All plants are multi-cellular, eukaryotic and autotrophic. Plants make their own food by the process of photosynthesis.
In order for plant to survive on the land, it needs several adaptations.
A: Plants need water and need to absorb water from the ground.
B: They need a transporting system to transport the water from the roots to other parts of a plant.
C: They need to retain water. Leaves have a waxy covering called cuticle to avoid water loss from a plant, process also called as transpiration.
D: Plants need support which is provided by the vascular tissues.
E: Plants need to reproduce.
Plants are divided into two types: Vascular and Nonvascular.
Nonvascular plants lack the transporting system and hence grow low to the ground.
Examples of a nonvascular plant are Moss, Liverwort and Hornwort.
Vascular plants have a transporting system and can grow tall. The transporting system is made up of vascular tissue. There are two types of Vascular tissues: Xylem and Phloem.
Xylem transports water and other nutrients while phloem transfers food.
Some Vascular plants can be seedless (reproduce by spores), some have seeds that are not enclosed (naked seeds), while some plants have seed that are enclosed.
An example of a seedless vascular plant is a fern. Fern reproduce by using spores. Like moss, fern undergoes two generation during reproduction: Sporophyte and Gametophyte.
Plants that produce seed that are not enclosed (naked seeds) are called Gymnosperms.
Examples of a gymnosperm are cycads, Conifers like junipers, pine, Gnetophyte. The reproductive structures of most of the gymnosperms are called as Cones. Some plants produce both the male and female cones on the same plant while some plants only produce male cones and others only female. The pollen from the male cone falls on the female cone and fertilization takes place.
Plants that produce enclosed seeds are called as angiosperms. Examples of an angiosperm are apple, tomato, bell pepper, and orange. Characteristics of an angiosperm are that they
all produce flowers and fruits. The function of the flower is reproduction. A flower has both the male and female reproductive parts. The female reproductive part is called pistil and is made up of stigma, style and ovary. The male reproductive part is called as stamen and is made up of anther and filament. The anther has pollen. During pollination, pollen is transferred from male reproductive part to female reproductive part. Fertilization takes place where male and female sex cells join together forming a zygote, inside the ovary.
Seed is formed inside the ovary and the parts of the ovary turn in to a fruit.
A seed is a plant structure that consists of a young plant inside a protective covering.
A seed is made up of three parts. Seed coat which helps in protection, embryo which grows into a new plant and a cotyledon which stores food.