Biology Test # 1 , Study Guide Test

How many electrons does carbon have in its valence shell? A. 4 B. 5 C. 7 D. 8 E. 14

A, 4

Fluorine has an atomic number of 9 and a mass number of 19. How many electrons are needed to complete the valence shell of fluorine atom? A. 1 B. 3 C. 0 D. 7 E. 9

A. 1

In DNA what always base pairs with cytosine? A. Guanine B. Adenine C. Cytosine D. Thymine

A. Guanine

The partial negative charge in a molecule of water occurs because A. The oxygen atom acquires an additional electron B. the electrons shared between the oxygen and hydrogen atoms spend more time around the oxygen atom's nucleus than around the hydrogen atom's nucleus. C. the oxygen atom has two pairs of electrons in its valence shell that are not neutralized by hydrogen atoms D. the oxygen atom forms hybrid orbitals that distribute electrons unequally around the oxygen nucleus. E. one of the hydrogen atoms donates an electron to the oxygen atom.

B. the electrons shared between the oxygen and hydrogen atoms spend more time around the oxygen atom's nucleus than around the hydrogen atom's nucleus.

If an antibiotic kills 99.9% of bacterial population, you would expect the next generation of bacteria... A. to be just as susceptible to that antibiotic as was the previous generation. B. to be more resistant to that antibiotic C. to die out due to the drastic decrease in population D. to be more contagious than the prior generation

B. to be more resistant to that antibiotic

Which of the following are qualities of any good scientific hypothesis? I. It is testable II. It is falsifiable III. It produces quantitative date IV. It produces results that can be replicated 1. I only 2. II only 3. I and II 4. III and IV

D. I and II

Which bond or interaction would be difficult to disrupt when compounds are put into water? A. covalent bonds B. hydrogen bonds C. van der Waals interaction D. ionic bonds E. either covalent bonds or ionic bonds

A. covalent bonds

An ionic chemical bond is one in which? A. electrons are removed from one atom and transferred to another atom so that the two atoms become oppositely charged and are attracted to each other. B. Protons and neutrons are shared by two atoms so as to satisfy the requirements of both atoms. C. outer-shell electrons of two atoms are shared so as to satisfactorily fill the outer electron shells of both atoms.

A. electrons are removed from one atom and transferred to another atom so that the two atoms become oppositely charged and are attracted to each other.

Which of the following correctly describes chemical equilibrium? A. forward and reverse reactions continue with no effect on the concentrations of the reactants and products. B. The concentrations of the products are higher than the concentrations of the reactants. C. Forward and reverse reactions have stopped so that the concentration of the reactants equals the concentration of the products. D. Reactions stop only when all reactants have been converted to products. E. There are equal concentrations of reactants and products, and the reactions have stopped.

A. forward and reverse reactions continue with no effect on the concentrations of the reactants and products.

An atom has a total of 6 electrons in its outer shell. How many unpaired electrons does it have? A. 0 B. 2 C. 4 D. 6

B. 2

A water sample from a hot thermal vent contained a single-celled organism that had a cell wall but lacked a nucleus. What is its most likely classification? A. Eukarya B. Archaea C. Animalia D. Protista E. Fungi

B. Archaea

The nucleus of a nitrogen atom contains 7 neutrons and 7 protons. Which of the following is a correct statement concerning nitrogen? A. The nitrogen atom has a mass number of approximately 7 an an atomic number of 14. B. The nitrogen atom has a mass number of approximately 14 and an atomic number of 7. C. The nitrogen atom has a mass number of approximately 14 an an atomic number of 14. D. The nitrogen atom has a mass number of approximately 7 and an atomic number of 21. E. The nitrogen atom has a mass number of approximately 14 and an atomic number of 21.

B. The nitrogen atom has a mass number of approximately 14 and an atomic number of 7.

The atomic number of nitrogen is 7. Nitrogen -15 is heavier than nitrogen -14 because the atomic nucleus of nitrogen -15 contains how many neutrons? A. 6 B. 7 C. 8 D. 12 E. 14

C. 8

Which of the following statements about genetics is true? A. Genes are proteins that produce DNA. B. DNA is made up of six different kinds of nucleotides. C. Differences among organisms reflect different nucleotide sequences in their DNA. D. Each DNA molecule is a single strand of nucleotides.

C. Differences among organisms reflect different nucleotide sequences in their DNA.

A cell that lacks organelles is a(n) A. member of the Kingdom Plantae B. animal cell C. prokaryotic cell D. eukaryotic cell

C. Prokaryotic cell

Carbon -12 is the most common isotope of carbon and has a mass number of 12. However, the atomic mass of carbon as shown on the periodic table is slightly more than 12 daltons. WHy? A. The atomic mass does not include the mass of electrons B. Some carbon atoms in nature have an extra proton. C. Some carbon atoms in nature have more neutrons. D. Some carbon atoms in nature have a different valence electron distribution. E. Some carbon atoms in nature have undergone radioactive decay.

C. Some carbon atoms in nature have more neutrons.

In comparison to eukaryotes, prokaryotes_____. A. are more structurally complex B. are larger C. are smaller D. do not have membranes

C. are smaller

One liter of a solution of pH2 has how many more hydrogen ions (H+) than 1 L of a solution of pH6? A. 3 times more B. 16 times more C. 40,000 times more D. 10,000 times more E. 100,000 times more

D. 10,000 times more

In what way are elements in the same column of the periodic table the same? A. They have the same number of protons B. They have the same number of neutrons C. They have the same number of electrons D. They have the same number of electrons in their valence shell. E. They have the same number of electron shells.

D. They have the same number of electrons in their valence shell.

Which is the correct sequence of increasing organization? A. Molecule, cell, organelle, organ B. Organelle, tissue, cell, organ C. Atom, Molecule, tissue, cell D. Organ, tissue, cell, molecule E. Cell, tissue, organ, organ system

E. Cell, tissue, organ, organ system

A solution contains 0.0000001 moles of hydroxyl ions (OH-) per liter. Which of the following best describes the solution? A. acidic: H+ acceptor B. basic: H+ acceptor C. acidic: H+ donor D. basic: H+ donor E. neutral

E. neutral