Microbial Genetics [5]

Question 1

What are Genes?

Answer 1

Units of hereditary material containing the info that determines characteristics of organism.

Segments of DNA specifying a particular protein chain.

Question 2

How many bases does the average gene have?

Answer 2

1000

Question 3

Define Genome.

Answer 3

The complete set of genes present in an organism.

Question 4

Genotype vs. Phenotype

Answer 4

Genotype: genetic makeup, precise genetic constitution of an organism

Phenotype: observable properties, what you look like

Question 5

Cells genome is organized into ___________ .

Answer 5

Cells genome is organized into chromosomes.

Question 6

What is a chromosome?

Answer 6

A genetic element carrying genes that contains hereditary information.

Question 7

Prokaryotes vs. Eukaryotes genetic material?

Answer 7

Prokaryotes: single chromosome, circular DNA molecule

Eukaryotes: several chromosomes, linear DNA molecule

Question 8

DNA

Answer 8

Deoxyribonucleic Acid, contains the genetic code for most living things

Question 9

What is the genetic code?

Answer 9

information for the synthesis of proteins is contained in the nucleotide sequence of a DNA molecule

Question 10

What is binary fission?

Answer 10

The division of one cell into two cells by the formation of a septum. (Bacteria reproduce by binary fission.)

Question 11

What is DNA? What is DNA composed of?

Answer 11

double stranded, helical molecule composed of building blocks called deoxyribonucleotides

three parts;

1- deoxyribose sugar; 5-carbon sugar

2- nitrogenous base; Adenine, Thymine, Cytosine, Guanine

3- Phosphate group

Question 12

Identify DNA Complementary Base Pairs

Answer 12

A-T

G-C

Question 13

What’s attached to the 5’ end?

What’s attached to the 3’ end?

Answer 13

5’ end - phosphate group

3’ end - hydroxyl group (OH)

Question 14

Why are two strands of DNA antiparallel (oriented in opposite directions)?

Answer 14

in order for paired bases to be next to each other

Question 15

What is DNA replication?

Answer 15

Conversion of one double stranded DNA molecule into two identical double stranded molecules.

Each parent acts as a template for synthesis of another strand by complementary base pairing.

Question 16

How does DNA polymerase work?

Answer 16

5’ to 3’, only adds nucleotides to 3’ end.

Question 17

During replication the DNA polymerase can only join?

Answer 17

the phosphate group of a 5’ carbon of a new nucleotide to the hydroxyl group of the 3’ carbon of a nucleotide already in the chain

Question 18

Phosphodiester Bond

Answer 18

the bond that joins the nucleotides

Question 19

What is the leading strand?

Answer 19

portion of DNA replication where synthesized continuously

Question 20

What is the lagging strand?

Answer 20

synthesized (discontinuously) in pieces called Okazaki fragments

Question 21

How is DNA replication semiconservative?

Answer 21

each strand in the DNA double helix acts as a template for the synthesis of a new, complementary strand

Question 22

What are the differences of Eukaryotic and Prokaryotic replication?

Answer 22

Eukaryotes contain multiple origins of replication, Prokaryotes contain a single origin of replication.

Eukaryotes nucleus must undergo mitosis (division of daughter cells) after replication.

Question 23

Cells use info in RNA

Answer 23

Cells use info in RNA to synthesize proteins.

Question 24

Genetic info in DNA is copied or transcribed into

Answer 24

Genetic info in DNA is copied or transcribed into a complementary base sequence of RNA.

Question 25

Name the three types of RNA

Answer 25

1. Messenger RNA (mRNA) 2. Ribosomal RNA (rRNA) 3. Transfer RNA (tRNA)

Question 26

What is Messenger RNA (mRNA)?

Answer 26

Messenger RNA (mRNA) carries the coded information for making specific proteins.

Question 27

What is Ribosomal RNA (rRNA)?

Answer 27

Ribosomal RNA (rRNA) forms integral part of ribosome for protein synthesis.

Question 28

What is Transfer RNA (tRNA)?

Answer 28

Involved in protein synthesis.

Question 29

What is transcription?

Answer 29

strand of mRNA is synthesized using a portion of cell's DNA as template; genetic info in bases of DNA are rewritten in base sequence of mRNA Base pairing of DNA with RNA Adenine pairs with Uracil

Question 30

DNA polymerase can only add nucleoside triphosphate to?

Answer 30

DNA polymerase can only add nucleoside triphosphate to free OH group (3 prime end).

Question 31

Where does transcription and translation occur in Prokaryotes and Eukaryotes?

Answer 31

In Eukaryotes, transcription occurs in the Nucleus, translation occurs in Cytoplasm. In Prokaryotes, transcription and translation are coupled.

Question 32

Describe Transcription.

Answer 32

RNA polymerase binds to DNA at Promoter One DNA strand is template for RNA synthesis, synthesized 5' to 3' by complementary base pairing

Question 33

5' end is

Answer 33

Phosphate end

Question 34

Each codon codes for ? .

Answer 34

Each codon codes for specific amino acid.

Question 35

What is translation?

Answer 35

Protein synthesis using mRNA as a template.

Question 36

In mRNA sequence, each group of 3 nucleotides is called?

Answer 36

Codon

Question 37

DNA polymerase can only add where?

Answer 37

3' prime OH group