into larvae. The larvae are called maggots. These maggots feed and grow on garbage. They also grow on foods where they are laid. A few days after, they drop their body covering and develop a new one. Each larva develops into pupa. Then the pupa becomes an adult fly. The fly starts as an egg. Then the egg hatches into a larva. The larva develops into a pupa and the pupa becomes an adult fly.

Do This ActivityActivity C 1. Look for some frogs eggs and place them in a bottle with water.

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2.

Watch the eggs until they hatch.

3.

Separate two tadpoles by placing them in another bottle with water.

4.

Record the dates when you notice changes in what you are observing. Make a table like the one below. Drawing 1. 2. 3. 4. 5. What I Saw The eggs hatched. The tadpoles appeared. The hind legs appeared. The front legs appeared. The tail disappeared. Date Nov. 5

Did you observe all these? GO TO THE NEXT LESSON WHILE DOING YOUR OBSERVATIONS.14

Answer the following questions: 1. 2. 3. 4. How many days did it take the tadpoles to grow the hind legs? How many days afterwards did the front legs appear? What happened to the tail as the frog grew? How is the shape of a tadpole similar to or different from the shape of an adult frog?

A frog undergoes several changes until it reaches the adult stage. The period from the egg stage to the adult is called the life cycle of a frog. The drawing below shows the life cycle of a frog:

Let us now study how a chick grows. Have you tried to open a fresh egg which has not been placed in an incubator? What do you find inside the shell? Find out.

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Do This ActivityActivity D Get a fresh chicken egg. Open it and place it in a saucer. Observe its contents. Do you see the yolk? Examine it with a hand lens. Do you notice the white spot in the yolk? Examine the white of the egg. Get a toothpick and stir it. Is it sticky? The drawing below shows whats inside an egg.

Compare it with the egg you have opened. What parts are the same? White Spot Shell (developing chick)

Air Space Membrane Twisted Parts in the White White Egg If you stir the white of an egg, you will notice that there are some twisted parts which are thicker. These thicker twisted parts of the white keep the yolk in place. They protect the developing chick from any disturbances.16

Outside the white of the egg is the shell. How does a chick grow and develop?

Do This ActivityActivity E Get a two-day old incubated egg. Open it. Compare its content with that of a fresh egg. What changes do you observe? Then get a five-day old incubated egg. Open it. How is its content different from that of a two-day old egg? Continue your observations using a chart. GO TO THE NEXT LESSON OR MODULE WHILE YOUR OBSERVATION IS GOING ON. Your chart may look like the one below. Copy the chart in your notebook. Date 2 days 5 days 10 days 15 days 20 days 21 days Drawing Observations

The chick hatches from an egg. It hatches after 21 days. The chick breaks its shell and comes out like a little chicken. As the chick grows and develops inside the shell, it gets its food from the yolk. After 20 days, all the food is used up. Then, the chick is ready to live outside of the shell.17

Look at the pictures below. Compare them with your observations. This is the Life Cycle of a Chick.

2 days 5 days

21 days

20 days

10 days

15 days A chick passes through different stages of development. It starts as an egg and it comes out of the shell as a chick. Here is another activity.

Do ThisActivity F Look for some cockroach eggs in some drawers, bookcases, and closets. These eggs may be attached to cardboards, sheets of paper, or books that are in dark places. What do the eggs look like?18

Place the eggs in a glass jar. Put some bread crumbs in the jar. Observe what will happen to these eggs. Make a record of your observations to know the life cycle of a cockroach. You can make a table like the one below for your observations. Date Drawing Observations

GO TO THE NEXT LESSON OR MODULE WHILE YOUR OBSERVATION IS GOING ON.19

Look at the drawing below. Compare your observations with the drawings and information that follow:

A cockroach passes through three stages of development. They are: the egg, the nymph, and the adult. You learned that some animals hatch from eggs. Examples of these animals are the butterflies, the mosquitoes, the flies, the frogs, the chicks, and the cockroaches. These animals change as they grow and develop. In what places do these animals develop? Where can you find their eggs? Make a table like the one below. Provide the information that is needed. Eggs Mosquito eggs Cockroach eggs Fly eggs Butterfly eggs Where They Were Found

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Study the pictures below. Then match the animals with the places where it lays eggs.

