The End....

Or is it???

I hope you've enjoyed reviewing with me for this year's CRCT. As you probably know, the test is tomorrow. Good luck, everyone!

-Jerome

(Keep in mind, this is not an actual blog of mine, although I may be making my own real one in the near future.)

Doctor's Report

(S7L2.e)

Doctor’s Report 

Doctor: Dr. Jerome D. Sipin 

December 12, 2013 12:15 PM 

Patient: Billy Bob Smith Jr. 

Age: 24 Gender: Male 

DOB: October 12, 1979 

Condition: Multiple sclerosis 

      Dear Mr. Smith, It has come to my attention that you have been diagnosed with multiple sclerosis. Last time you visited us, you showed the following symptoms:

  -Dizziness 

  -Numbness of the leg 

  -Blurred vision 

These are symptoms of multiple sclerosis. This disease affects the nervous system of your body, which controls your body. Multiple sclerosis causes the immune system to attack nerves, which damages the myelin coating of the nerve. The myelin allows nerves to transmit signals quickly and efficiently. Because of this, normal nerve activity can decrease. Organs affected by multiple sclerosis differ from person to person. Right now, for you, Mr. Smith, you’re looking at multiple sclerosis affecting your muscular system and sensory organs. Loss of vision is rare, and becoming paralyzed is rare as well. Overall, multiple sclerosis can make it harder for you to do even the simplest of things. 

As multiple sclerosis is a neurological disorder, it can affect just about every major organ in the body. The immune system attacks myelin, a fatty material coating nerves. This material helps the nerve transmit signals quickly and efficiently. Normal nerve activity decreases with the onset of multiple sclerosis. This is because multiple sclerosis causes scars to form on the covering of the nerve. This is where the name multiple sclerosis comes from, as it means “scars”. The organs affected by multiple sclerosis vary from person to person, as do the symptoms. For example, it can attack nerves leading to muscles, leading to loss of muscle control. 

Here’s how multiple sclerosis can affect the organs in these systems. Multiple sclerosis can affect all organ systems in the body. Multiple sclerosis can affect two major parts of the sensory system (which is part of the nervous system); vision and hearing (eye and ear). As explained before, you can get vision problems from multiple sclerosis and hearing problems. Deafness and blindness are very rare, and most cases in vision and hearing eventually solve themselves. The muscular system is affected when the brain has trouble communicating with the muscles. This can lead to numbness, hand-eye-coordination problems, and loss of motor skills. Problems start slowly and worsen as nerve damage increase. This can be treated through a wheelchair or another type of aid. Parts of the respiratory and digestive system are also affected. You can have trouble speaking, breathing, and even swallowing. People with MS also have a risk of getting osteoporosis because of treatments like steroids, and because of plain inactivity.

Sadly, there is no cure for multiple sclerosis at the moment. However, strategies like therapy, modifying the course of the disease, and treating attack areas can help. Some medications can ease the pain of MS attacks. Even steroids can help with victims of multiple sclerosis. By strengthening weakened muscles, steroids make a good medicine for people whose muscular system is attacked by multiple sclerosis.

Dichotomous Key

(S7L1.a)

A dichotomous key helps us identify what exactly an organism is. The reason they are called dichotomous is because the word "dichotomous" means "divided into two parts", hence the two choices you are given when using a key. They consist of a series of choices that lead the user to the correct organism.

To develop a dichotomous key, you need at least 4 organisms. The first 2 questions should be something that all organisms have in common. Next, you branch out depending on their characteristics. Soon, you have a dichotomous key!

Classification of Organisms
(S7L1.a)

Classification was the final thing we learned this year. It is the way scientists organize the living things on the planet. All organisms are given a two part scientific name along with their common name. Scientific names are written in italics. The first part is their genus (written with the first letter being capitalized), while the second part is their species, which is not capitalized (like the scientific name for humans: Homo sapiens).

