- Life Cycle of a Lily Flower
- Flower Growth Stages
- Life Cycles of Trees
- Life Cycle of a Tulip Flower
- The Life Cycle of a Conifer Plant
- Poinsettia Plant Life Cycle
- Pilobolus Life Cycle
- Plant Project for 1st Grade Science
- Why Are Seeds Cones & Spores Important to Plants?
- How to Plant Grass Runners
- Why Do Plants Have Seeds?
- How Do Ginko Trees Reproduce?
- How Does the Balsam Fir Tree Reproduce?
- How to Prune American Cranberrybush
- How Do Coniferous Plants Reproduce?
Lily plants belong to a large group of plants called angiosperms. This means that they grow flowers to reproduce. Each flower contains the necessary sex organs to produce seeds, thereby continuing the life cycle.
The life cycle of a lily flower begins with a seed. Once mature, the plant reproduces by growing a flower, which is the sexual part of the plant that produces seeds.
Male Sex Organs
The male sex organ is called the anther, and there are several in each lily flower. The anthers produce pollen.
Female Sex Organs
The female portions of the flower are called the stigma, pistil and ovule. The ovule contains the unfertilized ova of the plant.
Pollination is accomplished when pollen grains, the male gametes of the plant, are transferred to the stigma by an insect or other physical action.
The pollen grains come in contact with the stigma and stick to it. Pollen travels down a path called a pollen tube through the pistil into the ovule to fertilize the ova.
Seeds form in the lily flower. As the seeds mature, the flower dies, and a seed pod grows. The pod eventually releases its seeds.
Seeds can lie on the ground for long periods. Most seeds require warmth, oxygen and water to germinate.
When all needs are met, the seed will germinate, producing roots growing downward. A stem will soon begin growing up through the surface.
The seedling appearing will continue to grow taller and produce leaves. The plant will grow into a mature plant and begin to generate flowers.
Pollination is necessary for the flower to be able to reproduce. Wind, water or insects can pollinate flowers. Seeds are produced from this fertilization process.
The flower will ultimately die. The dry fertilized seeds will be discharged into the area or carried off by birds, insects or the wind. This begins the flower growth stages again.
Once planted, a tree seed germinates into a sprout. If weather conditions allow the sprout to survive, it will grow into a seedling, at which point it will change from looking like a plant to developing a thin skin of bark.
Saplings are taller and more mature versions of seedlings. Garden centers typically sell trees at sapling size, as they are the ideal height and build for transplanting.
Saplings become mature trees that sprout branches, grow new foliage and develop fruit, depending on the variety. If the tree does not bear fruit, it might develop buds instead.
A mature tree's trunk grows thicker each year, developing one new layer of bark over top of the old one. According to North Carolina State University, the outer bark layer is dead and helps protect the inner layers.
Mature, dying trees are called snags. Dead trees can remain standing until rotted through or decomposed enough that they fall over.
Tulips in Nature
The tulip adapted to dry summers by developing an underground storage unit (the bulb), which permits it to stay alive through a long dormancy.
Inside the bulb lies everything the plant needs to grow. The dry reddish-brown coat (called a tunic) protects the plant, allowing it to stay dormant until conditions are right for growth.
Awaking From Dormancy
The bulb begins growing immediately after fall planting when it is exposed to moisture in the soil. It goes into winter having already developed a strong root system.
As the weather warms in the spring, the shoot emerges. Depending on the variety, tulips bloom any time from early April to late May.
Returning to Dormancy
The tulip’s leaves convert energy from the sun into food through photosynthesis. The leaves must be allowed to stay on the plant until they wither for the bulb to bloom the next season. The bulb remains dormant through the summer.
The life cycle begins with a seed. Most conifer seeds possess a wing that carries the seed through the air to the ground. When the seed contacts the soil, the embryo inside germinates and sprouts.
Initially, the embryo grows using starches stored in the seed. Eventually, it sends out roots to obtain water and nutrients and a stem with leaves, becoming a seedling.
The seedling continues to grow, putting out more branches, leaves and roots. Once mature, it reproduces, growing cones made of overlapping scales.
Male cones generate pollen, from sex organs called microsporangium. Female cones produce ovules within their scales. The ovules contain mother cells called megaspores.
The megaspores form a megalogametophyte with an archegonium containing an egg cell. When pollen contacts the ovule, male reproductive cells fertilize the egg, which grows into an embryo. The megalogametophyte and embryo become a seed.
When the seeds mature, the female cone opens. Wind and gravity carry them away. If conditions are right, the seeds germinate to restart the life cycle.
A Tropical Bush
The poinsettia is a tropical plant that grows and blooms year after year. Eventually it becomes a bush five to 10 feet high.
Poinsettias grow from seeds, cuttings or shoots. A shoot planted in spring will grow to vegetative maturity by the onset of autumn.
A Short-Day Plant
Some plants called short-day plants will bloom only when their leaves are subjected to darkness for a sufficiently long period of time each night. The required period varies with the species. The poinsettia is a short-day plant. In nature the poinsettia will flower in tropical areas where the winter nights do not exceed 13 hours in length. However, to ensure timely flowering in artificial conditions in the United States, it is recommended that plants be subjected to 14 or 15 hours of complete darkness for eight to 10 weeks in autumn.
