NVCC Bio 101 2m Ebersole

What domain(s) of life have a nucleoid region?

• Bacteria
• Archaea
• Eukarya
• All of the above
• None of the Above

How many valence electrons does Sodium (Na) have?

• 2

• 8

• 1

• 11

Answer explanation

The term "valence electrons" refers exclusively to the electrons in the outermost shell or orbital. For example, Sodium has 11 electrons, if only 2 can be in the first orbital, and only 8 can be in the second orbital, that leaves one left to occupy the final orbital also known as the valence shell. All the electrons in the valence shell are known as valence electrons.

The closer this number is to 1 (Alkali metals) or 7 (Halogens), the more reactive it is. Meaning that an atom with 4 valence electrons like carbon or silicon will not be very reactive. If an atom has a full valence shell (Nobel gases) it will not react with anything.

The atomic number of an element, and thus it's identity, depends on the number of...?

• Protons

• Neutrons

• Electrons

Answer explanation

The identity of an atom is solely dependent on the number of protons it has. For example, carbon has 6 protons, if I add or take away any it will no longer be carbon. If I take 1 away it's boron, if I add 53 it's Praseodymium.

Oil is ______ because it is ________.

• Hydrophobic, polar

• Hydrophilic, polar

• Hydrophobic, non-polar

• Hydrophilic, non-polar

Answer explanation

Water is a polar molecule, meaning that one side of the molecule is more positively or negatively charged than the other side. Because lipids are non-polar they cannot bind to interact with water in anyway. It is this phenomenon that causes oil to separate and float on water.

Draw an ionic bond using Lewis dot structures.

Potential examples, Sodium Chloride, Lithium Bromide, Magenesium oxide,

Define an Ion.

Cell walls give a cell more ...

• Structural integrity

• Flexibility

• Porosity

• Mobility

Cations have a _ charge. Anions have a _ charge.

• • Positive (+) , Negative (-)

• • Negative (-) , Negative (-)

• • Positive (+) , Positive (+)

• • Negative (-) , Positive (+)

Answer explanation

Easy way to remember

Cats make people happy, positive

Antagonists make people mad, negative

What is the weakest type of bond

• Hydrogen bond (H-bond)

• Covalent bond

• Ionic bond

• Van der Waals forces

Answer explanation

While Van der Waals forces are weaker than H-bonds, they are actually not a type of bond, but just a force that keeps molecules close to each other. Think of a dance, couples are interacting with each other (that's a bond), but the occasional bump or whatever with another couple because everyone is in the same area (that's Van der Waals forces.)

Cillia and Flaggella are made of (a)   in a (9+2) stucture