Moroney LSU Biology 1201 Exam 1
A molecule that has all nonpolar covalent bonds would be... (Exam 1)
hydrophobic
An element has 8 protons, 9 neutrons, and 8 electrons. Its atomic number and atomic mass, respectively are_____. (Exam 1)
8 and 17
While at the store you buy some celery. The cells in the celery stalks are_____. (Exam 1)
alive
sulfhydryl group (Exam 1)
-S-H
The atomic weight of water is 18. In 100 grams of water, there are about _____? (Exam 1)
5.6 moles
An unequal sharing of electrons between atoms results in... (Exam 1)
A polar covalent bond
Erythrose, a 4 carbon sugar, has the following chemical formula (Exam 1)
C4H8O4
The molecular formula of glucose is C6H12O6. What would be the molecular formula of a polymer mad by linking ten glucose molecules together? (Exam 1)
C60H102O51
This component is found in eukaryotic cells______. (Exam 1)
Carbohydrate lipid protein nucleic acid
Which of the following is a false statement with respect to cellulose? (Exam 1)
Cellulose is a major food source for all animals because it is easily digested
What organelle is shown in the picture? (Exam 1)
Chloroplast
Which if the following structures directs newly made proteins to their correct location in the cell? (Exam 1)
Golgi Apparatus
In which structure below do all of the atoms have reasonable numbers of chemical bonds? (Exam 1)
H | N / \ H H
Which of the structures is an impossible covalently bonded molecular? (Exam 1)
H H | | H - C - C = O - H | H
A compound contains hydroxyl groups as its predominant functional group. Which of the following statements is true concerning this compound? (Exam 1)
It should dissolve in water
In pure water about how many of the water molecules are dissociated into H+ and OH-? (Exam 1)
Less than 1 in 1 million water molecules has dissociated
carboxylic acid (Exam 1)
O // -C \ O-
The cytoskeleton is composed of______. (Exam 1)
Protein
Which one of the following functional group is important in protein folding? (Exam 1)
R-NH2 R-SH R-COOH R-OH
What is the main substance that makes up the interior of a potato tuber? (Exam 1)
Starch
The H+ concentration in a cola is 1X10-4 M. What is the pH of the solution? (Exam 1)
4
One strand of DNA has the sequence 5'A-T-A-A-G-G-A-T-3' (Exam 1)
5' A-T-C-C-T-T-A-T-3'
Large nucleic acids are synthesized from nucleotide monomers by which process? (Exam 1)
the removal water (dehydration reactions)
Which of the following is NOT a protein function? (Exam 1)
-Catalysis of chemical reactions -Protein is part of hair and ligaments -Communication between cells (hormones) -Proteins are important in our sense of hearing of hearing and vision
Why is water cohesive? (Exam 1)
-One side of the molecule is slightly positive and the other side slightly negative -Water molecules participate in hydrogen bonds.
A cell has a diameter of 100 um. What is that length in millimeters? (Exam 1)
0.1mm
An atom having an atomic number of 10 and a mass of 22 would be expected to have_____ neutrons (Exam 1)
12
What is the OH- concentration of the cola in the preceding question? (Exam 1)
1X10-10M
What is the approximate atomic mass of an atom with 16 neutrons, 15 protons, and 15 electrons? (Exam 1)
31 daltons
The R group of side chain of the amino acid serine is -CH2-OH. The R group or side chain of the amino acid leucine is -CH2-CH-(CH3)2. Where would you expect to find these amino acids in a globular protein in aqueous solution? (Exam 1)
Leucine would be in the interior, and serine would be on the exterior of the globular protein
The overall three-dimensional shape of a single polypeptide is called the _____. (Exam 1)
Tertiary structure
Insulin, a protein secreted by some pancreas cells is made on_____. (Exam 1)
The rough endoplasmic reticulum
In an alpha helix, a hydrogen atom participates in a covalent bond with a nitrogen atom of one amino acid and also weakly interacts with an oxygen atom. What is this second weaker interaction called? (Exam 1)
a hydrogen bond
Which four elements make up approximately 96% of living matter? (Exam 1)
carbon, hydrogen, nitrogen, oxygen
If the pH of a solution is decreased from pH 7 to pH 5, it means that the... (Exam 1)
concentration of OH- is 100 times less than what it was at pH7
Different atomic forms of an element contain the same number of protons but a different number of neutrons. What are these different atomic forms called? (Exam 1)
isotopes
the scientific method usually begins with ____. (Exam 1)
making observations
Which organelle prevents small charged molecules like Na+ from rapidly entering the cell? (Exam 1)
plasma membrane