Thursday, October 11, 2007

Plants Part II

In Greek Angiosperm means "enclosed seed".
Angiosperms are the most complex, efficient and colorful out of all of the plants
Unlike the other plants Angiosperms protect their embryo with a hard outer coating.
Angiosperms are flowers, and fruit.
4 parts of a flower
Petals- Surround the reproductive organs. Often brightly colored to attract insects.
Sepals- Surround and protect the flower bud. They serve as an extra protection in between the petal divisions.
Stamens- The male organ of a flower which contains pollen.Pollen contains male gametes, which fertilize the carpels in other flowers. Adaptations such as prevention of self pollination have increased diversity and have allowed for more change.
Carpel-Female organ of a flower which contains the stigma,style and the ovary.
Flower Variations
There are over 250,000 species of flowering plants.
There are so many different variations. Variations attract different pollinators.
Yellows, reds and blues attract bees.
White with a nice scent attract bats.
This clip shows bees going into a flower and feeding on its sweet nectar.
Not only are the bees benefiting off this flower, but the flower is benefiting off them too. While these bees are feasting they are getting pollen(male gametes) all over their coat now when they go to the next flower the gametes will go into the carpel and fertilize the egg of another flower.Another interpertation maybe that these bees have already feasted and now are just getting a snack plus fertilizing this flowers egg. This is a symbiotic relationship(mutually benneficial).Because of the insects/animals plants do not have to make as much pollen because they provide a more direct and efficient way for fertilization.
If its got seeds its a fruit
Fruits spread and protect seeds.
The next generation is in that seed.
There are two classes of Angeosperms. This depends on the number of cotyledons an Angiosperm has.
Cotyledon- the first leaf or leaves of a seedling.
Seedling- A young plant developing out of a plant embryo of a seed.
These are found in all fruits but some may contain one cotyledon(seed leaf)
and others contain two.
Monocot- one cotyledon seed leaf
Dicot- two cotyledon seed leaves
Monocots Vs. Dicots
Monocots Dicots
Embryos with a single cotyledon Embryos with two cotyledons
Floral parts in threes Floral parts in fours or fives
Parallel leaf vains Net like leaf veins
pollen grains has one pore or furrow Pollen grains has three pores or furrows
Vascular bundles throughout stem's Stem vascular bundles arranged in a ring
ground tissue Examples are (woody plants,trees
Examples are (grasses, palms and and beans)

Just something ammusing

1 comment:

MikeM said...


What makes it an animal?

Animals ARE animals because they don't have a cell wall, are multicellular and are heterotrophic. There are animal-like protists but they are single cellular so they get tossed back into that "junk drawer" kingdom.

The seperation of animals
That little aforementioned protist is actually the likely ancestor of all animals. What may have happened was the grouping of these protists into one colony (which is proven in the sponges, which have many cells that look like similar protists). They have NO symmetry at all.

Second in line would be the development of tissues. Not saying protists began using kleenex, but became soft bodied, moving organisms. The hydra is a good example of this very simple, organless, predator. They use on hole as a mouth and anus....efficient, yet gross. They also have radial symmetry, which means they can be cut in any straight line from a top view and both halves will look the same.

These organisms show the first evidence of a digestive tract. That means these little flatworms actually have a SEPERATE mouth and anus. They also show bilateral as opposed to radial symmetry. For the most part, platyhelminthes are parasitic, so they cant find their own food... they rely on other organisms.

Very similar to platyhelminthes in just about every way. How ever the difference between them is a very critical one. They have a tissue layer to seperate the digestive tract from the rest of its body. They are still parastic and still have bilateral symmetry.

Moving right along in the animal kingdom is the classification of mollusca. These are soft bodied organisms that ,mostly, produce a hard outer shell for production. The exception to this is the octopus. They still have a digestive tract seperated from the rest of the inside of the body. Gives their food a pretty straight run.

The third, and final, grouping of worms. These are segmented worms because they have the entirely seperate digestive tract that was lacking in earlier worms. Otherwise they are still very similar.

This is undoubtedly the most succesful phylum. There is much variation between organisms in it which allow them to live in very diffrent regions of the world. It houses crustaceans and insects and arachnids (oh my!). They are the earliest examples of jointed appendages. They have a hard exoskeleton, which is a huge first. I'd have to agree with Haldane, that if there is a creator, he did indeed have "an inordinate fondness for beetles."
Spiders have two body parts and eight legs, crustaceans have gills and antennae , and insects have 3 body parts and 6 legs.

A return to radial symmetry, like the cnidarians. However unlike the Cnidarians, they have an exoskeleton. As the name echinoderm(which is greek for "spiny skin") implies, they have.... well...spiny skin.

Structure supported by internal skeleton made of cartilige/bone. They have a two chambered heart that runs on a single loop. This doesn't allow them to produce enough energy to be warmblooded (endothermic) so they are coldblooded(ectotermic). But just because they have half the heart doesn't mean they have half the love. Fish reproduce externally using an aquatic egg. The female often releases hundreds (for some species thousands) of eggs at a time to be fertilized.

Land Ho! Amphibians have legs that allow them to live outside of water. How ever, they must keep their skin moist to allow gas exchange, and also rely on water for reproduction. They also lay aquatic eggs. So they still live relatively close to water. They have a three-chambered heart which is still not quite cutting it, so they too are ectothermic. They push air into their lungs, which is called positive pressure.

Internal fertilization of a hard shelled, solid egg as opposed to previous aquatic eggs allows them to move further from water. Still have only a three chambered heart and therefore are still cold-blooded ectothems. However, they take in air through negative pressure, which is the same method we use.

Very light, pourous bones to allow for flight. They have feathers covering their body. They have very efficient lungs and multiple "air sacs" to help them stay afloat much easier. Most importantly, they have the four-chambered heart which can produce the energy required for flight. It also produces enough energy to allow them to be warm-blooded (endothermic). Reproduction is much like reptiles, internal fertilization, then a hard, amniotic egg is layed.

Also have a four-chambered heart allowing them to produce their own heat, being endothermic. Humans are under this phylum. For the most part mammals reproduce through internal fertilization and internal development. All mammals fertilize internally however, have diffrent cycles after fertilization occurs. Monotremes are mammals that lay eggs, such as the echidna. Marsupials develop their young in a pouch with a short-living placenta. Then placental mammals fully develop internally and have a "true placenta" which allows the fetus to get nutrients and get rid of wastes.