Plants are the most robust and oldest forms living organisms on the earth.
The earth is called a green planet due to the plants on it.
There are different types of plants based on their habitat, regions and climates.
They can be classified based on many factors like their life span, physical appearance, reproduction, presence of flowers, habits, food requirement, etc.
But taxonomical classification of plant relies on specific features which run through a set of plants.
This botanical classification is more precise to read for academics but for knowledge purposes we can see them more differently.
Different types of plants are
1. Based on age or life span: Plants are the longest living creatures on the earth. Some of them live for even 1000 to 5000 years are more. But not all plants live the same age. Some of them even die within months. So plants are differentiated based on their live span as
These are the plants with short life span. They live for only few weeks.
They germinate, grow, reproduce and die within few weeks.
These are present even in deserts
These plants survive for a year or less.
Ex; cotton, wheat.
Most of the agriculture crop plants come under this category.
Biennial plants: These plants survive for two years at most. Ex: Carrot
Perennial plants. These plants grow for many years. Their actual age is not fixed. Some are either cut off or broken due to winds etc. If not they live for hundreds of years.
Ex: Neem, banyan, mango, etc.
2. Based on where they grow: The plants can also be differentiated based on places where they grow. They are quite interesting like
a. Mesophytes– These are land plants which grow at the normal land condition with sufficient water in the soil to live.
These are the plants which we see around us every day.
They can be big trees, shrubs, bushes, plantains, etc.
As the name indicates these plants grow only in water
Water plants live in water whole life.
They germinate, grow and survive in water.
They cannot survive in the plain soil.
c. Xerophytes: These are plants which grow in desert areas with very low water availability and heat temperatures. They can survive in drought conditions like the desert. Ex: Cactus.
They live in dry areas so-called “xerophytes” as xero- dry + phyto- plant. These plants save water for use in drought in leaves or stems.
So their leaves or stems are succulent i.e., a bid bulged and soft. When squeezed you can find a paste like liquid oozing out. Further, the leaves have thorns which are meant to prevent animals from grazing on them.
d. Epiphytes: Epiphyte is a plant that grows on the surface of other plants. Ex: Fern, mosses, etc. These plants are not parasites but survive on other big and tall-growing trees.
The reason is in dense forests these plants will be deprived of sunlight on the land due to other big trees shading them. So when they grow on other plants, they can overcome this. They can get the sufficient sunlight for photosynthesis. They grow on other plants so epiphytes as EPI– above (top) PHYTO– plant.
3. Based on physical size: Have you noticed? Not all plants are of the same size. Some are tiny while some are very gigantic. Based on this physical size, there are different types of plants.
- Herbs: Small plants with a height in few centimeeres or a foot. Ex: grasses.
- Shrubs: These are quite bigger than herbs, till a meter or more Ex: Basil plant
- Trees: These are gigantic plants. They grow upto few meters in height and also live for long duration like hundrd years or more. Ex: Neem plant.
4. Based on seed types: Seed is the key part of a plant. it is one which gives rise to a new plant. It is also the one from which other animals derive nutrition. But not all seed are alike so, we can differentiate the plants based on type of seeds as
A.monocotyledons: Seed appears as a single entity. Ex: Wheat, rice etc. Their seed has a single cotyledon. These monocots have adventitious roots with long leaves with parallel veins.
B.dicotyledons. Seed can be broken into two equal halves. Ex: Cashew nut, Pea nut etc. Each half is a cotyledon.
Dicots have taproot system and leaf veins show reticulated arrangement. See more differences here.
5. Based on cell numbers: Plants like animals are made of cells and cell organelles. Plants can be classified based on cell numbers in their body as
a) Single cellular (unicellular): Ex; Bacteria, algae. These are single celled plants. Bacteria are called plants due to cell wall on their cell membrane. Algae are plants which grow in water or moist places. Single celled algae include chlorella, diatoms. Algae have ability of photosynthesis.
b) Multi-cellular: Ex: Fungi & algae; Fungi have many cells linked to one another but still each cell survives on its own. But unlike algae they are saprophytes. Some of them are also parasites.
C) Organ based: These are plants whose cells form tissue and differentiate into organs like leaves, roots, branches, stem, fruit, etc. They are large plants and trees coming under this group. We see these plants in daily life around us.
6. Based on Gametes: This is an advanced feature among plants. Formation of male and female gametes for sexual reproduction is thought to be an advanced feature in evolution.
Plants with gametes are called gametocytes and those without gametes are termed Agametocytes.
7. Based on the cover on seeds: Gymnosperms and angiosperms. Most of the plants we see around have a prominent seed coat around the see. Some of them even have a fruit pulp around the seed formed from the flower. These plants are termed as angiosperms or flowering plants. But there are few plants whose seeds are naked and called as gymnosperms.
8. Based on food habits: This is quite interesting. We get food from plants as they make their own food (Autotrophs). But some are even carnivores. They eat animals. So we can call the plants as
a. Autotrophs: These plants create their own food by use of sunlight. They can do so due to their ability to trap energy of sun light in their leaves due to pigment chlorophyll. Most plants on earth are autotrophs.
b. Carnivores: These plants produce own food, but also eat other insects and animals when they come near to.
Ex: Nepenthes, Venus fly trap.
These plants grow in nitrogen-deficient soil. So for the sake of nitrogen in the form of ammonia, they trap insects and small animals. They either have a cavity to trap and close the insect or have a glue like secretion to trap insects.
C. Parasites: These plants depend on other plants for survival.
Hence name parasites.
9. Based on root type
Also, plants differ based on their root system as
A) Tap root plants
B) Fibrous root plants
Tap root: These plants have deeply-rooted structure. Roots penetrate very deep into the soil. Due to this they can stand against strong winds and bear massive trunks and branches. Ex: Trees like neem and shrubs like cotton.
Fibrous root plants: These roots are small and bushy. They penetrate just upper layer of soil and can be easily pulled from soil.
Ex: Wheat and rice plants.
Plants provide food, shelter, medicine, bring rainfall and reduce pollution. So, we need to conserve their diversity.
Based on flower type: Flowers are the most beautiful parts of a plant. They are so good looking to attract animals and enable cross pollination. They have pollen grain and also female gametes within them and hence they are genital organs of the plant. The flowers of different plants vary greatly. And the taxonomic classification of plants depends to a large extent on the the flower structure and arrangement of its petals. However, flowers are either simple type with a single flower or complex type with multiple small flowers arranged together called as inflorescence.