Regulation of Gene Expression

Question 1

It contains MEMBRANE-BOUND intracellular structures such as a nucleus, mitochondria, and for photosynthetic eukaryotes, chloroplasts.

Answer 1

Eukaryotes

Question 2

It is composed of ONE OR MORE LINEAR DNA chromosomes.

Answer 2

Eukaryotic Genome

Question 3

It helps the genome organization be more COMPLEX and PROTEINS help with COILING.

Answer 3

Histones

Question 4

Is GENE REGULATION more elaborate due to the?

Answer 4

Larger genome, cell differentiation

Question 5

It is made up of DNA wound twice around 8 histones (2 of each of 4 main types) with “LINKER” DNA between the beads.

Answer 5

1st Level: Nucleosomes or “Beads on a String”

Question 6

It is made up of a tightly wound coil of nucleosomes held in position by a FIRST HISTONE (H1).

Answer 6

2nd Level: 30nm Chromatin Fiber

Question 7

It is made up of loops held in place by scaffolding (NONHISTONE) proteins.

Answer 7

3rd Level: Looped Domains

Question 8

It is made up of HIGHLY CONDENSED, compact domains.

Answer 8

4th Level: Chromosomes are visible during mitosis

Question 9

The cells must continually turn genes on and off in response to INTERNAL & EXTERNAL SIGNALS.

Answer 9

Gene regulation

Question 10

Expression of specific genes is most COMMONLY REGULATED at the?

Answer 10

Transcription

Question 11

The proteins can BIND DNA and either inhibit or facilitate the BINDING OF RNA POLYMERASE.

Answer 11

Transcription Initiation Regulation

Question 12

It provides binding sites for regulatory proteins that AFFECT RNA POLYMERASE activity.

Answer 12

Enhancer sequence

Question 13

The cells can REGULATE GENE EXPRESSION even after a gene is transcribed to rapidly respond to environmental changes.

Answer 13

Post-Transcriptional Regulation

Question 14

POST-TRANSCRIPTIONAL REGULATION rapidly responds to environmental changes by?

Answer 14

• RNA processing: alternate splicing
• mRNA Degradation: rate
• Translation Initiation: can be blocked by regulatory proteins.
• Protein Processing & Degradation: regulation can occur during any of these final
  steps.

Question 15

It is known as the “JUMIPING GENE”

Answer 15

Transposons

Question 16

He discovered the “INDIAN CORN”

Answer 16

Barbara McClintock

Question 17

What are the 2 main parts of GENOME AND PROTEIN CAPSID?

Answer 17

Host range varies and narrow

Question 18

There is usually a LARGE NUMBER OF PROTEINS, but the number of different kinds of proteins is usually small.

Answer 18

Viral Structures

Question 19

Capsid is formed from a REPEATING single type of protein with the overall shape
of a rigid rod.

Answer 19

Helical Structures

Question 20

Capsid is formed from 252 IDENTICAL PROTEIN MOLECULES arranged in a polyhedron with 20 triangular facets and an icosahedron.

Answer 20

Icosahedral Viruses

Question 21

What is an example of ICOSAHEDRAL?

Answer 21

Adenoviruses - which cause
respiratory infections in animals.

Question 21

Capsid is surrounded by a membranous envelope derived from the MEMBRANES OF THE HOST (Such membranes prevent detection by the immune system).

Answer 21

Influenza Viruses

Question 22

The (Viruses that infect bacteria) COMPLEX CASPIDS. The first seven studied were
nicknamed T1 – T7. They have an elongated icosahedral head and an elaborate protein tail.

Answer 22

Bacteriophages

Question 23

It RAPID DESTRUCTION of host cell

Answer 23

Lytic

Question 24

Viral DNA INTEGRATES INTO HOST CHROMOSOMES (via crossing over), becomes a prophage, and can reproduce (when a cell divides) WITHOUT DESTROYING the cell.

Answer 24

Lysogenic

Question 25

It can become lytic in response to ENVIRONMENTAL TRIGGERS.

Answer 25

Lysogenic Viruses

Question 26

PHAGES that CAN REPLICATE in both ways is called?

Answer 26

Temperate

Question 27

Types of Baltimore that usually must ENTER THE HOST NUCLEUS BEFORE it is able to replicate.

Examples:
- ADENOVIRUSES, HERPESVIRUSES, AND POXVIRUSES

Answer 27

Class 1: dsDNA virus

Question 28

Types of Baltimore that they REPLICATE WITHIN NUCLEUS and form a ds DNA intermediate during replication

Examples:
- PARVOVIRUS

Answer 28

Class 2: ss DNA virus

Question 29

Types of Baltimore that DO NOT RELY ON HOST POLYMERASES for replication to the extent that viruses with DNA genomes do.

Examples:
- REOVIRUSES & BIRNAVIRUSES

Answer 29

Class 3: dsRNA

Question 30

Types of Baltimore that can be DIRECTLY ACCESSED BY THE HOST RIBOSOMES to immediately form proteins

Examples:
- PICORNAVIRUSES & TOGAVIRUSES

Answer 30

Class 4: Positive sense: ssRNA virus

Question 31

Viruses containing NON-SEGMENTED GENOME for which the genes CANNOT
be directly accessed by host ribosomes.

Examples:
- ORTHOMYXOVIRUSES & RHABDOVIRUSES

Answer 31

Class 5: Negative sense: ss RNA

Question 32

It reverse transcriptase and integrase.

Examples:
- RETROVIRUSES

Answer 32

Class 6: Positive sense: ss RNA

Question 33

It replicates through an ss RNA intermediate.

Examples:
- HEPADNAVIRUSES

Answer 33

Class 7: ds DNA

Question 34

Viral activity causes the CELL TO RELEASE:

Answer 34

Toxins

Question 35

UPTAKE OF NAKED, foreign DNA

Answer 35

Transformation

Question 36

Bacteriophages TRANSFER bacterial genes between hosts accidentally.

Answer 36

Transduction

Question 37

It direct transfer of genes via a pilus or “MATING BRIDGE”.

Answer 37

Conjugation

Question 38

It carries resistance genes that code for enzymes that specifically DESTROYS ANTIBIOTICS. Many also carry genes that code for pili to allow conjugation.

Answer 38

R-Plasmids