why do some plants grow from parts of old or parent plant?
341396
It is the vegetative propagation.In the vegetative propagation no variation takes place in the next generation.It is the adaptive process in the struggle for survival,where sexual reproduction is not possible.Some plant adopt dual security by adopting both the kind of reproduction.It is the mechanism of  evolution,to make survival of the plant  possible.
765397
none primary succession is the first stage of growth in a devastated area ( like a volcanic eruption ) with no soil ( or very little ) the progression would be mosses or lichens then grasses then shrubs then trees ( but then you are in secondary succession )\n\nwhen the trees do appear the local climate determines the first species you would not have the same tree after Mount Saint Helen's as you would a Pacific Volcano
158418
There have been several experiments to see if this was the case.  The first one stated that classical music helped plants grow much better then other forms of music.  However, more experiments since then have shown that there is no link to plant growth.
244312
It would depend on the species of tree. Some seeds need things to happen to them before they can sprout, such as being buried for a while and then unearthed, or drying out and getting wet again, or passing through the digestive tract of a bird.
643651
Some plants are notorious self seeders.  Their seeds drop very easily and grow even easier.  Others depend on insects and birds to pick up their seeds and spread them.
211168
Because there isn't a natural process kicking out more of them. Photosynthesis actually synthesizes more of the biotic elements in plants that we find useful.\n\nThe difference is, as your own question alludes to, the same as that between new manufacturing and recycling.
862372
Because light is needed for photosynthesis which makes energy..since the seeds have no leaves and hence no photosyntheisis they get around by having enough energy material provided within the seed to allow for growth until plant is above ground and has the leaves needed for photosynthesis
406714
plants and roots of plants
799857
apical meristem. thats where all new growth on a plant comes from. however, if its cut off, a most plants can create a new apical meristem.
590556
The primary succession starts with bare rock, lichens grow on rocks, moss grows on lichens, grass grows on moss. \nThe secondary succession starts with an area that has been disturbed. Ex: abandoned farm, forest that has burned
735244
Asexual reproduction is cloning. A piece of a plant may root or sprout and grow into a new plant which is genetically identical with the parent.  \n\nSexual reproduction results in a new plant which contains genetic material from two parents, but which is not genetically identical with either one.   These new plants may be able to adapt more successfully to environmental changes than their parents could.\n     To live and multiply on land, plants needed to evolve new structures and methods for reproduction.  An important advance was the development of the flower, a structure which allowed widespread scattering of its pollen and yet provided a stable, nurturing environment in the ovary for developing seeds.  Pollen could be carried from flower to flower by insects, the wind, or, sometimes, birds.  \n\n     The seed was another important innovation, as significant for plants as the amniotic egg was for land animals.  Seeds would form when the chromosomes of the parents were united in the ovary.  A seed is a compact package made of a cell capable of growing into a plant, food to help the plant get started, and, in angiosperms, a seed coat that protected the seed from dehydration  and  damage in the environment.  Properly protected seeds could survive until conditions favored their development.  In the deserts today, some seeds may lie dormant for many years until the rains come and provide conditions in which the seeds may germinate and grow into plants.  Some seeds also are contained in, or attached to, structures which help the seeds to be carried to other places that may be suitable for them.
116027
Even though seeds aren't the earliest to hit the scene in plant evolution, as Djddan has stated, they have played a HUGE role in evolution...\nThe main thing is that seeds have given their parent plant an opportunity to travel! In general, plants are stationary organisms. Without means for locomotion (like most animals have), they must rely on their seeds to move for them. The reason is that it increases the area their genetic material can travel.\nIf seeds didn't travel, you would have huge pockets of areas that would have many genetically similar plants.\n\nSeeds ensure travel many different ways. Some have wings on them so that the wind can carry them away from their parent tree. Some are embedded in tasty fruit thhat get carried off by hungary animals. Some stuck to animals walking by, some are dropped into water and carried off by flowing rivers...The list goes on.\n\nSeeds have impacted evolution in huge ways. Hope this helps.
331011
the flower is what separates it from other plants, attracting birds and insects to pollenate the plant. however the plant requires all of its "parts" for survival, eg leaves with chlorophyll for photosynthesis, roots for water and ion uptake, and the stem with the xylem and phloem for water nutrient transport. so, no part is superior to another, but the flower appears to be the most "advanced" part.
1080381
Dear Avi,\n        You should have asked your question more clearly. Maybe, you are referring to the different varieties of plant tissues. In plants, basically, there are two types of tissues i.e. Permanent and Meristematic. Permanent tissues are those tissues which contain the cells which do not have the ability to divide. On the other hand, Meristematic cells can grow. Meristematic tissues are further divided into many groups like Ground tissues, Supporting tissues, Epidermal tissues, Conducting tissues.\n\nHope this helps!!
426558
Secondary growth does occur in a few monocots but it developed independently of secondary growth in dicots. If you look at a basic plant anatomy book (the one I have is by Katherine Esau) you will see that dicots have their vascular tissue in a ring in the stem. In dicots with secondary growth (shrubs and trees), the cambium generates new vascular tissue in a ring and the stem expands outwards. In the monocot stem, the vascular bundles are scattered throughout the stem tissue and there is no "natural" way for the stem to expand. \nA very different form of secondary growth is found in only a few mostly tropical monocot genera.  Secondary thickening in these monocots results from the activity of a special cambium called the 'secondary thickening meristem' and results in what is called 'diffuse secondary growth'.  This unusual cambium develops in the parenchyma of the stem.  It is external to all of the primary vascular bundles and it produces 1) new secondary vascular bundles and parenchyma toward the inside of the stem along with 2) a small bit of parenchyma to the outside of the stem. This kind of growth has also been called "dracaenoid" because it is characteristic of the growth of Dracaena (especially in D. draco, the "Dragon's Blood Tree").
825982
there are tons of factors affecting plant growth. one of them is the kind of soil for the plant to grow. some plants need a specific type of soil in order to grow properly. another factor is the sunlight and food it gets. it needs the propwer nourishment for the palnt to fluorish. next is the nutrients that a plant need. some may need medicines to help them grow better.
675640
In one seminar I attended, on plants containing pharmaceuticals, the speaker commented that they may have first arisen as an accidental byproduct of the plant's own metabolism.  They lack an excretory system, so they can just shed odd compounds into old leaves, bark, etc, to get them out of living cells.\n\nIf the plant is then under attack by an insect (or other small animal, eg a slug or snail) that tiny herbivore may spend much of its life cycle feeding on a certain plant.  Thus, that animal gets a huge dose of whatever odd compounds the plant has made.\n\nIf these compounds slow down that animal, by killing it, or just confusing it so it drops off the plant, this characteristic will confer a selective advantage to that plant.  It may lead to more of the toxic compound being made, not less.\n\nHe said that these effects are less likely to be useful in deterring larger animals, for whom a certain plant species might form a very small % of a browsing (or gathering) diet.