Cancer
Define cancer.
What differentiates normal cells from cancer cells in terms of regulation?
Disease of uncontrolled cell growth. Normal cells have programmed chemical signals for cell division and cell death; cancer cells do not communicate (nonstop division).
How do water molecules stick together?
How do water molecules stick to other polar things?
COHESION
ADHESION
Define electronegativity
Measure of an atom's ability to attract electrons (how strongly it pulls electrons towards it)
What is the difference between an element and a molecule?
Elements are pure substances made up of one type of atom (ex: oxygen, carbon, hydrogen)
Molecules are groups of two or more elements chemically bonded together (H2O, O2, CO2)
What percentage of Americans will be diagnosed with some form of cancer in their lifetime?
40%
When mixed, why does vegetable oil sit on top of water, but salt dissolves into water?
Oil is HYDROPHOBIC
Salt is HYDROPHILIC
Since water is polar, it can only dissolve other polar molecules.
How many electron pairs are shared in a single covalent bond?
1 pair, 2 electrons
State the 3 atomic particles. Are they located in the nucleus or the electron cloud? What are their charges and masses?
Proton: +, nucleus, 1 atu
Neutron: no charge, nucleus, 1 atu
Electron: -, electron cloud, no mass
Lung & bronchus cancer isn't the single most-diagnosed cancer in either men or women, but it's the leading cause of cancer death for both. What does that gap between how often it's diagnosed and how often it's fatal suggest about this cancer — either about a major modifiable risk factor behind it, or about how early it's typically caught.
Usually diagnosed at later stages due to a lack of symptoms in earlier stages. Usually caused by environmental factors (CARCINOGENS) like smoking.
Is water polar or nonpolar? Explain why or why not.
Do the elements that make up water contain no charges, partial charges, or full charges? What are the charges of each element?
Oxygen has a partial negative charge because it is pulling the electrons closer. Hydrogen has a partial positive charge because it is less electronegative and the electrons are being pulled away from it.
Two atoms form a bond where one atom pulls the shared electrons much closer to itself than the other. Name the bond type and predict whether the resulting molecule is more likely to dissolve in water or in oil.
Polar covalent (unequal sharing of electrons). More likely to dissolve in WATER (water is polar).
How many electrons fit in the inner ring? Outer rings? What is the outermost ring called?
2 in inner ring
8 in outer rings
Valence shell
I: Tumor grows from a single cancer cell (tissue)
II: Cancer spreads to neighboring tissues
III: Cancer enters the bloodstream
IV: Cancer spreads to another body part/organ.
What holds a SINGLE water molecule together?
What holds MULTIPLE water molecules together?
Polar covalent bond
Hydrogen Bond
What's happening to the electrons in each bond and what does it result in?
Hydrogen Bond
Polar Covalent Bond
Nonpolar Covalent Bond
Ionic Bond
Hydrogen Bond: No electron sharing or transferring; opposite partial charge attraction creates weak bonds
Polar Covalent Bond: Unequal sharing of electrons, partial charges
Nonpolar Covalent Bond: Equal sharing of electrons, no charges
Ionic Bond: Transfer of electrons, full charges
Calcium is element 20 (atomic number) on the periodic table. How many valence electrons does it have? How many protons and neutrons? What's the atomic mass?
2 valence electrons:
- 2 in inner shell, 8 in second shell, 8 in third shell, 2 in valence shell
20 protons, 20 neutrons
Mass is 40 amu (20p + 20n = 40)
A biopsy confirms cancer cells in two lymph nodes near a patient's primary tumor, but imaging shows no tumors anywhere else in the body. Using the staging framework, what stage is this cancer most likely at, and what evidence points you there?
Stage II: Cancer has invaded neighboring tissues.
What elements must be present for a molecule to be considered organic?
Carbon and Hydrogen
NaCl (sodium chloride, table salt) Na = 0.93, Cl = 3.16
- Ionic, polar covalent, nonpolar covalent?
- Will the atoms be uncharged, partially charged, or fully charged? If charged, which is + / - ?
- Hydrophobic or hydrophilic? Why?
Ionic, electronegativity difference above 1.8.
Fully charged: CATION Na+ (loses an electron), ANION Cl- (gains an electron)
Hydrophilic because of positive and negative charges.
Carbon-13 and Carbon-14 are common isotopes of Carbon. Carbon's atomic number on the periodic table is 6.
Identify what an isotope is.
How many p, n, and e are in each form?
What happens if we take away two protons from Carbon?
Isotopes are different forms of the same element due to differing numbers of neutrons.
Carbon 12: 6p, 6n, 6e
Carbon 13: 6p, 7n, 6e
Carbon 14: 6p, 8n, 6e
If we take away two protons, Carbon turns into a different element. Protons can NEVER change.