Theories & Laws
What is a scientific theory? How is it different from other theories?
supported by a large body of evidence
constantly being challenged, tested, and modified as new information is obtained
Universally accepted among scientists
How many molecules are in a mole?
6.023 x 1023
For Al - 13 (26.982). how many protons, neutrons, and electrons are present in a neutral atom?
p = 13
e= 13
n= 14
What type of bond is formed when two or more of the same atom bond together?
nonpolar covalent
This biomolecule is a source energy and also structure within organisms
lipids
What three components of the cell make up all life?
DNA, mRNA, tRNA
Ribosomes
Proteins made of 20 amino acids
Of the following:
number of molecules, mass in grams, density, molar mass, volume
Which do a mole of cookies and a mole of chips have in common?
number of molecules
N, O, Cl, C
O
What is the difference between a molecule and a compound?
molecule is a group or cluster of two or more atoms held together by chemical bonds.
compound is a substance or material which is formed by two or more different types of elements which are combined chemically in a fixed proportion.
All biomolecules except this one can form polymers.
Lipids
List at LEAST two pieces of evidence that support the endosymbiotic theory.
Chloroplasts and mitochondria have two membranes
chroloplasts and mitochondria have their own chromosomes
chloroplasts and mitochondria have ribosomes similar in structure to other prokaryotes
chloroplasts and mitochondria reproduce by binary fission, the same as prokaryotes
The molecular weight of galactose is 180 Daltons.
Determine the mass (in grams) of galactose if you have 3.7 L of 50 mM galactose solution.
33.3 g
What three factors affect electronegativity?
number of protons in the nucleus
number of electrons
distance of the outer electrons from the nucleus
Determine which type of bond makes up each of the following:
NH3
CH4
NH3 - polar covalent
CH4- non polar covalent
At which level of the protein structure can we identify alpha and beta structures.
secondary
All organisms are made up of cells
Chemical reactions necessary for life take place within the cells
all cells arise only from existing cells
cells contain hereditary information in DNA
What is the pH of a 4.3 x 10-4 M solution of KOH?
10.6
Why are weak chemical bonds essential to life (2)?
Strengthens the shape of the larger molecules
Helps molecules reversibly adhere to each other
Responsible for properties such as cohesion and adhesion , as well as the lower density of ice
hydrogen bond
This reaction helps form the glycosidic linkage between monomer of carbohydrates
dehydration synthesis
In order to be considered living, what four functions must the organisms must accomplish which functions?
Uptake and process nutrients/energy
excrete wastes
respond to environmental stimuli and maintain homeostasis,
growth & reproduction
What is the pH and pOH of a solution made by adding water to 15 grams of hydroiodic acid (127.9) until the volume of the solution is 2500 mL?
pH= 1.3
pOH= 12.7
What do elements of the same group have in common?
same number of valence electrons
Which of the following pairs of elements is most likely to form an ionic compound?
magnesium and fluorine
oxygen and chlorine
nitrogen and sulfur
sodium and aluminum
Magnesium and fluorine
This specific example of a biomolecule is the precursor for some hormones and in high quantities can cause danger to organs.
Cholesterol - Lipid