Exam 2

Question 1

Anabolism -

Answer 1

Sum of all biosynthetic reactions in a cell

Question 2

What is an example of a micronutrient?

Answer 2

Iron

Question 3

Which of the following statements is false?

Answer 3

Most available nitrogen is in organic forms

Question 4

Aseptic technique -

Answer 4

A series of practices to avoid contamination

Question 5

Activation energy is the energy:

Answer 5

Required to transform all reactants into their reactive state

Question 6

To ensure growth of a newly discovered bacterium with unknown nutritional requirements, it would be best to begin with a ___ medium rather than a ___ medium.

Answer 6

Complex / minimal

Question 7

A catalyst:

Answer 7

Changes the rate of the reaction but does not change the end amount of products

Question 8

The portion of an enzyme to which substrates bind is referred to as:

Answer 8

Active site

Question 9

In aerobic respiration, the final electron acceptor is ___.

Answer 9

Oxygen

Question 10

The functional unit of genetic information:

Answer 10

Gene

Question 11

Which statement is true concerning mRNA?

Answer 11

mRNA has a very short half-life

Question 12

Fermentation has a relatively low ATP yield compared to aerobic respiration because:

Answer 12

Oxidative phosphorylation yields a lot of ATP

Question 13

If an oxidation reaction occurs:

Answer 13

Simultaneous reduction of a different compound will also occur, because electrons do not generally exist alone in solution

Question 14

What’s the difference between a coenzyme and a prosthetic group?

Answer 14

Coenzymes are weakly bound whereas prosthetic groups are strongly bound to their respective enzymes

Question 15

AT-rich DNA will denature/melt:

Answer 15

At a lower temperature than GC-rich DNA

Question 16

Supercoiling is important for DNA structure because:

Answer 16

It condenses the DNA so that it can fit inside the cell

Question 17

How are plasmids different than chromosomes?

Answer 17

Plasmids contain genes that are NOT essential for cellular growth and replication

Question 18

Genes that encoded for polymerases, gyrases, ribosomal proteins, and other proteins essential to replication, transcription, and translation are present on:

Answer 18

Chromosomes

Question 19

The precursor of each nucleotide in a strand of DNA is:

Answer 19

Deoxynucleoside 5’-triphosphate

Question 20

DNA replication always proceeds in only one direction because the ___ of the incoming nucleotide is attached to the free ___ of the growing DNA strand.

Answer 20

5’-phosphate / 3’-hydroxyl

Question 21

Okazaki fragments -

Answer 21

Formed on the lagging strand during DNA synthesis

Question 22

In the process of transcription, promoters are specific sequences of ___ that are recognized by ___ ___.

Answer 22

DNA / sigma factors

Question 23

The flow of biological information begins with:

Answer 23

DNA replication

Question 24

DNA participates in protein synthesis through:

Answer 24

An RNA intermediate

Question 25

In all cells, a gene encodes for:

Answer 25

A protein, tRNA, rRNA depending on the specific gene

Question 26

What is an example of one codon?

Answer 26

CAG

Question 27

In all cells, genes are composed of:

Answer 27

Nucleic acids

Question 28

Transfer RNA molecules:

Answer 28

Function to transfer the correct amino acids to the ribosome during translation

Question 29

The template for RNA polymerase is ___, and the new RNA chain is ___ and ___ to the template.

Answer 29

DNA / antiparallel and complementary

Question 30

Codon -

Answer 30

A triplet of bases on an mRNA molecules

Question 31

Each adenine-thymine base pair has ___ hydrogen bonds, while each guanine-cytosine base pair has ___ hydrogen bonds.

Answer 31

Two / three

Question 32

During DNA replication, Okazaki fragments are linked together by ___, an enzyme that creates phosphodiester bonds between nicked fragments of DNA.

Answer 32

DNA ligase

Question 33

The codon on the ___ matches with the anticodon on the ___ to direct the addition of the correct amino acid to the growing polypeptide chain.

Answer 33

mRNA / tRNA

Question 34

An operon is a useful genetic element because it:

Answer 34

Allows coordinated expression of multiple genes in prokaryotes

Question 35

Transposable elements are:

Answer 35

Segments of DNA that move from one site to another

Question 36

The two strands of DNA double helix are held together by:

Answer 36

Hydrogen bonds between nucleotide bases

Question 37

DNA replication is started with a(n) ___, which, in most cases, in vivo is a short stretch of ___.

Answer 37

Primer / RNA

Question 38

You are given an unknown bacterial sample and are told to do an isolation streak on a blood agar plate. You inoculate the plate for 24 hours at 37C, and notice that the plate now displays an olive green hue where the organism is growing. What happened to the plate?

Answer 38

Alpha-hemolysis, partial destruction of red blood cells

Question 39

The number of cells per milliliter in this culture flask is 3.3x10^4. After performing a serial dilution, how many colonies will theoretically grow on this plate?

Answer 39

33