UNIT 1

Question 1

What are the 5 points of cell theory?

Answer 1

• all organisms are made of cells
• the cell is the fundamental unit of life
• cells come from preexisting cells
• there is no life without cells
• the cell is the smallest unit of life

Question 2

What are the three domains on the tree of life?

Answer 2

eukaria, bacteria, archaea

Question 3

Why can the results from studies of cellular processes in the bacterium E. coli be applied to cellular processes that occur in humans?

Answer 3

It shares a common ancestor with eukaryotes so many processes are conserved.

Question 4

Which cellular structures or compartments are found in all cells?

Answer 4

ribosomes, cytosol, plasma membrane

Question 5

What differentiates eukaryotes from prokaryotes?

Answer 5

• prokaryotes do not have membrane bound compartments
• eukaryotes have a nucleus surrounded by a nuclear envelope, many membrane bound compartments such as mitochondria and chloroplasts

Question 6

A human immunodeficiency virus (HIV) consists of a shell of proteins surrounding a single strand of RNA, all surrounded by a lipid bilayer.

List the macromolecules found in the virus.

Answer 6

RNA, proteins, lipids

Question 7

Describe at least two reasons that a virus does not meet the criteria to be considered a cell.

Answer 7

• it cannot replicate on its own without a host cell

- no metabolism

Question 8

How does a cell use carbon?

Answer 8

amino acids, lipids, carbohydrates, nucleic acid building blocks

Question 9

How does a cell use nitrogen?

Answer 9

forming side chains of amino acids, forming nitrogenous bases,

Question 10

How does a cell use oxygen?

Answer 10

building blocks for all macromolecules

Question 11

How does a cell use phosphorous?

Answer 11

phosphate group attached to lipids, nucleotide building block

Question 12

Which phase(s) is the overall pop. not actively dividing?

Answer 12

Lag phase

Question 13

Which phase(s) is the overall pop. number not increasing?

Answer 13

lag phase, stationary phase, death phase

Question 14

Which phase(s) is the overall pop. dividing exponentially?

Answer 14

exponential phase

Question 15

Which phase(s) is the death rate higher than the growth rate?

Answer 15

death phase

Question 16

Which phase(s) are the essential nutrients becoming limited?

Answer 16

stationary phase, and death phase

Question 17

Which phase(s) is DNA being replicated prior to cell division?

Answer 17

lag, exponential, stationary, death

Question 18

In which phase(s) is transcription and translation occurring within the cell?

Answer 18

lag, exponential, stationary, death

Question 19

which phase is binary fission occurring in cells?

Answer 19

exponential, stationary, death

Question 20

What would happen if lactose was removed from the media mid-way through A?

Answer 20

the cells would not enter the exponential phase and would stay in lag phase

Question 21

What would happen if lactose was removed from the media mid-way through B?

Answer 21

the cells would enter stationary phase sooner and the maximum number of cells would be lower

Question 22

What would happen if lactose was removed from the media mid-way through C?

Answer 22

the cells may enter the death phase sooner, and the death rate of cells would remain the same

Question 23

What would happen if lactose was removed from the media mid-way through D?

Answer 23

nothing

Question 24

An example of a noncovalent bond or interaction that is common within and between macromolecules is a

Answer 24

hydrogen bond

Question 25

Two large proteins are interacting and held together by non-covalent bonds (interactions) on their surfaces. Why can these non-covalent bonds hold the proteins together?

Answer 25

There are many bonds

Question 26

In macromolecular synthesis/polymerization, what type of bond would join two amino acid subunits?

Answer 26

peptide bond

Question 27

In macromolecular synthesis/polymerization, what type of bond would join two monosaccharide subunits?

Answer 27

glycosidic

Question 28

In macromolecular synthesis/polymerization, what type of bond would join two nucleotide subunits?

Answer 28

phosphodiester bond

Question 29

In lipid synthesis/polymerization, what type of bond would join two fatty acid tails to a glycerol backbone?

Answer 29

ester bond

Question 30

A hydrogen bond is a special case of which non-covalent interaction?

Answer 30

PD-PD

Question 31

When two atoms are involved in a polar covalent bond, what is the charge on each atom?

Answer 31

One has a permanent partial positive (delta+) and the other a permanent partial negative (delta-).

Question 32

When two atoms are involved in a nonpolar covalent bond, what is the charge on each atom?

Answer 32

Both atoms fluctuate between partial positive and partial negative charges.

Question 33

When an atom is part of a polar covalent bond, what types of noncovalent interactions are possible for this atom to be part of, with another atom?

Answer 33

ion-PD, PD-PD, PD-ID

Question 34

When an atom is part of a nonpolar covalent bond, what is the strongest noncovalent interaction that it is possible for this atom to be part of, with another atom?

Answer 34

PD-ID

Question 35

When an atom or functional group is ionized (e.g. an NH3+ group or a COO- group) what is the strongest type of noncovalent interaction(s) is possible for it to be part of, with another atom/group?

Answer 35

ionic

Question 36

A membrane protein made up of a single polypeptide forms an alpha helix as it crosses the lipid bilayer. What can you say about this protein? - The R-groups found within the transmembrane domain are non-polar. - The R-group interactions are the primary factor stabilizing its secondary structure. - Hydrogen bonds among backbone carbonyl and amide groups can be found in the transmembrane domain. - The quaternary structure is determined by its interactions with fatty acid tails.

Answer 36

- Hydrogen bonds among backbone carbonyl and amide groups can be found in the transmembrane domain. - the R-groups found within the transmembrane domain are non-polar

Question 37

A RNA-binding protein binds to the nucleic acid backbone using the amino acyl residue histidine. What do you predict would happen to RNA binding activity if histidine was replaced with isoleucine?

Answer 37

Decreased binding of the protein to RNA

Question 38

What is the correct order that a monomer of RNA are connected?

Answer 38

phosphate-sugar-base

Question 39

Which region is required for a membrane carrier to move a solute against its concentration gradient, but is not required for a channel?

Answer 39

Active site for ATP binding

Question 40

What is true for BOTH the lag and stationary phase? - Cells synthesize macromolecules for those conditions. - Most cells are dividing. - Cells are active in binary fission with a similar number undergoing cell death. - The cells are encountering new growth conditions.

Answer 40

- Cells synthesize macromolecules for those conditions | - cells are encountering new growth conditions

Question 41

Which of the following statements are TRUE for the formation of lipid micelles in water? [Choose all that apply] - The phospholipids that form micelles can have one, two, or three fatty acid tails. - The entropy of the phospholipids increases during micelle formation. - The entropy of the water molecules increases when non polar lipid tails group together. - Lipids form micelles because the phospholipids cannot interact with water. - The assembly is spontaneous with negative delta G.

Answer 41

True: - the entropy of the water molecules increases when non-polar lipid tails group together - the assembly is spontaneous with negative delta G