Monday, August 31, 2009

Gymnosperm Cone

Picture 13 - This is a picture of a gymnosperm cone. This cone is a ovulate cone to be specific and is a female cone. It produces seeds and are typically produced on the upper branches of the same tree that produced male cones, and their scales become woody.


Picture 14 - This is a picture of a pollen bearing cone. It is a male gymnosperm cone and it releases pollen that hopefully gets picked up by the wind and disperses it among the female cones.

Gymnosperm Leaf

Picture 11 - This is a picture of a pine tree's leaves. Notice the needle like shape of the leaves. This is what makes it a gymnosperm leaf. There are four groups of living gymnosperms. Conifers, cycads, gnetophytes, and Ginkgo. All these groups lack the flowers and fruits of angiosperms. In all of them, the ovule, which becomes a seed, rests exposed on a scale and is not completely enclosed by sporophyte tissues at the time of pollination. This pine is a conifer and has tough needlelike leaves produced mostly in clusters of two to five.


Picture 12 - This is another picture of a pine tree. The species of this pine is different than the one I posted right above it. Now to further describe pines...The leaves, which have a thick cuticle and recessed stomata, represent an evolutionary adaptation for slowing down water loss.

Frond

Picture 9 - This is a picture of a fern. Ferns are the most adundant group of seedless vascular plants, with about 11,000 living species. Recent research indicates that they may be the closest relatives to the seed plants. The leaves are referred to as fronds and usually develop at the tip of the rhizome which is a horizontal underground stem with roots emerging from the sides, as tightly rolled up coils.

Picture 10 - This is a picture of another fern hanging over a local pond. This is another example of a frond. Fronds are highly dissected and feathery.




Meristem

Picture 7 - This is a picture of a flower about to bloom. On the sides of the already bloomed flower, two flowers about to bloom are shown. Plants develop by building their bodies outward, creating new parts from special groups of self renewing cells called meristems. As you can see, the two new blooming flowers and jutting out of the already bloomed flower in their effort to grow and develop.

Picture 8 - In this picture is another flower about to bloom. In the center is the flower I'm talking about. This picture was taken in a nearby park. First, the plant grows through early cell division, tissue formation, seed formation, and then meristematic development and morphogenesis. The leaves of the flower have grown and the flower is trying to bloom.

Population

Picture 5 - This is a picture of pine trees. Individual organisms are ogranized into several hierarchicallevels within the living world. The most basic of these is population. This is when a group of organism of the same species live in the same place. This population of pine trees was found in a park outside my aunt's home.


Picture 6 - This is a picture of lilypads. Because it is gathered together like this and it belongs to the same species, it can be called a population of lilypads. This picture was taken by a pond by my aunt's home.

Exoskeleton

Picture 3 - This is a picture of beetles. Exoskeletons surround the body as a rigid, hard case. Arthropods, such as crustaceans and insects, have exoskeletons made of the polysaccharide chitin. An exoskeleton offers great protection to internal organs, resists bending, and provides attachment sites for muscles. However, in order for the arthropod to grow, it must molt and shed its old exoskeleton. During this period, arthropods are vulnerable. Exoskeletons also limit the growth of the arthropod. If these beetles grew to the size of humans, the weight and thickness of the exoskeleton would prevent movement.


Picture 4 - This is the picture of crabs. These crabs are crustaceans that were found along the shore during my stay in Korea. As you can see these crabs are fairly small, showing that the exoskeleton does keep arthropods to a certain size. These crabs were also very quick. Although these crabs are small, because their exoskeleton is also lighter and thinner, it allows for this quick movement.

Ectotherm


Picture 1 - This is a picture of goldfish. These goldfish are ectothermic. This means that they receive their heat from external scources. In addition, homeothermic animals have a constant body temperature and poikilothermic animals have a body temperature that fluctuates with ambient temperature. Reptiles are largely ectothermic poikilotherms.

Picture 2 - This is a picture of an amphibian. This amphibian was found by the shore during my stay in Korea. Just as the goldfish, this amphibian receives its heat from external scources as well, and is a poikilothermic animal that has a body temperature that is largely determined by its surroundings, and fluctuates.