Genetics

This link is about genetics

https://docs.google.com/drawings/d/1RLK4LBfoO1Acf19Em-hluluSGGhTV8d5cGPu3M8HZYc/edit

Stem cells

Cell-based therapies: Treatment in which stem cells are induced to differentiate into the specific cell type required to repair damaged or destroyed cells or tissues.

Differentiation: The process whereby an unspecialized embryonic cell acquires the features of a specialized cell such as a heart, liver, or muscle cell. Differentiation is controlled by the interaction of a cell's genes with the physical and chemical conditions outside the cell, usually through signaling pathways involving proteins embedded in the cell surface.

Embryonic stem cell line: Embryonic stem cells, which have been cultured under in vitro conditions that allow proliferation without differentiation for months to years.

In Vitro: Latin for "in glass;" in a laboratory dish or test tube; an artificial environment.

Plasticity: the adaptability of an organism to changes in its environment or differences between its various habitats.

Pluripotent: The state of a single cell that is capable of differentiating into all tissues of an organism, but not alone capable of sustaining full organismal development.

Proliferation: Expansion of the number of cells by the continuous division of single cells into two identical daughter cells.

Therapeutic cloning: The process of using somatic cell nuclear transfer (SCNT) to produce cells that exactly match a patient. By combining a patient's somatic cell nucleus and an enucleated egg, a scientist may harvest embryonic stem cells from the resulting embryo that can be used to generate tissues that match a patient's body. This means the tissues created are unlikely to be rejected by the patient's immune system. See also Somatic cell nuclear transfer (SCNT).

1. What are the unique properties of all stem cells?  Explain in your own words what each property means.

The unique properties of all the stem cells is that it can divide and renew themselves over a long period of time.

Stem cells: Cells with a ability to divide and give rise to specialized cells

Proliferate: Expansion of cells by division making a identical sister cell

Long term self renewal: The ability of stem cells to replicate them cells into the same non specialized cells over a long period of time.

Embryonic stem cells: Embryo that is capable of dividing without waiting a long period of time.

Adult stem cells: any body cell other than gametes (egg or sperm)

Cell division: A method where a single cell will divide into two cells

Human embryonic stem cells: A type of pluripotent stem cell derived from the inner cell

Signals: Internal and external that controls the structure and function of the cell.

Genes: A functional unit of DNA that is found on chromosomes

Microenvironment: The nutrients and the growth of the cell

Epigenetic: can turn genes on and off

Cell-Based Therapies: A treatment to repair damaged cells

hematopoietic stem cell: A stem cell that rises white and red blood cells

2. What are the two main kinds of stem cells used by researchers?  What are the major differences between the two types in terms of their sources and usefulness to researchers?  Give examples of possible uses for each type of stem cell.

The two main kinds of stem cells used by researchers are the embryonic stem cells and the adult stem cells.

Embryonic stem cells: forms muscle cells, nerve cells, and many other cell types.

Adult stem cells: Can repair dying cells and regenerate damaged tissues

3. List some of the diseases that scientists think may be treated using stem cell research and suggest how stem cells might be used to treat each disease.

The diseases that scientists think may be treated by using stem cell research is  

spinal cord injury: Inject human adult bone marrow into the spine.

stroke: Inject adult stem cells into the heart wall

4. What are the necessary characteristics that laboratory-manipulated stem cells will need to have in order to be successfully used in cell-based therapies (what will stem cells need to be able to do)?

Stem cells must be able to regenerate the damaged cells or tissues and need to stay healthy.

Cited source: http://stemcells.nih.gov/info/Pages/Default.aspx

Onion root lab

1. What percent of cells were in interphase? 55%

2. What percent were in mitosis (total of every phase except interphase)? 44%

3. Which phase of mitosis (not interphase) takes the longest according to your data? Why do you think that is? 

Prophase would take the longest according to my data because it may take a while for the nucleus to condense and then it will take a while for the Microtubules to become attached to the kinetochores.

4. How can you recognize a cell in interphase? 

The middle of cell is a big black circle

5. How can you recognize a cell in metaphase? 

The spindle fibers are stretching out and attached to the chromosome which the chromosomes will start to form a line.

6. How might you figure out how long (in minutes and/or seconds) each phase of the cell cycle takes based on the data from these onion root cells? Explain your logic and show your calculations and results below. 

