Saturday, January 5, 2008
Fri-Day 1
Bio- HW due Tuesday- text outline of section 35.2
we continued our journey through the human digestive system, focusing on the extensive surface area of the lining of the small intestine. The finger-like projections, villi, are evolutionary adaptations (provide for human survival) because they maximize the surface area of the small intestine, which maximizes the amount of nutrients absorbed. The proteins, carbs, lipids, and nucleic acids get totally broken down to their respective building block/simple molecules. Secretions of juices from the liver (bile) and the pancreas (various proteases and lipases) aid the small intestine in its complete digestion of nutrients.
Peristalsis of the smooth muscular lining of the small intestine pushes the undigested food and fiber to the colon.
We emphasized the main purpose of the colon: to reabsorb water that has been used in digesting food; mucous, saliva, etc. are mostly water, which must not be lost, otherwise dehydration would occur.
We then saw that the undigested food and fiber, as well as a lot of bacteria that live in the colon, are then stored in the rectum and then pushed out via the voluntary striated muscles of the anus.
Next week, we will discuss general nutrition and then the system that regulates your body: the endocrine system.
Chem 7: we finished our discussion of polar vs. nonpolar covalent bonds between nonmetal atoms of molecules. We learned that, when there is an electronegativity difference of 0.6 or greater between the two bonding atoms, electrons are not equally shared and the more electronegative atom develops a PARTIAL negative charge.
We then learned the SIX step process to properly draw the Lewis structure of a molecule. You MUST practice this method exactly as taught or else you will make costly errors for the rest of the course. Drawing Lewis structures properly is one of the most practical and important skills in chemistry.
We will get some more practice with this during the molecular models lab.
You should start your homework packet this weekend.
Chem 8/9: we focused on polar vs. nonpolar covalent bonds between nonmetal atoms of molecules. We learned that, when there is an electronegativity difference of 0.6 or greater between the two bonding atoms, electrons are not equally shared and the more electronegative atom develops a PARTIAL negative charge.
We then learned the SIX step process to properly draw the Lewis structure of a molecule. You MUST practice this method exactly as taught or else you will make costly errors for the rest of the course. Drawing Lewis structures properly is one of the most practical and important skills in chemistry.
We then applied this skill in the molecular models lab, which we will continue on Monday. As you saw, in order to deduce the 3-D structure of a molecule, you must first know how to draw its Lewis structure, which shows you where the electrons are shared about the central atom.
You should start your homework packet this weekend.
We will get some more practice with this during the molecular models lab.
we continued our journey through the human digestive system, focusing on the extensive surface area of the lining of the small intestine. The finger-like projections, villi, are evolutionary adaptations (provide for human survival) because they maximize the surface area of the small intestine, which maximizes the amount of nutrients absorbed. The proteins, carbs, lipids, and nucleic acids get totally broken down to their respective building block/simple molecules. Secretions of juices from the liver (bile) and the pancreas (various proteases and lipases) aid the small intestine in its complete digestion of nutrients.
Peristalsis of the smooth muscular lining of the small intestine pushes the undigested food and fiber to the colon.
We emphasized the main purpose of the colon: to reabsorb water that has been used in digesting food; mucous, saliva, etc. are mostly water, which must not be lost, otherwise dehydration would occur.
We then saw that the undigested food and fiber, as well as a lot of bacteria that live in the colon, are then stored in the rectum and then pushed out via the voluntary striated muscles of the anus.
Next week, we will discuss general nutrition and then the system that regulates your body: the endocrine system.
Chem 7: we finished our discussion of polar vs. nonpolar covalent bonds between nonmetal atoms of molecules. We learned that, when there is an electronegativity difference of 0.6 or greater between the two bonding atoms, electrons are not equally shared and the more electronegative atom develops a PARTIAL negative charge.
We then learned the SIX step process to properly draw the Lewis structure of a molecule. You MUST practice this method exactly as taught or else you will make costly errors for the rest of the course. Drawing Lewis structures properly is one of the most practical and important skills in chemistry.
We will get some more practice with this during the molecular models lab.
You should start your homework packet this weekend.
Chem 8/9: we focused on polar vs. nonpolar covalent bonds between nonmetal atoms of molecules. We learned that, when there is an electronegativity difference of 0.6 or greater between the two bonding atoms, electrons are not equally shared and the more electronegative atom develops a PARTIAL negative charge.
We then learned the SIX step process to properly draw the Lewis structure of a molecule. You MUST practice this method exactly as taught or else you will make costly errors for the rest of the course. Drawing Lewis structures properly is one of the most practical and important skills in chemistry.
We then applied this skill in the molecular models lab, which we will continue on Monday. As you saw, in order to deduce the 3-D structure of a molecule, you must first know how to draw its Lewis structure, which shows you where the electrons are shared about the central atom.
You should start your homework packet this weekend.
We will get some more practice with this during the molecular models lab.
# posted by C @ 5:31 PM 
