Arthropoda

Arthropoda is the largest phylum in the world. Should all of these creatures really be classified together under one group? Why or why not? What do they all have in common? Cite some facts or examples to support your point of view.

I believe that all of the creatures currently classified as arthropods should continue to be under one phylum. As long as it makes sense to do so, it makes sense to do so, right? The five things that make an arthropod an arthropod are:

-An Exoskeleton

Meaning they’re invertabrae. Their skeleton is on the outside.

-Segmented Bodies

Segmented both inside and out.

-Jointed Appendages

As in limbs.

-Bilateral Symmetry

Divided vertically in two mirror images.

-Open Circulatory System

Blood is pumped through spaces called sinuses to reach tissue.

Sources: http://animals.pawnation.com/5-characteristics-arthropod-5177.html

http://www.ucmp.berkeley.edu/arthropoda/arthropoda.html

Prokaryote Excitement

“Many biologists are passionately fascinated by prokaryotes, the same way a “normal” person might be excited about sports, music, or some other hobby. What are some of the characteristics that get scientists so excited about these tiny, primitive creatures? How do you feel about them?”

To quote Wikipedia, ‘A prokaryote is a single-celled organism that lacks a membrane-bound nucleus, mitochondria, or any other membrane-bound organelles.’ The four basic shapes of a prokaryote are, Cocci (sphere shaped), Bacilli (rod shaped), Spirochaete (spiral shaped), and Vibrio (comma shaped). They usually reproduce by binary fission.

Source: http://en.wikipedia.org/wiki/Prokaryote

Prokaryotes don’t necessarily excite me, but they do interest me. It’s interesting to compare them with eukaryotes, and (non-scientifically) it could actually befun to draw their shapes, or put them together for an abstarct piece. But that’s just me.

On the Healing of Scrapes

Imagine you’re going for a walk-or a jog, depending on how energetic you currently feel. Now imagine that you trip over something; say, uneven ground, or your shoelaces. (Or even a giant piece of cheese, because, hey! it’s imaginary.) Whatever you choose to trip over, let’s say that when you fall, you scrape your knee.

What do you do?

Well, chances are, you reach for a band-aid. Or if you’re trying to look tough, you just get up and keep walking, ignoring the scrape. (Or if someone was watching you, you try to pretend that you never fell, because, let’s be honest, falling is embarrassing.)

But what do your CELLS do?

A lot. First, blood cells tighten, to prevent blood from escaping out the new ‘door’ in your skin. Then, platelets and clotting proteins join together to make a plug, which eventually becomes a scab. Then, white blood cells arrive to take care of any bacteria that entered the body. Next, skin gradually begins forming under the scab, until the wound is fully healed.

Now guess what would happen if your cells did nothing. Go on, guess.

That’s right. You’d DIE. (Thank goodness for the many functions of cells!)

Source: http://goaskalice.columbia.edu/how-do-wounds-cuts-scrapes-lacerations-heal