Interphase is the longest step in the cell cycle so it may take 20 minutes

Prophase and that would be the second longest step which takes 27.78% of the cell cycle and that may take 5 minutes

Metaphase should take 1 minute because there are few steps and its only 8.33%

Anaphase may take a 30 seconds because the spindle fibers would attach to the chromosomes and it is only 5.56% of the cell cycle.

Telophase is the quickest step so it should take a 10 seconds because the spindle fibers will grab the chromosomes and start to divide the cell and that its only 2.78% of the cell cycle.

7. Produce a pie chart in Create-a-Graph that shows the relative lengths of each stage of the cell cycle in these cells including interphase and each stage of mitosis.

Cell cycle

How do cells determine wether to divide or not to divide? 
The way it determines to divide is by a signal to divide or not to divide.

What are the mechanics of the cell cycle and how is it controlled?
It is controlled by the proteins in the cell.

How does cancer develop? 
it develops when a cell decides to divide on its own without a signal to divide.

What roll do proto-oncogenes and tumor suppresser play in controlling the cell cycle?
The roll proto-oncogenes play is that they stimulate cell division and the accelerator.

How do cancer treatments work and why they are not good for the body?
 cancer treatments use high doses of radiation targeted at the cancer cells. The reason they are not good for the body is because of the radiation.

Why does a multicellular organism need to control and coordinate cell division?  
It needs to control and coordinate cell division because some cells don't need to divide all the time.

What might be the consequences of uncontrolled cell division in a multicellular organism?
The consequences of uncontrolled cell division in a multicellular organism is that it can cause mutation and the cells won't divide.

What does it mean when we say that there are several “checkpoints” that occur during the cell cycle?
it means that cells have to go through a process to be able to divide.

Give an example of an external signal that regulates cell division and explain how it works.
Internal controls: Protein molecules vary concentrations during the cell cycle.

Compare and contrast the functions of proto-oncogenes and tumor suppressor genes.Give an example of each and explain why mutations in these genes can lead to cancer.
Proto-oncogenes: stimulates cell division, go sign for the cell cycle, mutated cells always on.  

Proto-oncogenes can lead to cancer because the mutated genes will still be active and will keep on dividing.

Tumor suppressor genes: Inhibits cell division, the brake peddle of the cell cycle, keeps mutated cells off.

Tumor suppressor genes can lead to cancer because if it does not work properly it can cause it to grow out of control.

Microscope lab

In this lab I learned how to use a microscope and then do a test on it so me and my friends chose our own cell and we would focus on it after that we took a test.

Some cool pictures 

On the left is moss. In the middle is asparagus. On the right is a frog egg.

PKU (Phenylketonuria)

1. What enzyme is most commonly defective in people with phenylketonuria?

The enzyme that is the most commonly defective in people with phenylketonuria is enzyme Phenylalanine Hydroxylase.

2. What reaction does this enzyme catalyze? (What is the substrate and what product is produced?)

It causes mental retardation because it changes cells inside the brain.

3. Describe the symptoms of phenylketonuria.

lighter hair and skin a smaller than normal head and the skin has a musty odor.

4. What causes the symptoms of PKU, the lack of a substance or the buildup of one? Explain. 

The causes of the symptoms is that it causes the enzyme to not work properly by mutating the gene.

5. How common is phenylketonuria? How is it treated? 

1 in 10,000 births in caucasians and east asians, 1 in 2,600 in turks, 1 in 4,500 in irish, 1 in 143,000 in japanese, and it is exceedingly rare in africans.

The way PKU is treated is by having a low protein diet as soon as the disorder is diagnosed and stay on that diet as long as possible.

Cited Sources: http://www.ygyh.org
http://www.nspku.org

Pick Your Poison: Ricin

1.) Where is this substance found or produced? It is found in a castor bean 

2.) What kind of substance is it? Powder

3.) What are the specific molecules that it acts upon? It acts upon the cytosol and can inactivate over 1,500 ribosomes per minute and kill the cell.

4.) What are the symptoms of exposure to this substance? 

By ingestion causes vomiting, diarrhea, dehydration, low blood pressure, seizures, and liver. 

By inhalation causes difficulty breathing, fever, cough, nausea, heavy sweating, fluid in lungs and low blood pressure.

5.) How is exposure to this substance treated? If ricin gets on you get rid of your clothes and wash yourself by using large amount of soap and water. Then put away your clothes in a bag using a tong or any other tool then seal it into another bag and the local or state health department will take care if the rest.

Cited sources:  http://www.medicinenet.com/ricin/article.htm
http://poisonousplants.ansci.cornell.edu/toxicagents/ricin.html