Make-up Mitosis Test due Sunday before 10:00
February 25, 2010
Please submit your answers before 10:00 on Sunday night. Your two grades will be averaged. Do not cut and copy answers from the internet–I will know!
1. Define Mitosis.
2. What is the resting phase of the cell cycle called? Explain why this stage is really not resting.
3. List the stages of Mitosis and explain in detail what occurs in each stage.
4. How many chromosomes are in human body cells? How many chromosomes are there in the beginning in Prophase? How many chromosomes will be in the two daughter cells once the cells divide?
5. Explain the process of cytokinesis.
6. What is the purpose of spindle fibers? Where are they attached to the chromosome?
7. What is the purpose of the centromere?
8. What is found on the chromosomes or chromatids?
9. What is the difference between a cleavage furrow and a cell plate?
10. What is the disease called when cells overly reproduce? What are some treatments for this disease?
Stems for March 2nd
February 23, 2010
Atmo—Atmosphere, atmometer, atmospheric
Stems for Feb. 23rd
February 20, 2010
cranio (skull) craniology, intracranial. craniotomy, cranium, dolichichranic
Contaminated House Dust Linked to Parking Lots With Coal Tar Sealant
February 17, 2010
Coal-tar-based sealcoat — the black, shiny substance sprayed or painted on many parking lots, driveways, and playgrounds — has been linked to elevated concentrations of the contaminants polycyclic aromatic hydrocarbons (PAHs) in house dust. Apartments with adjacent parking lots treated with the coal-tar based sealcoat contained house dust with much higher concentrations of PAHs than apartments next to other types of parking lots, according to new research published online in Environmental Science and Technology (ES&T).
The study was conducted in Austin, Texas, by scientists at the U.S. Geological Survey (USGS).
Coal tar is a byproduct of the coking of coal, and can contain 50 percent or more PAHs by weight. Coal-tar-based pavement sealants therefore have very high levels of PAHs compared to other PAH sources (e.g., soot, vehicle emissions, used motor oil). PAHs are an environmental health issue because several are probable human carcinogens and they are toxic to fish and other aquatic life.
Small particles of sealcoat, which contains extremely high concentrations of PAHs, likely are tracked indoors by residents after they walk across the parking lot. The study found that apartments adjacent to coal-tar-sealcoated parking lots contained concentrations of PAHs in house dust with that were 25 times higher than in house dust from apartments with concrete, asphalt, Read more
Chickens ‘One-Up’ Humans in Ability to See Color
February 17, 2010
Researchers at Washington University School of Medicine in St. Louis have peered deep into the eye of the chicken and found a masterpiece of biological design.
Scientists mapped five types of light receptors in the chicken’s eye. They discovered the receptors were laid out in interwoven mosaics that maximized the chicken’s ability to see many colors in any given part of the retina, the light-sensing structure at the back of the eye.
“Based on this analysis, birds have clearly one-upped us in several ways in terms of color vision,” says Joseph C. Corbo, M.D., Ph.D., senior author and assistant professor of pathology and immunology and of genetics. “Color receptor organization in the chicken retina greatly exceeds that seen in most other retinas and certainly that in most mammalian retinas.”
Corbo plans follow-up studies of how this organization is established. He says such insights could eventually help scientists seeking to use stem cells and other new techniques to treat the nearly 200 genetic disorders that can cause various forms of blindness.
Blogs ARMT Feb. 22, 23,24, 25,26, 2010
February 17, 2010
1. Which statement describes the process of growth within an organism?
a. A green vine uses energy from the Sun to produce more cells.
b. A fire produces more heat as additional fuel is added.
c. An oak tree drops its leaves when the seasons change.
d. An animal’s fur is raised when it senses danger.
.Notes – Genetics
February 16, 2010
Genetics: The Science of Heredity.
Genetics PDF Download
Lesson 1 A Priest-Scientist Gregory Mendel
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Mendel’s Three Genetic Laws
February 16, 2010
We spoke in class about Mendel’s Three Laws of Genetics —it is so imperative that each of you learn them. We will do more review in class—-
I. The Law of Dominance
If a cross of parents that are pure for contrasting traits, only one form of the trait will appear in the next generation. Offspring that are hybrid for a trait will have only the dominant trait in the phenotype.
My explanation: Cross PP x pp and all offspring with be Heterozygous Pp and all purple.
—–Any time two parent organisms look different for a trait, and all their offspring resemble only one of the parents, you are dealing with Mendel’s Law of Dominance
2. The law of Segregation—During the formation of gametes (eggs and sperms), the two alleles responsible for a trait separate from each other. Alleles for a trait are then”recombined” at fertilization, producing the genotype for the traits of the offspring.
My understanding: Mendel crossed plants from the F1 generation, Pp and Pp, 3/4 plants will be purple and 1/4 will be white. —-Therefore, the genes must segregate themselves between the production of sex cells and fertilization. —This must happen in the process of Meiosis, which is the production of sex cells, egg and sperm.
Any time two parents have the same phenotype for a trait (tall, short, purple, white, etc) but some of their offspring look different with the respect to that trait, the parents must be hybrid or heterozygous for a trait.
3. The Law of Independent Assortment—Alleles for different traits are distributed to sex cells and offspring independently of each other.
Mendel realized that height, shape, color, texture, or any of the peas plant traits had an impact on each other. So, being tall wouldn’t determine if the plants would be green or yellow. Therefore, different traits seemed to be inherited INDEPENDENTLY. Example: RrGg x RrGg, round green x round green will produce 9/16 round green, 3/16 round yellow, 3/16 wrinkled green, 1/16 wrinkled yellow
Blog Feb. 12th
February 11, 2010
What do you know about Genetics?
Blog Feb. 11th
February 11, 2010
We traveled to Reflectives today to plant flowers for the Care Center. We learned many wonderful scientific from Mrs. McClintock, name a few new things that you learned. What did you enjoy most about the experience?