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Animals lay their eggs in places where the young animals can continue to live once they are hatched.

Butterflies lay eggs on leaves. When the eggs are hatched, the caterpillars can feed on the leaves until they become adults.

Mosquitoes lay eggs in stagnant water. They complete their life cycle in places where they lay eggs.

But some mosquitoes complete their life cycle in clean and shallow water.

Other mosquitoes lay eggs in dirty stagnant water like canals. When the eggs hatch, they can continue to live here. They swim and get food in the water until they become adults.

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Flies lay eggs in dirty places like garbage and decaying matters. They also lay their eggs in animal and human wastes. They hatch their eggs here. They become adults here because they find enough food in these dirty places.

Cockroaches lay eggs on papers, books, clothes and other objects that are kept in dark places. When their eggs hatch, the young cockroaches feed on clothing, paper, and garbage. They stay in dark places during daytime and come out at night to look for food.

Self Test (Lesson 2)A. MATCH THE ANIMALS IN COLUMN A WITH THEIR LIFE CYCLE OR STAGES OF DEVELOPMENT IN COLUMN B. Column A 1. 2. 3. 4. 5. cockroach frog chick mosquito fly a) b) c) d) e) f) Column B egg, nymph, and adult egg, larva, pupa, and adult egg, then hatches after 21 days egg, tadpole, adult egg, larva, maggot, adult egg, adult, and larva

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B.

CHOOSE THE ANIMALS WHICH UNDERGO SEVERAL CHANGES AS THEY GROW. 1. 2. 3. Fly Dog Frog 4. 5. 6. Cat 7. Butterfly 8. Pig Chick Cockroach

C.

NAME THE STAGE THAT IS MISSING IN THE LIFE CYCLE OF EACH ANIMAL BELOW. 1. 2. 3. ____________ Mosquito egg Butterflys egg tadpole larva larva adult frog adult adult

mosquito butterfly

AFTER WRITING YOUR ANSWERS, RAISE YOUR RIGHT HAND TO SHOW THAT YOU ARE READY FOR THE GROUP DISCUSSION.

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LESSON

3

Harmful Animals And How To Control Them

In lesson 2 you studied some animals that lay eggs. You also learned how these animals grow and develop. Do you see these animals in your homes? Which of these animals do you like? Why? Which of these dont you like? Why? Cockroaches, mosquitoes, and flies are harmful animals. Harmful animals are animals that can cause damage. Look at these pictures.

Why are flies harmful? Flies move around. They step on clean places. They also step on dirty places like garbage and other waste materials. They step on food. As they move around, they carry germs and dirt from garbage, human and animal wastes, and decaying materials. When these animals step on food, they leave germs. And when a person eats this food, he/she takes in germs which may cause dysentery, cholera, or other diseases.25

A person who is sick with cholera has diarrhea or loose bowel movement. He/ She may die because of loss of water in the body. Cholera also causes stomachache. The picture below shows dysentery germs

Cockroaches are found in storerooms, cabinets, and garbage places. They are also found in the kitchen. Why are these animals harmful? Cockroaches eat different kinds of food. They eat sweet and starchy food. They also eat clothes, paper, and garbage. Cockroaches have bad odor. They spread germs on the things they step on. These germs can cause diseases.

Why are mosquitoes harmful? Mosquitoes carry disease germs. They carry the germs which cause malaria and H-fever.26

A person who is sick with malaria, has many malaria germs in his blood. When the mosquito bites another person, it transfers the germs to the other person. The same thing happens when a mosquito bites a person with H-fever. When it bites a healthy person, H-fever germs are transferred to that person. H-fever often occurs among children. It causes high fever and loss of blood. This drawing shows a mosquito that carries malaria germs.

