ESA Science Department

Elizabeth Seton Academy Science Deparment Blog for all your Science needs! You may go to the blog specific to your class by clicking on the appropriate link. Check back often for useful links, study guides and listing of daily assignments.

Saturday, October 29, 2005

Happy Halloween!! (For Monday)

Physical Science:
We will be beginning Chapter 3, States of Matter, on Monday. As a matter of fact, we'll learn about how on Earth, matter is readily observed in three states: gas, solid and liquid. The kinetic theory is used to explain the behavior of these states of matter, including what occurs within a sample of a substance as the substance changes from one state to another. The forces of attraction that hold solids and liquids together are also a key factor.

Biology:
Important things to review before your test on Chapter 2 for Wednesday:

Why are atoms considered neutral?
What is atomic number? What is atomic mass?
Covalent, ionic bonds. The difference between atoms and ions.

What is polarity? Why is water polar? Another helpful link here to help you visualize this. Why do hydrogen bonds depend on polarity?
Be familiar with the terms solute and solvent when talking about the components of a salt solution.
Know the concept of chemical reactions, reactants, products, and what type of chemical reaction will usually occur spontaneously.

Understand the concept of polymerization; know the names of the monomers for each of the 4 major groups of organic molecules (carbohydrates, nucleic acids, proteins, lipids).
Name two essential roles that enzymes play in cells.

Understand the pH scale, acids, bases. Understand why a pH of 4.5 for a solution means that there are 1000 times more Hydrogen ions, [H+], than a solution with a pH of 7.5

Chemistry:
Important things to know for your test on Chapter 2 on Tuesday:

Understand extensive and intensive properties.
A (pure) substance is either an element or a compound, having a uniform and definite composition. Compounds are made up of elements, which are always present in the same proportion.
Compounds can be broken down into simpler substances (elements) by chemical means.
Mixtures can be identified as homogeneous (also known as a solution) and heterogeneous.

Mixture of subtances (with variable composition) can be broken down into simple substances (with definite composition) physically.
Understand the differences and importance of distillation and filtration.
A physical blend of two or more substances is a mixture (it has a composition that varies).
What is a phase?

Know the difference between physical changes and chemical changes.
Understand chemical equations, chemical reactions, reactants, products and the law of conservation of mass.
Know the three main clues that indicate a chemical reaction has taken place.
Know why there are exceptions to when color change and production of a gas do not always indicate chemical changes have taken place.
What is a precipitate?
But, here is a little more on the topic of elements and the sure-to-be "Book for November" in Oprah's Book of the Month Club.




Anatomy & Physiology:
Why are atoms considered neutral?
What is atomic number? What is atomic mass?

Covalent, ionic bonds. The difference between atoms and ions.
What is polarity? Why is water polar? Another helpful link here to help you visualize this. Why do hydrogen bonds depend on polarity?

Understand the concept of polymerization; know the names of the monomers for each of the 4 major groups of organic molecules (carbohydrates, nucleic acids, proteins, lipids).
Look at how enzymes work.

Understand the pH scale, acids, bases.
It will help you if you understand why a pH of 4.5 for a solution means that there are 1000 times more Hydrogen ions, [H+], than a solution with a pH of 7.5


Be prepared to answer the following questions for you Test on Chapter 2 on Wednesday:
1. It is determined that a patient is in acidosis. What does this mean, and would you treat the condition with a chemical that would raise or lower the pH?

2. A new-born is diagnosed with sickle-cell anemia, a genetic disease in which substitution of one amino acid results in abnormal hemoglobin. Explain to the parents how the substitution can have such a drastic effect on the structure of the protein.
To answer this, it may be helpful to understand more about sickle-cell anemia and hemoglobin.
This website talks about the mutation in the gene for the changed amino-acid Valine that leads to the clumping up of the protein:


Although several hundred HBB [hemoglobin] gene variants are known, sickle
cell anemia is most commonly caused by the hemoglobin variant [Sickle-cell
mutation gene]. In this variant, the hydrophobic amino acid valine takes the place of hydrophilic
glutamic acid at the sixth amino acid position of the HBB [hemoglobin] polypeptide chain.
This substitution creates a hydrophobic spot on the outside of the protein
structure that sticks to the hydrophobic region of an adjacent hemoglobin
molecule's beta chain. This clumping together (polymerization) of Hb S [Sickle-cell] molecules
into rigid fibers causes the "sickling" of red blood cells.



3. Johnny's body temperature is spiking upward. When it reaches 104 degrees F, his mother puts in a call to the pediatrician. She is advised to give Johnny children's aspirin and sponge his body with cool water to prevent a further rise in temperature. How might a fever (excessively high body temperature) be detrimental to Johnny's welfare?
To answer this you will need to know how temperature affects enzymes and enzyme denaturation.

0 Comments:

Post a Comment

<< Home