Unit 9 Reflection

In this unit we learned about taxonomy and how organisms are classified into their kingdoms, phyla, and classes. The more closely related organisms are, the more close they are classified. We looked at the tree of life a lot, and how it shows evolutionary relationships. It also shows where and when species became reproductively  isolated and that shows why organisms have the features they do today. Organisms are divided into domains, kingdoms, phyla, classes, orders, families, genuses, and finally species. This classification helps scientists organize species. They also use cladograms, which show evolutionary relationships and traits.

There are three Domains in the three domain system. Eukaryota, Bacteria and Archaea. Archaea are like bacteria but certain traits cause them to be in a separate domain. They live in some of the most harsh environments on earth, often without oxygen. Bacteria are also single celled and have no nucleus. They are in two kingdoms, gram-positive and gram-negative. Viruses are technically not living but some theorize that they are the origin of life on this planet.

The Domain Eukaryota contains the kingdoms protists, plantae, animalia, and fungi. All eukaryotic cells have a nucleus. Protists are organisms that are hard to classify, and therefore it is the most diverse kingdom. Plantae is all plants, including vascular and non-vascular plants. Plants do photosynthesis to create energy for themselves. Fungi are very different from plants. They are heterotrophic, and one of the main decomposers. They have cell walls that are made of chitin and can reproduce sexually or asexually. The typed of fungi are bread molds, sac fungi, and club fungi.

The Domain Animalia contains all animals. 97% of animals do not have a backbone. The most primative animal is the sponge. Cnidarians are similar but are more complex and have tissue. Flatworms can move around but do not have a complete digestive tract. Mollusks have a digestive tract and a respiratory system. Arthoropods include insects, and have a exoskeleton. Crustaceans are similar to arthropods but in the water. Echinodermata have a water vascular system that can allow them to move.

Vertibrates make up the rest of the animal kingdom. All vertibrates are part of the phylum chordata. Agnatha were the first vertibrates and were jawless fish. Condricthyes are fish that have a jaw and cartilage skeleton. Osteicythes have jaws and bony skeletons. Amphibians are the transitionary class because they could live in water and land. The tiktallic was a trainsitional species that could get out of water and climb on land. This was a big breakthrough, because it allowed other species to evlolve to live on land.

Reptiles are ectothermic, cold blooded, and have 3 chambered hearts. Aves, or birds, have hollow bones and feathers. Mammals are endothermic and have complex reproductive and behavioral traits. Humans are mammals and have millions of years of ancestry and evolution to have the traits we have today.


There were no hard or complex concepts in this unit, only lots of content. There are a lot of phyla with certain characteristics to remember. Some questions I have are how do species develop new traits and even organs? How many more species are out there that we have not yet discovered? What species will take over once humans go extinct?

I think my presentation on the banana went pretty good. One thing I did not take into account was that I would speak faster in the presentation compared to practice, and therefore my presentation was a little bit short. I wanted to make eye contact and engaging with the audience a priority in my presentation, as I found it very boring to watch other people stand in the front of the room and read off a screen. To make sure I did not do this, I looked at the screen for a second every time I changed a slide so I could see what was on it and speak to the class about it. Presenting is a useful skill to have, as selling an audience or convincing a directed audience to agree with you or support you is extremely valuable.