Scientists also classify organisms into different kingdoms and domains. The 3 domain system uses eukarya, archaea, and bacteria. Eukarya is for eukaryotes, or organisms with more than 1 cell. They are usually very complex organisms. Archaea are bacteria that live in very unforgiving environments (such as in the Antarctic). Bacteria is your standard bacteria, the ones that live in your stomach, the ones that you colds, etc...

The 6 kingdom system uses animalia, plantae, fungi, protista, eubacteria, and archaebacteria. This is basically a more unorganized version of the 3 domain system. Animalia, plantae, fungi, and protists belong in the eukarya domain, while the kingdoms of archaeabacteria and eubacteria become their own domains (archaea and bacteria).

Organisms are also classified like this:
Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species. As you go down, the organisms become more and more in common.

Copyright: none of images are mine, I do not claim ownership of these images, I just found them on Google.

The Fossil Record

(S7L5.c)

(Plus, info about Half-Life 3!)

(And by that, I mean 3 half-lives)

The fossil record is why we know about the organisms that lived before us and how they changed. Species can often go thousands of years without change through evolution. With fossils, we can document change of these organisms. 

Sedimentary rock is the most common rock on the planet. Whether it's a coincidence or not, fossils also happen to be most common in sedimentary rock. These rocks also make it very easy for scientists to date generally. However, if a scientist wants to date a fossil more accurately, they must use half-lives. Suppose an element in a fossil has a half-life of 5,000 years. 15,000 years pass until it is found. That's 3 Half-Lives (pun defiantly intended).

3 Half-Lives

(Better known as: Half-Life 3 confirmed!)

(Copyright: the image of Half-Life 3 is not made by me, neither is the image of the Helix Fossil. [praise Helix!])

Evolution and Natural Selection
(S7L5.a and b)

Evolution is the theory that all organisms share a common ancestor and that we developed new features over time to help us survive. For evolution to occur, natural selection must occur, as well. A man by the name of Charles Darwin was one of the first to comprehend this theory. He studied the organisms on the Galapagos Islands, off the coast of Chile in South America. One thing he observed was how the finches on each of the different islands were adapted to different things, depending on the environment of the island.

Here's Darwin's own summary of natural selection (taken from his book "Origin of Species"):

If during the long course of ages and under varying conditions of life, organic beings vary at all in the several parts of their organisation, and I think this cannot be disputed; if there be, owing to the high geometrical powers of increase of each species, at some age, season, or year, a severe struggle for life, and this certainly cannot be disputed; then, considering the infinite complexity of the relations of all organic beings to each other and to their conditions of existence, causing an infinite diversity in structure, constitution, and habits, to be advantageous to them, I think it would be a most extraordinary fact if no variation ever had occurred useful to each being's own welfare, in the same way as so many variations have occurred useful to man. But, if variations useful to any organic being do occur, assuredly individuals thus characterized will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will tend to produce offspring similarly characterized. This principle of preservation, I have called, for the sake of brevity, Natural Selection.

Going back to evolution, evolution may be change over time, but it does not mean something like the leaves falling off trees, or mountains being eroded. Evolution is to change genetically. Over the millions of years life has existed on this planet, new species have emerged through evolution by becoming better adapted for their environment.

Take whales for example. Studies have shown that whales probably started off as an animal similar to a wolf. As they figured out it would be easier to hunt in water, their legs and tails became more suited to swimming over the generations. As they continued to evolve to the water, the prehistoric whales saw no need to be on the land, and thus, their legs became smaller over time, as they fully lived in the ocean.

Comparing and Contrasting Asexual and Sexual Reproduction
(S7L3.b)

Contrasting:
-Sexual reproduction requires 2 parents
-Asexual reproduction only needs a single parent
-Sexual reproduction produces an offspring with traits of both parents, allowing for natural selection
-Asexual reproduction produces an offspring EXACTLY like the parent

Compare:
-Both produce offspring
-Both involve reproduction at cellular level