SAT blog Thursday January 22nd
January 19, 2009
Neil wanted to see how the pressure in his bicycle tires changed with temperature. What is the dependent variable in this experiment?
a. the bicycle tires
b. the temperature
c. the air pressure in the tires
d. the height of the bicycle
SAT blog Wednesday January 21
January 19, 2009
1. Which of the following questions could a scientist try to answer through experimentation?
a. Do fish like to swim in fish tanks?
b. Were dinosaurs afraid of people?
c. Does more sunlight cause a flower to grow larger?
d. is it easier to play a guitar or a trumpet?
SAT Blog Tuesday January 20
January 19, 2009
If you want credit for the blogs, be sure that your answers are correct. Look the answer up on line or use your textbook.
1. Ella has brown hair and green eyes. What is the name of the segment of DNA that helps determines traits, such as brown hair and green eyes?
a. a chromosome
b. a nucleuc acid
c. a gene
d. a ribosome
SAT Blog Monday January 19th
January 19, 2009
1. Which small component of the respiratory system are responsible for the movement of oxygen through the blood?
a. bronchi
b.alveoli
c. nephrons
d. arteries
Jan. 16th SAT Questions
January 15, 2009
1. Which cells in the body fight disease?
a. red blood cells
b. white blood cells
c. liver cells
d. bone cells
Olive Skins Provide Natural Defense Against Colon Cancer, Study Suggests
January 14, 2009
Researchers from the University of Granada and the University of Barcelona have shown that treatment with maslinic acid, a triterpenoid compound isolated from olive-skin pomace, results in a significant inhibition of cell proliferation and causes apoptotic death in colon-cancer cells. Maslinic acid is a novel natural compound and it is able to induce apoptosis or programmed death in human HT29 colon-cancer cells via the intrinsic mitochondrial pathway.
New research suggest this could be a useful new therapeutic strategy for the treatment of colon carcinoma.
This study is the first to investigate the precise molecular mechanisms of the anti-tumoral and pro-apoptotic effects of maslinic acid against colon-cancer. Chemopreventive agents of a natural origin, often a part of our daily diet, may provide a cheap, effective way of controlling such diseases as cancer of the colon. A wide range of studies in recent years has shown that triterpenoids hinder carcinogenesis by intervening in pathways such as carcinogen activation, DNA repair, cell cycle arrest, cell differentiation and the induction of apoptosis in cancer cells.
Decline Of Plankton That Gobble Carbon Dioxide Coincided With Ancient Global Cooling
January 14, 2009
The evolutionary history of diatoms — abundant oceanic plankton that remove billions of tons of carbon dioxide from the air each year — needs to be rewritten, according to a new Cornell study. The findings suggest that after a sudden rise in species numbers, diatoms abruptly declined about 33 million years ago — trends that coincided with severe global cooling.
The study is published in the Jan. 8 issue of the journal Nature.
The research casts doubt on the long-held theory that diatoms’ success was tied to an influx of nutrients into the oceans from the rise of grasslands about 18 million years ago. New evidence from a study led by graduate student Dan Rabosky of Cornell’s Department of Ecology and Evolutionary Biology and the Cornell Laboratory of Ornithology takes into account a widespread problem in paleontology: that younger fossils are easier to find than older ones.
SAT Questions Jan. 14th
January 13, 2009
1. All of the following are functions of the nervous system except_______________
a. receiving information
b. responding to stimuli
c. maintaining homeostasis
d. preventing disease
New NASA Balloon Successfully Flight-Tested Over Antarctica
January 13, 2009
NASA and the National Science Foundation have successfully launched and demonstrated a newly designed super pressure balloon prototype that may enable a new era of high-altitude scientific research. The super-pressure balloon ultimately will carry large scientific experiments to the brink of space for 100 days or more.
This seven-million-cubic-foot super-pressure balloon is the largest single-cell, super-pressure, fully-sealed balloon ever flown. When development ends, NASA will have a 22 million-cubic-foot balloon that can carry a one-ton instrument to an altitude of more than 110,000 feet, which is three to four times higher than passenger planes fly.
“This flight test is a very important step forward in building a new capability for scientific ballooning based on sound engineering and operational development,” said W. Vernon Jones, senior scientist for suborbital research at NASA Headquarters in Washington. “The team has further work to do to enable the super pressure balloon to lift a one-ton instrument to a float altitude of 110,000 feet, but the team has demonstrated they are on the right path.”
Hind Wings Help Butterflies Make Swift Turns To Evade Predators, Study Finds
January 13, 2009
New tires allow race cars to take tight turns at high speeds. Hind wings give moths and butterflies similar advantages: They are not necessary for basic flight but help these creatures take tight turns to evade predators.
“To escape a predator, you don’t have to be fast, you just have to be more erratic,” said Tom Eisner, a world authority on animal behavior, ecology and evolution and the Jacob Gould Schurman Professor Emeritus of Chemical Ecology at Cornell. Eisner is co-author of a study on butterfly wings recently published in the Proceedings of the National Academy of Sciences (105: 43).
