Unit 9 Reflection

 This unit is all about what on Earth evolved. We learned about how organisms from a long time ago have evolved into humans and other plants and animals today. In the beginning stages of this unit, we were introduced to the study of classification, also known as taxonomy. We learned about the taxonomic levels, which are(from biggest to smallest): domain, kingdom, class, order, family, genus and species. As you go down the ladder of classification, you find that the organisms that belong to the species have more in common then the organisms in the same genus. Next, we learned about bacteria and viruses. The importance of bacteria is that they are decomposers, the are nitrogen fixers and they are apart of biotechnology. Viruses on the others hand are bad for us. They usually make us sick with diseases, like HIV or AIDS. After learning about the viruses and bacteria, we moved on to fungi and plants. Fungi can act as food, antibiotics, pathogens, and more. Fungi are very important to the ecosystem as they are one of the main decomposers in any ecosystem. There are many different types of plants. We learned about the 4 major phyla of plants, which are Bryophyta(mosses), Pterophyta(ferns), Angiosperms(Flowering Plants), and Gymnosperms(Cone bearing plants). All these new phyla help us understand the evolution of plants, as the first true plants probably grew at the edges of water.

Finally we reached the invertebrates and the chordates. The invertebrates include sponges, cnidarian, flatworms, mollusks annelid, arthropods, insects, crustacean and echinoderms. Sponges date back to 570 million years ago. They are sessile, have no symmetry and reproduce asexually and sexually. Cnidarians are the oldest existing animal group that have specialized tissues. The phylum Cnidarian includes jellyfish, sea anemones, coral, hydra and the box jelly. Flatworms have a solid body and incomplete or absent gut. Mollusks have bilateral symmetry and a complete digestive system. Annelids have segmented bodies and a fluid filled space completely surrounded by muscle. Arthropods have an exoskeleton made of chitin, joint appendages and segmented body parts. Arthropods can be classified into five groups which are: trilobites=extinct, bottom feeders, crustaceans=live in oceans and land, freshwater streams, chelicerates=specialized dagger like mouthparts, insects=live on land, must have six legs, myriapods=long bodies and many pairs of legs. They also have an open circulatory system, sensory organs such as an antennae,  body segmentation and compound eyes. Insects have a head, thorax and abdomen. They reproduce through a process called metamorphosis. Crustaceans have a cephalothorax and an abdomen, one pair of appendages per segment, two pairs of antennae, exoskeleton and carapace. Echinoderms have an internal skeleton made of interlocking calcite honeycomb. They also have a water vascular system which are a series of water-filled canals around the central disk. These canals store water used for circulation and movement. They also have a complete digestive system and they can regenerate their limbs.

The chordates include fish( condricthyes, ostreicthyes, lobe-finned fish), and amphibians, reptiles and mammals. Fish are vertebrates with gills and paired fins. Condricthyes are fish with skeleton made out of cartilage. The must move in order to breath. These type of fish include ratfish, sharks, rays, and skates. Osteicthyes are bony fish which have skeletons made out of bone. Their operculum protects their gills and the movements of this help the bony fish move water over gills. Lobe-finned fish are paired pectoral and pelvic fins that are round in shape and supported by a single bone. Amphibians are the first animals with 4 limbs. Tetrapods are vertebrates with 4 limbs, they can live on land or water, mobile muscular tongue and lay eggs in water, moist ground or leaves. Reptiles are ectotherms and they have dry scales, a 3 chambered heart and cloaca. The reptiles include turtles, tortoises and terrapins. There is also the birds. These animals evolved from the tetrapod, and have hollow bones, fused collarbones that form v-shape wishbone, rearranged muscles in legs and hips, and feathers. Mammals are the last chordate. This chordate has a large brain and is a endotherm with a complex social feeding and reproductive behavior. They have hair to retain heat and a four chambered heart.

Some things that I would like to learn more about is about how bacteria and viruses because we did not really go as in depth as we did with chordates and invertebrates.

This unit we did a presentation with the topic of "What on Earth Evolved?"My topic was the rubber tree. I think that my presentation went pretty well. Some things that I did well on was that I had enough information so I could fulfill the time requirement while informing my classmates what the rubber tree is used for. One thing that I could work on is reviewing more of the history involved with the rubber tree. The biggest part that I learned from this is in order to have confidence is to know your topic well. The more you know about your topic, the more confidence you will have.