This drawing shows a mosquito that carries H-fever germs.

Flies, cockroaches, and mosquitoes are harmful. They are harmful because they carry germs that can cause diseases. How can we control these animals? How can we control them so that they cannot multiply and cause more harm? Look at the pictures below. What are these people doing to control these harmful animals?

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The pictures you have just seen show how to control and destroy mosquitoes. Here are the ways of controlling mosquitoes: 1. 2. 3. Eggs, larvae, and pupae of mosquitoes are found in stagnant water. So, remove all stagnant water in your home. Cover your water containers like jars so that mosquitoes cannot lay eggs in them. Put oil on stagnant water. Larvae and pupae of mosquitoes breathe on the surface of the water. If you put oil on stagnant water the young mosquitoes will die because they cannot breathe. You can spray mosquitoes with insecticides to kill them. However, you must use insecticides properly because they are harmful to people.

4.

How can you control cockroaches from multiplying? You have studied that cockroaches lay eggs in dark places like closets, drawers, cracks, cabinets, and garbage. To prevent them from multiplying do the following:

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1.

Always clean your storerooms, cabinets, and closets.

2.

Destroy all cockroach eggs that you find.

3.

Empty and clean your garbage containers often.

4.

Keep your rooms dry and clean.

5.

Seal all cracks where these cockroaches can hide.

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6.

Spray insecticides in places where cockroaches usually go.

You have learned where flies lay eggs and complete their life cycle. How can you control and destroy flies? Here are some ways to destroy and control them: 1. Burn or bury garbage and decaying materials.

Flies would not have a chance to feed and lay hundreds of eggs if the surroundings are free from garbage and waste materials. 2. Help in the cleanliness campaign.

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3.

You can use insecticides to destroy flies. When using insecticides you must remember the following: a) b) c) Cover food and utensils before spraying. Keep your nose and mouth covered with a clean cloth while spraying. Wash yourself very well after spraying.

Self Test (Lesson 3)A. Choose the correct answer and write only its letter in your answer sheet. 1. At what stage of the life cycle can you easily destroy mosquitoes? a) adult b) pupa c) larva 2. At what stage of the life cycle can you easily destroy flies? a) eggs 3. b) adult c) pupa

What diseases are transmitted by mosquitoes? a) b) c) malaria and H-fever diarrhea and dysentery cholera

4.

What harmful animals in your homes crawls on foods? a) mosquito b) cockroach c) fly

5.

Which of these animals carry germs that can cause cholera or dysentery a) flies b) mosquitoes c) cockroach

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B.

Copy the ways of controlling the following animals: 1. Flies 2. Burning or burying garbage Using insecticides Throwing garbage in your backyard Helping in the cleanliness campaign

Mosquitoes Cleaning your cabinets and closets Removing all garbage in the house Removing stagnant water Covering your food Cockroach Cleaning storerooms and cabinets Sealing cracks in the house where cockroach live Burying garbage or burning them Using insecticides

3.

AFTER WRITING YOUR ANSWERS, RAISE YOUR HAND TO SHOW THAT YOU ARE READY FOR THE GROUP DISCUUSION.

SummaryYou have learned many things in this module. Animals produce other animals like themselves. This process is called reproduction. Animals reproduce in different ways. Some animals come from eggs. They start their lives outside the bodies of their mothers. Some animals are born alive. They start their lives inside the bodies of their mothers. Some animals that hatch from eggs change as they grow. They start as eggs, then they become larvae, then pupae, and finally they become adults.32

Some animals are harmful. Mosquitoes, flies, and cockroaches are harmful animals found in our homes. They can be controlled or eliminated by keeping our homes clean and by removing or destroying the places where they grow. You can also use insecticides to control them but you should use them properly. Insecticides are harmful to peoples health.

WHEN YOU ARE READY, GO TO THE TESTING ROOM AND TAKE THE POST TEST.

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