Unit 9 Reflection

This unit, called “What on Earth Evolved” surrounded the essential questions “How is life organized?” and “What are the defining characteristics of different organisms?” Organisms are placed in groups based on similarities and this system of naming and classifying living things is called taxonomy. The taxonomic levels are, Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species. I made up a mnemonic device to remember this order, Dumb Kids Playing Cards On Freeways Get Smashed. I know it’s a little violent but it’s funny so it sticks. Whatever works, right? Here is the taxonomic classification of a modern human:

There are 3 domains, called Archaea, Bacteria, which has one kingdom called monera(prokaryotes), and Eukarya, made up of 4 kingdoms, Protista, Fungi, Plantae, and Animalia.  Bacteria are the oldest organisms and are decomposers, nitrogen fixers(using symbiosis), and are a key component in Biotech. Viruses are not cells but small infectious particles that use their capsids and membranous envelopes to capture host cells. Fungi are classified into 3 groups, sac-fungi, club-fungi, and bread molds. Plants are spread into 4 phyla, Bryophyta(mosses), Pterophyta(ferns), Gymnosperms(cone bearing plants), and Angiosperms(flowering plants). Within Angiosperms lie Monocots(single seeded), and Dicots(double seeded).

Next come the invertebrates, in which most have Hox genes that control early development. I was surprised that 97% of all animal species are invertebrates, and I wrote a blog post earlier about one interesting invertebrate. The most primitive invertebrate, sponges, are followed by cnidarians. Cnidarians have two forms, polyps and medusas and 4 major classes, scyphozoans(jellyfish), Anthozoans(coral), Hydrozoans(hydra), and Cubozoans(box jelly). Next, flatworms, mollusks, and annelids are closely related. Arthropods have a touch skeleton and echinoderms have a unique water vascular system.

The final group, chordates, are the vertebrates, which all have a back bone. There are seven classes of vertebrates Agnatha(jawless fish), Condrictheyes(Cartilaginous Fish), Amphibia, Reptilia, Aves, and Mammalia. Amphibians, Reptiles, Birds, and Mammals have amniotic eggs to allow them to reproduce on land.

To dive deeper into each of the categories throughout the unit, each student learnt about a species from the book “What on Earth Evolved” and presented about it to the class. My project was on the genus Australopithecus. I did not procrastinate as I usually do because I was trying out methods for my 20 time project (progress 3-28-16 and 4-18-16) and my topic is preventing procrastination. Even though I was prepared with the content, I was so nervous to speak to the class. I spoke really quickly and finished my slideshow barely in the time limit! I think in the future I would benefit if I presented to smaller audiences leading up to the final presentation to the class. I will try this out for my TED talk and focus on speaking slower. Even listening to my classmates was interesting because a new face and voice would teach us every 4 to 8 minutes.

To finish off the unit and tie in the vast amount of information we acquired over a short period of time, we watched a documentary called “Your Inner Fish”, where scientists proved that humans share common ancestry with fish and are related to reptiles. It was cool to see how our ears have evolved from the reptilian structure and how many of our limbs follow the universal “one bone, two bones many bones” pattern. People are still uncovering the mysteries surrounding the evolution of life today and there is so much more yet to uncover about this world.