Unit 9 Reflection

This unit was all about the evolution of organisms on Earth. We learned how organisms are classified and how they all contributed to our world in one way or another. By watching "Your Inner Fish" videos and doing the What on Earth Evolved Project, we saw the history of many different organisms and how they were introduced onto planet Earth. We also learned about plants, fungi, invertebrates, and chordates, along with the importance of them. We first started the unit off by learning about how life is organized. We found that classification is the grouping of organisms based on their similarities, and we learned about taxonomy and binomial nomenclature. We were also taught the seven levels of classification. Listing it from largest to smallest, the order is Kingdom, Phylum, Class, Order, Family, Genus, and Species. I think that one of the themes/essential understandings of this unit was knowing that organisms are classified not only by their physical appearance, but also by their evolutionary descents. In the second vodcast we covered the many kingdoms and domains. We learned that the three domains are Bacteria, Archaea, and Eukarya and that the five different kingdoms are Monera (Prokaryotes), Protista, Plantae, Fungi, and Animalia. We found that protists are very diverse and can be either unicellular or multicellular. We saw that fungi can be both decomposers and heterotrophs, and plantae can either have or not have a vascular system. We also learned that there are many different types of plants such as gymnosperms, angiosperms, and many more.

         

After learning about domains, kingdoms, and the levels of classification, we were introduced to bacteria and viruses. Bacteria are unicellular prokaryotes and were Earth's first organisms. They come in a variety of different shapes with the three most common being spheres (cocci), rods (bacilli), and spirals. Bacteria is important in our lives because they recycle nutrients, fix nitrogen, and help in the field of biotechnology. Viruses are not cells, but actually a very small infectious particle consisting of nucleic acid enclosed in a protein coat and, in some cases, a membranous envelope. Some viruses have membranous envelopes that help them infect hosts called viral envelopes. Once a viral genome has entered a cell, the cell begins to manufacture viral proteins and use the host enzymes, ribosomes, tRNAs, amino acids, ATP, and other molecules. The reason why viruses make us sick is because they damage or kill cells by causing the release of hydrolytic enzymes from lysosomes.

         

Now that we were familiar with bacteria and viruses, we learned about plants and fungi. The first true plants probably grew at the edges of water and evolved through natural selection. Some plants have a vascular system allowing resources to move to parts of the plant, giving it a huge advantage. The major plant phyla are Bryophyta (mosses), Pterophyta (ferns), Gymnosperms (cone bearing plants), and Angiosperms (flowering plants). There are two major types of Angiosperms, monocots, which have a single seed leaf, and dicots, which have two seed leaves. Fungi, on the other hand, have completely different traits than plants. Their cell walls are made of chitin and they absorb their food through hyphae. Some types of fungi are sac fungi, bread molds, and club fungi. They are important because they can be eaten, used for antibiotics, and act as pathogens.

Finally, we learned about invertebrates and chordates. There are two types of symmetry in animals: bilateral and radial. Some phylums of invertebrates are molluska, cnidaria, and porifera (sponges). Some other examples of invertebrates are crustaceans, arthropods, and insects. Most organisms in the phylum chordates are vertebrates rather than invertebrates. The seven classes of vertebrates are agnatha, condricthyes, osteicthyes, amphibia, and the amniotes reptilia, aves, and mammalia. Reptiles and amphibians have three chambers in their hearts, while birds and mammals have four. They can either be endothermic (warm-blooded) or ectothermic (cold-blooded).

I want to learn more about how transitional organisms such as Tiktaalik and Archaeopteryx because they are the bridges between two completely different species. The "Your Inner Fish" videos really sparked my interest in how humans came to be. An unanswered question I have is are there any other transitional organisms that we haven't found out about yet? I also wonder about how the tallest and biggest animal, can have the same common ancestor as the smallest and tiniest animal.

The What on Earth Evolved Presentation was a huge part of this unit. I thought that the project went really well, and I really liked how we had the freedom to add in information that we thought we were important rather than have set guidelines. We had basic instructions, but we could really customize the presentation for our own creativity. I think that I presented really well and did a good job memorizing my presentation, but I think that I could have done a better job by putting less words on the slides so that the audience could be more focused on what I'm saying rather than my visual. I will definitely apply the skills I've learned from this project into my TED Talk. Next time I will make sure to have less on my visual so I can be the one leading the presentation.