Mitosis and Meiosis

During our last class, we did a lab where we had to look at either an onion cell or an animal cell and find the different phases of mitosis using a microscope. My partner and I had the onion cell. We observed the cell using the microscope we were given and were able to find Interphase, Prophase, Metaphase, Anaphase, and Telophase. We also had to draw what the phase looked like. Later we were given a lecture about mitosis/meiosis. Below is a picture of the cell cycle going through G1 (growth), S (DNA Synthesis), G2 (double check), and mitosis...

Embryology, Gene Layers, and DNA Control

 Embryology...what is it? Well, Embryology is a science (obviously) that is based on the development of an embryo from fertilization. As you can see in the image above, in the very first of all our embryonic stages, we look very similar, almost identical. 

Within this development, there are three germ layers. These layers are known as endoderm, mesoderm, and ectoderm, endoderm being the innermost layer. The endoderm consists at first of flattened cells, and it develops the digestive organs and lungs. 


Mesoderm is the middle germ layer and it is best known for helping develop the muscles, skeleton, and blood system. This layer appears in the third week of embryonic development and is formed through a process called gastrulation. 


The third layer, or the exterior layer, is called ectoderm. It emerges and originates from the outer layer of germ cells. The word "ectoderm" literally means "outside" and "skin" in Greek. Go figure! Anyway, this layer helps form the nervous system. In other words, it forms the spine, peripheral nerves and brain. It also helps form the lining of mouth, anus, nostrils, sweat glands, hair and nails.


In embryology and the development of embryos, DNA interactions help control and show how genes operate. It also opens the information of their network control within the genes.

Animal and Plant cells

We started the class of by getting out Unit 4 tests back...not too bad. Then, because our entire class didn't actually read what we were supposed to for homework (oops!), we discussed with a partner the differences and similarities of a plant and animal cell. We did this by making Venn diagrams. This brought us into discussion about our Unit 5 project and we were then given time to work on it.

After working on the project for a little bit, we learned how to use a new type of microscope. We observed  a dog flea, a cheek cell from our cheek, and a plant cell. We looked so closely that we could actually see the cell walls and chloroplasts in the plant cells. It was so cool! 

TEST DAY

I honestly have no idea what to post on test days. I'm pretty sure I post the same thing on every test day: I have no idea how I did on the test. I studied, I knew my stuff, but I still don't really know how I did on the actual test. You see, tests/quizzes and I don't really work well together. They do this thing to me where they make me second guess myself. For some weird reason, I know and have the right answer, but I end up putting a different answer. I feel like I did that a lot on this last test. Well, I guess I won't really know until I get my test back.

Pedigree

The picture above is an example of a pedigree. A pedigree is kind of like a family tree but for genetics. Pedigrees contain genetic information that can help track and predict certain traits or diseases. There are many symbols that mean certain things. For example, a square that is not filled in is the symbol for a male, and a triangle that is not filled in is the symbol for a female. You can see what the other symbols are and what they mean in the image above.

In a pedigree, one must determine the condition and mode of inheritance...

Condition: sex-linked or autosomal

Mode of inheritance: recessive or dominant

Sex-linked means that the mother is the carrier of a disease and there is a possibility that she will pass it onto her children 

Autosomal refers to any of the chromosomes other than the sex-determining chromosomes (ex: X 
and Y)...in other words, not sex-linked