BIOA01H3 Chapter 2: Chapter 2 (Fall2010)

Which of the following is true?

Thanks.

1. An ionic bond between two atoms is formed as a result of the ______________.

a) sharing of electrons

b)transfer of electrons from one atom to the other.

c) loss of electrons from both atoms.

d) loss of a proton from one atom

2. Choose the phrase that best completes this sentence: Microtubules ____________ and are required to pull duplicated chromosomes to opposite poles of dividing cells.

a)generate contractile forces

b)are intermediate in thickness

c)are found in especially large numbers in muscle cells

d)can rapidly reorganize

3. Which subatomic particles contribute to the atomic number for any given element?

a)protons

b)neutrons

c)protons and electrons

d)protons and neutrons

ATOMIC STRUCTURE

1. A neutral oxygen atom (atomic number = 8) has 8 electronslocated in 2 different electron orbitals. TrueFalse

2. Hydrogen has only one neutron and no protons in itsnucleus. TrueFalse
3. An atom consists of a central nucleus surrounded by electronsthat are in constant motion. TrueFalse
4. Almost all of the mass of an atom is concentrated in itselectrons. TrueFalse
5. The orbital of an electron is the volume of space where theelectron is most likely to be found. TrueFalse
6. Almost all of the volume of an atom is emptyspace. TrueFalse
7. The reactivity or chemical behavior of an atom depends primarilyon the number of neutrons it has. TrueFalse
8. Modern physics indicates that we cannot determine the exactlocation of a particular electron at any giventime. TrueFalse
9. Electrons are maintained in their orbitals by their attractionto the positively charged nucleus. TrueFalse
10. Atomic orbitals represent probability distributions forelectrons and come in a variety of shapes. TrueFalse