WW-P 9-12 Schools

Grades 9-12

A sporophyte is a phase in the alternation of generations where it produces spores through the process of meiosis which then mature into gamteophytes. These gametophytes then produces male and female gametes which through the process of fusion, produce a diploid zygote. This zygote further develops into a new sporophytes thereby starting the cycle again. The moss seen below on the ground as well as the tree is in its asexual phase and is a sporophyte.

A modified stem of a plant is a modification of the conventional stem, primarily for storage. There are various kinds of modified stems such as bulbs, buds, tubers etc. A tuber is one of the more common modified stems usually seen in potatoes. They are swollen, underground large structures that are not only for storage of nutrients but also for the process of reproduction. 

A modified root is usually used for storage of nutrients and water. An example of such a plant is the carrot, who's edible portion is the "tap root" of the plant. The tap root is used as a large underground structure for storing nutrients and water retrieved from the surrounding soil. 

Epithelial Tissue or Epithelium is one of the several tissue that comprise the skin. The epithelium contains many of the glands of the body and line the various cavities throughout the surface of the body. The example in the picture below is that of a snake shedding its skin or the epidermis, the outer layer of the epithelium. 

Analogous Structures refer to the alike structures of two different organisms that do not share the same ancestor. The example in the picture below is that of the wings of a bird that are alike to the wings of a fly.

Frond is the term for a large divided leaf usually seen in ferns. The examples below in the pictures are those of fronds of different kinds.

Every organism plays a certain role in the environment and always has an effect on it. Keystone species are those organisms that maintain the ecological balance affecting many organisms and determining their numbers in that specific area. An example of such a species is the Jaguar, a predator, that has a varied diet and helps maintain the population of its prey and other organisms. (Special item - key is very blurry in this picture and is the silver blur on the top)

In the process of cross-pollination, the pollen is transferred through air, water, gravity and organism. This organism is known as a pollinator that travels to various plants collects the pollen (unintentionally) and delivers them to various other plants. The pollinators are usually ants, bees, insects etc. The example int he picture below is a bee in the process of cross pollination.

"Homo" means same or alike and hence Homologous Structures refers to the organs in various animals or birds that are alike but serve a different function and are possibly formed differently. This is due to the fact that such organisms have the same ancestors but underwent evolution and mutated differently. The example is the wings of a bat that are the same as the forearms of humans which have the same skeletal makeup but have a different form and function.

Homeostasis refers to the regulation of the internal environment of an organism to survive in extreme and moderate conditions. Thermoregulation is one of the more common types of homeostasis where the plant or animal regulates the internal temperature. An example of this are bears that contain fur that help them get through winters and provide them warmth. The polar bear especially has a thick coat of fur that allow them to survive in Antarctica and very frigid conditions.