Friday, August 31, 2012

Kelsey McKean Photos 25-40

Seed Dispersal by Water- the movement of seeds away from the parent plant. Plants that grow either in or nearby the water disperse their seeds, and then the seeds get transported all around by the water, like here in Mount Rainier.

Exoskeleton- a rigid external covering for the body in some invertebrate animals, providing both support and protection. A cricket has an exoskeleton. 

Heterotrophs- an organism deriving its nutritional requirements from complex organic substances. An example of a heterotroph is a pig.
Radial Symmetry- symmetry around a central axis. An example of an organism with radial symmetry is a tulip flower. Radial symmetry allows organisms to reach out in all directions.

CAM (Crassulacean Acid Metabolism) Plant- The stomata in the leaves remain shut during the day to reduce evapotranspiration but open at night to collect carbon dioxide. The carbon dioxide is stored and then used during photosynthesis during the day. A pineapple is a CAM plant. 

Niche- a position or role taken by a kind of organism within its community. A flower in a backyard absorbs light, water and nutrients for photosynthesis, and provides food and shelter for other organisms.

Modified Leaf of a Plant- a normal leaf that that is adapted for special purposes. In a cactus, the leaves are reduced to thorns to reduce the rate of transportation to save water.

Eukaryote- an organism consisting of a cell or cells in which the genetic material is DNA in the form of chromosomes contained within a distinct nucleus, including all living organisms other than eubacteria and archaebacteria.

Ectotherm- an animal that is dependent on external sources of body heat. Fish are ectotherms because they are cold blooded.

Mutualism- symbiosis that is beneficial to both organisms involved. An example of mutualism is the relationship between a bee and flowers.

Homologous Structures- structures derived from a common ancestor or same evolutionary or developmental origin. The forelimbs of humans and bats are homologous structures.

Gymnosperm Cone- gymnosperms are a group of seed-producing plants such as conifers, cycads, Ginkgo, and Gnetales. An example of a gymnosperm cone is a pine cone.

Autotroph- an organism that is able to form nutritional organic substances from single inorganic substances such as carbon dioxide. Grass is an autotroph.

Cambium- a cellular plant tissue for which phloem, xylem, or cork grows by division, resulting in secondary thickening, located in the secondary meristems. In a tree stump, the cork cambium is near the outer ring.

Glycogen- a substance deposited in bodily tissues as a store of carbohydrates. A food that is a good source of glycogen is chicken.

Genetic Variation Within a Population- genetic variation is variation of alleles in genes, and occurs both within and among populations. Genetic variation is important because it provides the raw material for natural selection. My cats are a good examples of genetic variation, because they both clearly have different genetics.

1 comment:

  1. what happens when thee seeds that are dispersed by water are drowned or cannot grow because they are too close to the shore?