The showy red flowers of the poinsettia are actually a whorl of bracts called a cyathium (from the Greek word "kyathos," meaning cup). At the center of this red cup the true flowers rest.
The poinsettia flowers continue to bloom until the end of January or even longer. Then the showy bracts and leaves fall off and the plant becomes dormant.
About the beginning of May, the plant begins to grow again. If subjected to sufficient darkness in October and November, it will bloom again in December.
Pilobolus is a fungi that feeds on the manure of herbivorous animals. Pilobolus is not a parasite that steals nutrients from its host and it does not appear to cause any human, plant or animal diseases. It cannot produce its own food, so it lives on the undigested plants, bacteria, water and minerals ---particularly nitrogen --- in the dung of herbivores.
The Pilobolus life cycle begins when a herbivore defecates. The animal then moves away because animals avoid eating near dung. Pilobolus mycelium, the cobweb-like hyphae through which the fungi eats, grow and feed on the manure.
As the Pilobolus feeds and grows, it develops sporangia, slender stalks topped with small pods that contain the Pilobolus' reproductive spores.
This next step has fascinated scientists since its discovery. The Pilobolus must move because herbivorous animals won't feed near dung piles and Pilobolus needs to be ingested by a herbivore for the essential next phase in its life cycle. So the Pilobolus launches its sporangia into the air, sometimes more than 6 feet. Thus the Pilobolus spreads out over its habitat and significantly increase its chances of being eaten by a cow, deer, horse or other herbivore.
A herbivore feeds on grass containing Pilobolus sporangia. The sporangia passes through the animal's digestive system without harm. The animal defecates the spores.
The Pilobolus mycelium feeds on the dung pile and the cycle of life begins again.
An interesting fact about Pilobolus is that, although it does not cause any diseases, the larva of Dictyocaulus, a roundworm that causes lungworm in herbivorous animals, piggy-backs on the air-borne Pilobolus sporangia to also move away from the exhausted dung pile. This enables Dictyocaulus to also increase its chances of being ingested by a herbivore.
Help first graders understand that plants are alive because they breathe, eat and grow. Demonstrate that plants are alive by recording the growth in small houseplants.
Expose students to a variety of ideas about plants, such as planting a bean in soil to demonstrate the different stage of life in the plant, or placing carnations into colored water to demonstrate how plants suck up the water through the stem.
Demonstrate the different parts of a plant with different produce. Show how a carrot is the root of the plant, how celery is the stem of the plant, lettuce is the leaf of a plant, oranges are the fruit of the plant and how apples contain seeds.
Seeds, spores and cones are important to plants because this is how plants reproduce. Seeds are found in flowering plants and house a dormant plant embryo. Cones are the reproductive parts of coniferous trees. Spores are the reproductive parts of nonflowering plants like ferns and mosses.
Prepare the soil as you would for any new lawn, which includes tilling the soil some 4 to 5 inches deep, removing root clods and stones, enriching with several inches of peat moss, compressing with a roller, raking to smooth and leveling the area.
Water the soil prior to planting to moisten it. The soil should be moist, not soaking.
Lay the runners on the soil with the node or root side on the soil. Space the runners 1 to 2 feet apart.
Run a stolon roller over the runners to press them into the soil. You can rent a stolon roller from an equipment rental center, and follow the manufacturer’s operating instructions.
Cover with a layer of straw mulch, approximately 1/2 inch deep, to retain moisture. And make sure to keep the soil moist.
Seeds are the product of sexual or asexual reproduction in plants. They grow in ovaries or fruits as the result of fertilization, often with the help of insects such as bees or birds such as hummingbirds.
The primary function of seeds is the continuation of the species. This is especially important for annual plants that do not reproduce easily by division.
The earliest land plants propagated by means of spores--single-celled reproductive bodies. As plants became more diverse and complex, seeds evolved, first as soft-sided seeds on gymnosperms and then as the hard-coated angiosperm seed, with embryo and food supply.
Seed production provides an opportunity for a species to improve itself by hybridization. Pollen from another species is used to fertilize an egg and the seed that develops will contain an embryo of an improved or stronger new species.
As long as the plant works on producing seed or blooms or fruits are removed, the plant will continue to work, growing ever less vital. The maturation of seeds provides signals to the plant that the end is near and to begin the process of dying back so seeds can mature and fall.
Reproduction by Seed
Gingko trees develop seeds in two ways. Male gingko trees grow long catkins and seed nuts while female gingkos flower and then form seed nuts. Gingko seeds resemble outsize pistachios in a half-cracked shell. Growing gingko by seed is a simple but a very slow process as gingko only produces flowers and seeds when the tree reaches roughly 20 years of age.
Most commercial gingko trees available on the market today are male gingko tree stock cuttings top grafted onto seedlings of hearty, compatible root stock. Male grafting stock is used to almost exclusively avoid the messy and foul-smelling fruiting that occurs with the mature female gingko tree.
The balsam tree, Abies balsamea, propagates via seed or by natural layering. Natural layering can occur when low branches get into soft, wet earth.
Remove any dead or diseased branches, whether growing upright or along the ground.
Use a garden rake to rake the runners not yet rooted along their length so they all face one direction.
Trim off one-third of the length of the runners.
Cut back the upright branches by one-third of their height.
Reposition the runners. Any runners that are not yet rooted along their length should be repositioned so they are evenly spaced around the plant.