How to make a plant life cycle,stress free diet,meditation chicago classes - PDF Books

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Bryophyte ReproductionBryophytes are primitive plants that don’t have seeds or vascular systems. Budding botanists will love these flash cards that encourage science and curiosity about life cycles.
The plant life cycle starts out when a big plant opens it's seedpods and the wind carries the seeds away. Tip: To turn text into a link, highlight the text, then click on a page or file from the list above. Because they lack a mechanism for moving water through their bodies, bryophytes are pretty small. Let’s look at the structure of a flower to figure out where the pollen starts and where it ends up. The male bee is fooled into thinking that the flower is a female bee, and so he goes to mate with her. Have your child arrange the stages of plant life in numbered order, then help their little green thumbs glue the cards down. He inevitably picks up pollen from one flower and transfers it to the next flower he tries to mate with. These flash cards serve as an intro to life science, but also help with counting skills and sequential ordering.
Mosses, liverworts and other bryophytes are so tiny that it is easy to ignore them most of the time, even if they are under your feet. The four main parts of a flower are the:sepalspetalscarpelsstamensSepalsSepals help protect the flower bud before it opens, since they are often thicker than petals and can enclose the bud completely. Mosses actually are underfoot a lot—check out the cracks in the sidewalk and you’ll probably find moss there. In orchids, the sepals look just like the petals and can have complicated multi-color patterns.
Petals Petals are the eye-catching part of the flower, and come in every color of the rainbow. What really happens is that the sporophyte grows out of the top of the gametophyte, so it looks like a headdress of some kind.
In this image of stagshorn moss, the green leafy part is the gametophyte and the tall spindle on top is the sporophyte. Since they usually live in places that are moist at least some of the time, this isn’t really a problem for bryophytes.
This way, bees don’t waste their time looking for nectar in places where it has already been taken, and the flowers that haven’t been pollinated yet have a better chance of flagging down their pollinator. However, they still wait until a rainy period to reproduce, because they need water to carry sperm to the eggs.
Image from here.CarpelsThe carpels, which are collectively called the pistil, are the female reproductive parts. Asexual reproduction occurs when a sporophyte releases spores, and sexual reproduction happens when gametes fuse and form a zygote.When a bryophyte spore settles somewhere, it grows into a gametophyte.

On top of the ovary is a stem-like thing called the style, and the stigma, which is sticky and receives the pollen.
The pollen is contained on the tip of the stamen, which is called the anther; it sticks up like an antler on a deer or moose. As Rihanna says, when it’s raining more than ever, the eggs stay under the umbrella; meanwhile the sperm take a free ride on the rainwater and seek out eggs. In the liverwort Marchantia polymorpha, the antheridia look like umbrellas:After sperm and egg join in fertilization, the zygote grows into a sporophyte.
In the anther, microspores divide and develop into male gametophytes, but the male gametophyte is only two cells.
This is still happening on the gametophyte, which makes the sporophyte generation completely dependent on the gametophyte generation.
The other cell, the tube cell, produces the pollen tube that sperm travel down to reach the female gametophyte. FertilizationPlant reproduction is pretty complicated, with a lot of steps, so it’s easy to understand why plants would enlist the help of other unsuspecting organisms.
The gametophytes release sperm to fertilize eggs, and fertilization happens right on top of the gametophyte. Pollen is found on the anthers.Once the pollen grain lands on (or is brought to) a receptive stigma, a pollen tube starts to form from the tube cell. The sporophyte grows into a new fern plant, and produces spores to complete the life cycle. A few things make this simple story a little more complicated: Spores are produced in a sporangium (plural = sporangia). Sporophytes are diploid (2N), but since they produce spores through meiosis, spores are haploid (N). Sporangia occur on the underside of fern fronds in little clusters called sori (singular = sorus). Image from here.The densely packed brown dots are sori, clusters of spores underneath fern leaves. Gymnosperm ReproductionGymnosperm means "naked seed," a name that reflects the fact that gymnosperms have no fruits to protect their seeds. However, the presence of seeds isn’t the only thing that separates gymnosperms from ferns; a lot of changes happened along the way in the evolution of seed plants. These changes include:the seedreduced gametophytesheterosporyovulespollen grainsFirst, the seed. A seed has the potential to grow into a new plant, but isn’t considered a separate plant until it disperses and germinates. Because a seed has a protective coating in the form of a seed coat, it can lie dormant for months or years until conditions are right for it to germinate. Spores don’t enjoy the same relaxed schedule as seeds because they are usually made of only one cell, with no protective coating.
In ferns, the gametophytes lived on their own, were photosynthetic, and were small compared to the sporophyte.

They aren’t photosynthetic and don’t live on their own: instead, gametophytes live on the sporophyte. There are also two kinds of gametophytes, bringing us to the next subject…Heterospory: In seed plants, there is no one-size-fits-all spore. Instead, there are megaspores, which grow into female gametophytes, and microspores, which grow into male gametophytes.
Each sporangium makes only one kind of spore, so the sporangia are either megasporangia or microsporangia. And because not every gymnosperm is a pine, we also find sporangia on cones of other species, such as firs, redwoods, and spruces. You probably have spent much more of your life thinking about ice cream cones and sno-cones than plant cones. Pinecones aren’t as tasty as frozen sweets, but have very important jobs to do, so we can’t blame them too much.
The technical name for plant cones is strobili (sounds like a type of pasta, doesn’t it?), and they are the site of all the sporangia.
Male cones are temporary structures that exist only long enough to make and release pollen, but female cones can grow for years while the seeds they hold develop. Ovules: As we already established, a megasporangium produces a megaspore, and they are stuck on a spore-bearing leaf (a sporophyll) on the sporophyte.
Pollen grains: Once the microsporangium produces a microspore, that microspore develops into a pollen grain that consists of a male gametophyte and a tough pollen wall that protects the gametophyte while the pollen grain disperses. If you get seasonal allergies, you can probably blame your runny nose and itchy eyes on the wind-pollinated plants that release their pollen into the air and straight into your nasal passages. Just tell those plants that they would be better off finding animal pollinators and to leave you alone! Instead, the pollen is picked up, usually by a flying animal such as a bee, bird or bat (the pollinator), and gets transferred from plant to plant as the pollinator looks for nectar, which is a sugary liquid flowers secrete. In the process of drinking delicious sweet nectar from flowers, the pollinator inadvertently carries pollen from one plant to another.
Yummy!SourcePlants that rely on animal pollinators are more successful than plants that use wind or water to transfer genetic material: this is why so many angiosperms have evolved and prospered.
Even though angiosperms have fancy fruits and flowers, they still have gametophytes, gametes, spores and sporophytes. The angiosperm life cycle looks like this:If you can ignore the flower for the moment, you’ll notice that on the sides of the diagram, a spore is just developing into a gametophyte, which makes gametes.
On the right side is the microspore, which is the male side of things, and on the left side is the megaspore, holding down the female camp.

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