Afaq New Sun Series - Science 5 - Chapter-1

Afaq New Sun Series - Science 5 - Chapter-1

Afaq New Sun Series - Science 5 - Chapter-1
Unit-1 Classification of Living Things
All living things have some characteristics which are the same and some which are different. This feature can help us divide living things into two major groups i.e. animals and plants. These are classified further into subgroups.
Observe your surroundings and list a few different living things you will find, such as flowering plants, non-flowering plants, insects, birds, and fish. Now, try to arrange them in groups on the basis of similarities and differences among them.
This categorization is called classification. It can be defined as a method used by scientists to order living organisms into different groups. Therefore, scientists make a key to tell what organisms they are and which group they exactly belong to, and this dey is called a classification key. Classification is essential because it helps scientists to identify organisms and break them down into groups.

Five-Kingdom Classification
According to this systematic method, scientists classify living things into kingdoms which are given below along with examples of lining organisms that belong to these kingdoms.

Let's discuss each of them.

1. Kingdom Monera:

The Kingdom monera consists of all bacteria. They are single-celled or unicellular organisms. They are present all around us, but not visible to the naked eye because they are present all around us, but not visible to the naked eye because they are microscopic in size.
Like plants, some bacteria can make their own food. That the same time some depend on others and live in the bodies of other living organisms or dead bodies. They are dependent on other organisms in tow ways.
a. Many bacteria get food directly from dead bodies.
b. Many bacteria make a relationship with the organism (host) whom they are getting food from.
Some of these bacteria cause disease in host organisms, while some benefit to them. Some are neither useful nor harmful to these organisms.

2. Kingdom Protista

The best example of the kingdom Protista is algae. They can be unicellular, multicellular, or colonial. Algae are found in ponds, rivers, lakes, etc.

They have the characteristics of both plants and animals as some of the algae can prepare their own food by the process of photosynthesis because they have chlorophyll. However, they are not classified as either of the two. Euglena, Spirogyra, volvox are examples of algae.

3. Kingdom Fungi
Fungi can be unicellular, Multicellular, or filamentous (thread-like structures). Fungi cannot prepare their own food because they lack chlorophyll. They grow in damp and moist places. they get their food from dead matter and cause disease in living organisms.

The Kingdom Fungi includes yeast, mushrooms, rhizopus, puffballs, etc.

4. Kingdom Animalia
 All organisms in this group are multicellular. They cannot prepare their own food so they depend on plants and other animals for their food. This is the largest kingdom and is classified further into tow large groups.

a. Vertebrates have a vertebral column or backbone in their skeleton that helps them in movement and provides support. Different organisms have different structures o the vertebral column.

b. Invertebrates do not have vertebral column or backbone. This group covers almost 97% of all known animal species on earth. since they have no rigid support in the form of a backbone, They have another system that provides enough support to their bodies. For example, invertebrates like insects have a hard outer shell or support. Their outer covering or shell is called an exoskeleton, i.e. the skeleton outside the body which is made of chitin, a tough semi-transparent substance. Other examples are the Jellyfish, earthworm, crab, octopus, starfish, etc.

5. Kingdom Plantae
This kingdom consists of plants. They are multicellular organisms. They are also called autotrophs because they can prepare their own food. There are two main groups of Plants, i.e. flowering and non-flowering plants

a. Flowering Plants have flowers on their stems. They produce seeds,  which are enclosed in flowers or fruit.
Rose, oranges, apple, wheat, rice, and sunflower plants are some of their examples.

b. Non-Flowering Plants do not have flowers on their stems. Conifers are examples of non-flowering plants. Their seeds are not enclosed in fruits or flowers. They have needle-shaped leaves that have seeds inside them. These leaves spread by wind or water, which helps in their reproduction. Most non-flowering plants reproduce by releasing large numbers of tiny spores.