Current Affairs 6th Class

Category : 6th Class

The Living World

• There is a variety of living organisms around us. Each one of them possesses a definite shape, size, structure and a colour pattern Similarly, things like living places (water and land), home (nests holes of trees), food habits, etc., give each organism a different identity.
• Each kind of organism has many individuals. There are differences and similarities among the individuals of a kind based on which they can be recognised.
• The individuals of a kind have a similarity in their body parts and their functioning. They eat the same kind of food and live in the same habitat. They cooperate among themselves for reproduction. Such a group of similar individuals is known as species. Each species has a name.
• Each plant and animal has a scientific name consisting in two words. These scientific names help us in identifying each type of plant or animal and the group to which it belongs. When they are written the first letter of the first word (group name) is always written as a capital letter, but the first letter of the second word (individual name) is written as a small letter.

Note: Although in different languages the plants and the animals may be called by different names, their scientific names are the same all over the world.

• Living organisms are very different in shape, size, habitat, food habits and behaviour. They breathe in different ways and move around in different ways. They even have different ways of growing and reproducing themselves. All have different names but despite all these differences, they all have one most important thing in common—they are all living.
• The living organisms share some features with the non-living objects. All living and non-living objects are made of matter. They all have mass and occupy space. But life is the process seen only in living objects in the form of growth, movement, feeding or eating, sensitivity, respiration, excretion and reproduction.
• The world of living organisms can be divided into two groups:

(i) plants and (ii) animals.

• An important difference between plants and animals is the way they obtain their food. Most animals, being able to move around, obtain food by looking for and going after it. However, most plants are fixed. They manufacture their own food. The process by which they manufacture their food is called photosynthesis.
• Plants and animals reproduce themselves. They produce one or more individuals of their own kind. Plants reproduce mainly through seeds or spores. Certain plants reproduce through leaves, for example, Bryophyllum. Some also reproduce through stems, like ginger, potato. Animals reproduce by laying eggs or by giving birth to babies.
• Both plants and animals can respond to changes in their surroundings. These changes, which they respond to, are called stimuli.

CLASSIFICATION OF PLANTS

• Plants can be classified into different groups based on certain characters. There are two main groups - (i) flowering plants and (ii) non-flowering plants.

(i) Flowering plants: These plants have roots, stems, leaves, flowers and fruits.

(ii) Non-flowering Plants: These plants do not bear flowers.

CLASSIFICATION OF ANIMALS

• Animals can be classified based on certain characteristics. All the animals can be separated into two main groups: (i) vertebrates and (ii) invertebrates.

(i) Vertebrates: Animals with a backbone are called vertebrates. For example: lion, frog, dog, cow, etc.

Note: Inside the body of some animals, there is a bony skeleton. The backbone is a part of the skeleton. It is made up of several small bones called vertebrae.

(ii) Invertebrates: The animals that have either a backbone or a bony skeleton are called invertebrates. For example: earthworm, oyster, amoeba.