Modes of Reproduction in Animals

Modes of Reproduction in Animals

By John Daniel P. Gumban

Introduction

Animals cannot live forever. Like humans, animals also need to reproduce. They have also their own reproductive system that makes them able to do such life process. Most of them performs sexual reproduction involving male and female animal. In this way, extinction is prevented and diversity is maintained in nature. Producing new animals may mean food supply to other organisms. It may also signal the continuous existence of certain species.

Introduction

This lesson will help you understand how animals produce their offspring (new young). Doing the different activities of this lesson will direct you to describe the reproduction depending on the level and type of animals.​

Discussion

Animals have the means to increase their number through reproduction. This is to preserve their species and to help in keeping the nature balance ay they interact with other animals. Different animals have unique modes of reproduction. It can be noticed that some animals can reproduce in large numbers like insects, pigs, dogs and frogs while some animals can not. On the other hand, those big animals generally reproduce in fewer number.

Draw

Learning Task 1: Encircle the animals that can reproduce in large number.

What are the animals that can reproduce in large number?

Most of the animals like cats, dogs, butterflies, frogs and the like need a male and a female to reproduce. This is called sexual reproduction. Sexual reproduction is a process of creating offspring with the participation of sperm cell from male parent and egg cell from the female parent.

​Some text here about the topic of discussion.

Two Parents

​

Single Parent

Learning Task 2: Identify whether the following animals are reproducing sexually. Write TWO PARENTS if the animal shows sexual reproduction. Otherwise, write SINGLE PARENT.

Multiple Choice

1. Dolphin

• Two Parents

• Single Parent

Multiple Choice

2. Sea Anemone

• Two Parents

• Single Parent

Multiple Choice

3. Panda

• Two Parents

• Single Parent

Multiple Choice

4. Sea Sponge

• Two Parent

• Single Parent

Multiple Choice

• Two Parent

• Single Parent

​Describe how a frog grows. Why do you think the eggs are found in the water? Where do you think fertilization happens?

​​Frog

Describe how a dog grows. Describe their mode of reproduction.

Dog

Learning Task 3: Study the figures below. The first picture shows a frog in its natural environment. The second picture shows a pregnant dog.

Reproduction involves the transfer of characteristics of parents to their offspring or young. During fertilization (meeting of egg and sperm cell), genetic materials like DNA (deoxyribonucleic acid) are shared by the parents to produce new organism that may either be possessing unique characteristics or having an exact copy of what the parent has.

In sexual reproduction, new animal with a set of unique characteristics is produced. This means that the offspring is quite different from its parents. Sexual reproduction always involve the presence of sperm cell and egg cell. These two cells carry the genetic materials from the father and mother respectively.

Dogs, cats, mosquitoes and butterflies reproduce sexually. Among these animals, sperm and egg cells meet inside the body. This called internal fertilization. Unlike among frogs, they also reproduce sexually but fertilization occurs in the water or outside the body. External fertilization happens when both male and female frog release sperm and egg in the water to form fertilized eggs.

Draw

Learning Task 4: Think of two animals that can reproduce sexually. In the first box, draw an example of an animal that exhibits internal fertilization (fertilization occurs inside the body) . In the second box, draw an animal that exhibits external fertilization (fertilization occurs outside the body or in the outside environment).

Animals may also reproduce asexually. Asexual reproduction only needs one parent. Most common activities under asexual reproduction are budding and binary fission. Budding happens when a new animal is produced through outgrowth parts of the parent. Aquatic animals like hydra and jellyfish are doing this process. On the other hand, binary fission which is performed by sea anemone occurs when the parent animal divides into two. It means one animal (parent) results into two new individuals.

Terminology to be memorize​:

Reproduction - ​involves the transfer of characteristics of parents to their offspring or young.

​

Types of Reproduction in Animals

1. ​Sexual Reproduction - process of creating offspring with the participation of sperm cell from male parent and egg cell from the female parent.

   (examples: ​Dogs, cats, mosquitoes and butterflies)

2. Asexual Reproduction - ​only needs one parent.

   (examples: ​Aquatic animals like hydra, jellyfish and sea anemone)

Terminology to be memorize​:

Fertilization - The process of combining sperm cells and egg cells

​

Modes of Fertilization

1. Internal Fertilization - ​sperm and egg cells meet inside the body of parent animals. (Example: cat, dog, horse)

2. External Fertilization - ​happens when both male and female frog release sperm and egg in the water to form fertilized eggs. (Example: frog, sea horse, clown fish)