Plants go through various stages to reach maturity. These stages include germination, seedling development, vegetative growth, flowering and fruiting.
Within each seed lies an embryo of a young plant with roots and stems, waiting to sprout when found in rich soil with plenty of moisture and an ideal temperature. Once it finds this ideal environment, growth starts through germination.
Seeds
Seeds are miniature replicas of plants that contain embryos or baby plants protected by an outer protective shell known as a seed coat. Seeds are dispersed through various means: floating on water, carried by animals, eaten and passed along the digestive tract – until conditions allow it to germinate into something bigger – known as “germination.”
Seedlings have the ability to form roots that absorb water and nutrients from their soil surroundings, as well as to start photosynthesis – using light energy from sunlight combined with carbon dioxide into a food source for themselves. As they mature further they develop leaves to protect themselves against weather extremes, competition among plants, or predatory attacks from birds or mammals.
Most plants possess a diploid sporophyte that reproduces by meiosis to form haploid gametes, or sperm and egg cells. A few species, however, reproduce asexually using structures called bulbs buried underground that later sprout a new plant the following year – such as Daffodils and Snowdrops which reproduce this way.
Once a plant reaches maturity, it begins producing flowers and seeds. Pollinators such as bees or wind fertilize these blooms; fruit then contains their seeds – starting a cycle once again! Some plants are biennial in that their reproductive phase begins again the following year while other must complete reproductive phase and produce seeds by season’s end or they won’t survive.
Seedlings
Seeds contain the embryo of a plant and are protected by an outer coat. When they arrive at their final destination with all the right elements such as water and temperature conditions, their embryo starts developing into what we know as “germination”.
Once plants reach a certain size, they begin producing flowers (in flowering plants) or fruit. Fertilized flowers produce seeds which deposit themselves within fruit; animal consumption disperses this fruit further to new locations; wind or moving water can help disperse it further still; some trees even explode when their fruits are ready, sending their seeds hurled as far as 100 ft away! One such tree, known as the Dynamite TreeTM produces fruit which explodes when fully ripe to disseminate its seeds further than ever.
Sperm and ova of plants are multicellular haploid cells that make up the gametophyte generation in their lifecycle, living within leaves and stems producing food via photosynthesis – this explains why plants appear green while their ground dwelling sporophyte generation doesn’t.
As seedlings develop, their roots absorb more nutrients and water through absorption channels; as a result they gain strength, growing larger until reaching maturity and producing seeds to start the cycle anew.
Different plants exhibit distinct growth patterns and can be divided into annuals, biennials and perennials. Annuals such as zinnias have one growing season or year to complete their life cycles while biennials such as okra take two years before reaching completion; finally perennials like kale can last decades.
Vegetative Growth
Plants increase in size through both cell growth and division (mitosis). During vegetative growth, cells stretch continuously while new tissues develop; this is how plants increase in size. Their main means of transporting water and nutrients at this stage is through its vascular system – composed of tubes called xylem and phloem. Xylem tubes carry water with dissolved minerals while the latter transport food such as sugars. In addition, its vascular system produces meristem tissue layers which continuously produce new cells to support its continued lengthening and width increase.
Seeds contain embryos with roots and shoots as well as their first leaves, protected within their outer coating. When exposed to optimal conditions (oxygen, temperature and soil), seeds begin to germinate – this process is known as germination. Seeds require three essential elements for full germination: oxygen, temperature and place.
Germination occurs when a seed’s outer shell is cracked open or split open, exposing its embryo and allowing it to expand and swell up. As soon as this process takes place, a tiny baby plant known as a seedling begins forming from its embryo’s roots – drawing in water, nutrients, and energy from sunlight through photosynthesis.
At its vegetative growth stage, a plant will continue to expand until reaching maturity. Plants with flowers will produce fruits and seeds while those without will simply produce spores which are dispersed via wind or animals. All types of plants eventually die off; their seeds and spores being spread further to continue the cycle.
Flowering
Plants develop roots, stems, leaves and flowers to produce food and reproduce themselves. Energy for photosynthesis comes from sunlight; carbon dioxide, water and sunlight combine into sugars and starches that the plants store in their roots and stem for later consumption as food or to anchor themselves into soil.
Some plants do not require fertilization to reproduce successfully; these asexually reproducing species form bulbs, tubers or tubercles which remain underground until conditions allow new plant formation to take place when conditions are ideal.
At maturity, plants begin producing flower buds as part of their survival strategy and to spread its species further. Many flowering plants feature vibrant colours and scents to attract animals or insects for pollination.
Pollen must travel from its male parts – known as stamen – to its female parts in order for flowers to become fertilised. Stamen contain filaments which produce small grains of pollen which must reach its final destination: stigma. Some flowers contain both male and female parts while others only possess male (hermaphrodites) or only female carpels (carpels).
Flowers are enclosed within protective cases known as calyxes or corollas to maintain their beauty, with petals forming an eye-catching display while stamen and carpels remain concealed within. Pollens dispersed from petals stick to stigmas which then travel down through styles to reach the ovary through which fertilised eggs will mature into seeds that will spread by wind or animals, creating more plants in turn.
Fruits
Seed-bearing plants reproduce via asexual reproduction; pollination, fertilization and seed production constitute sexual reproduction. Seeds are the smallest forms of plants which begin their journey toward becoming fully grown adults – whether dispersed by wind or water and sprouted into seedlings in other locations; later these seeds bloom into flowers that bloom into flowers that attract pollination from nearby flowers – again creating another mature plant producing seeds until it reaches maturity and starts making fruit or seeds of its own.
A flower’s central ovary (carpel) develops into fruit after being fertilized by pollen from its outer parts, such as sepals and petals, becoming fertilized. Pollen travels from stamens to the carpel’s ovules where male reproductive cells called pollen fertilize female reproductive cells called gametes in turn producing seeds from each fertilized ovule.
Fruits consist of three layers of tissue known as exocarp, mesocarp and endocarp. The outermost layer, known as the pericarp, can range from hard (like in stone fruits like peaches) to soft and membranous (such as in tomatoes). The middle layer known as mesocarp tends to be thicker for fleshy fruits than dry fruits while its innermost layer called endocarp may be soft or dense depending on which kind of fruit it’s on.
Fleshy plants rely on their seeds to spread themselves, as well as animals to disperse them further. Other plants use more creative means: the explosion of a dynamite tree sends seeds flying 100 feet away!