Lecture 14 - Cell Diversity and Viruses

Question 1

a dynamic INFORMATION system

Answer 1

The GENOME

Question 2

Cells arise from DIVISION of

Answer 2

pre-existing cells

Question 3

Cell function is dependent on ______ reactions occurring in _______

Answer 3

chemical, compartments

Question 4

thecell Contains a large number of

Answer 4

components

Question 5

components are organized with respect to

Answer 5

time and space

Question 6

Fidelity of interactions is
maintained through

Answer 6

control of regulation of
components

Question 7

cellular activities are very

Answer 7

precise

Question 8

Bacteria, archaea
Structurally simpler

Answer 8

Prokaryotic cells

Question 9

Protists, fungi, plants, animals
Structurally more complex

Answer 9

Eukaryotic cells

Question 10

Protista are enormously

Answer 10

diverse

Question 11

Protista charactaristics

Answer 11

Mostly unicellular
* Mostly aquatic
* Often contain flagella or cilia
* Sexual and asexual reproduction
* Diverse nutrition lifestyles
– Photosynthetic, holotrophic,
saprotrophic, parasitic, symbiotic

Question 12

Link between prokaryotes and eukaryotes
(Examples:)

Answer 12

• Protozoans - malaria
  – Unicellular red and green algae
  – Diatoms
  – Slime molds 9

Question 13

Slime molds were originally classified as

Answer 13

part of the Fungi kingdom, but now grouped with the kingdom Protista—it’s not a mold

Question 14

Slime Molds Unique Characteristics

Answer 14

• Eukaryotic single cell organism.
• Use a primitive form of sexual reproduction (spores).
• Size: less than 1 cm to several square metres.
• Multinucleate (1 cell has 1000s of nuclei).
• They have an amazing capacity to move around and respond to their environment.

Question 15

Viruses have many

Answer 15

Families and Subtypes

Question 16

Virosphere:
Around_____species of mammals and about ______ species of vascular plants have
been described.

Answer 16

5,500, 391,000

Question 17

Virosphere:

the ______ the organism, the ______ the numbers typically get

Answer 17

smaller, higher

Question 18

There are _______
to _______ species of arthropod (invertebrate animals) and probably more than_____ distinct fungi

Answer 18

1 million, 10 million, 5.1 million

Question 19

as many as ______ distinct microbes on
Earth

Answer 19

1.6 million

Question 20

Since each _____/____ ____ is almost certainly associated with at least ____ _____, then there are probably millions of ______ _______

Answer 20

microbe/cell type, one virus, distinct viruses

Question 21

So far, just ____ _____ _____ have been formally described.

Answer 21

4,958 virus species

Question 22

Viruses are not

Answer 22

cells

Question 23

Viruses are __________ packages that can function and reproduce only within
_____ _____

Answer 23

macromolecular, living cells

Question 24

Outside of cells, viruses exist as

Answer 24

inanimate particles called VIRIONS.

Question 25

Viruses: How do they compare to cells?

Answer 25

1. Highly COMPLEX and ORGANIZED yes 2. Activity controlled by a GENETIC program. yes 3. Can REPRODUCE—make copies of themselves. yes and no 4. Assimilate and utilize ENERGY. no 5. Carry out many CHEMICAL reactions (enzymes). no 6. Engage in MECHANICAL activities. no 7. Respond to STIMULI. 8. Capable of SELF REGULATION. no 9. They EVOLVE. yes

Question 26

Protein coat that surrounds nucleic acid

Answer 26

capsid

Question 27

Enclosed in a protein- containing membrane or not

Answer 27

enveloped or unenveloped

Question 28

Nucleic acid either RNA or DNA encodes

Answer 28

viral proteins, Thus, either RNA or DNA viruses

Question 29

Baltimore classification

Answer 29

categorizes viruses based on type of genome (RNA/DNA) and their method of replication.

Question 30

HIV is an example of

Answer 30

retrovirus

Question 31

retrovirus is an

Answer 31

a RNA virus that can insert a copy of its genome into the DNA of a host cell. Causes Acquired Immunodeficiency Syndrome (AIDS)

Question 32

Hepatitis B is a member of the

Answer 32

hepadnavirus family (DNA type). Affects human liver and cause serious infections

Question 33

Ebola virus is part of the

Answer 33

filoviruses family

Question 34

filoviruses family encodes

Answer 34

the genome in the form of single-stranded negative-sense RNA. Cause hemorrhagic fever

Question 35

Adenoviruses are a group of viruses that can cause

Answer 35

respiratory illnesses (e.g., bronchitis or pneumonia) or conjunctivitis (an infection in the eye).

Question 36

Bacteriophage is a virus that infects and replicates

Answer 36

within bacteria and archaea

Question 37

TMV was one of the first viruses to be characterized (name it)

Answer 37

tobacco mosaic virus

Question 38

As a way to battle the continuous attacks from bacteriophages, bacteria have evolved an

Answer 38

immune-like system called CRISPR-Cas

Question 39

Viruses bind to a cell surface via

Answer 39

specific proteins and then enter into the cell

Question 40

This defines the cell type(s) the virus can infect and the

Answer 40

host range

Question 41

NARROW host range like human cold and influenza viruses infect

Answer 41

epithelial cells of human respiratory system.

Question 42

WIDE host range like rabies can infect

Answer 42

cells in dogs, foxes, bats, raccoons, and humans

Question 43

Once inside a cell, the ____ hijacks _____ ______ to synthesize ______ _____ (DNA/RNA) and______

Answer 43

virus, cellular machinery, nucleic acids, proteins

Question 44

These parts are then assembled to make new

Answer 44

virus particles to infect other cells

Question 45

Two main types of viral life cycle

Answer 45

NON-LYTIC (also known as LYSOGENIC) and LYTIC

Question 46

NON-LYTIC characteristics

Answer 46

– Viral nucleic acid is replicated in the host; viral proteins produced – Virus reproduces without destroying the host cell

Question 47

LYTIC

Answer 47

– Production of virus particles ruptures (and kills) host cell (e.g., bacteriophages; ebola virus)

Question 48

A combination of both lysogenic and

Answer 48

lytic life cycles are often found

Question 49

Infected cell can survive, often with

Answer 49

impaired function (e.g., HIV, Chicken Pox).

Question 50

The rabies virus has an enveloped....

Answer 50

single stranded RNA genome

Question 51

The RNA genome encodes five genes

Answer 51

nucleocapsid protein (N), phosphoprotein (P), matrix protein (M), glycoprotein (G) and the viral RNA polymerase (L)

Question 52

COVID-19 can affect the

Answer 52

upper respiratory tract (sinuses, nose, and throat) and the lower respiratory tract (windpipe and lungs)

Question 53

The lungs are the organs most affected by COVID-19 because the virus accesses

Answer 53

host cells via the enzyme angiotensin-converting enzyme 2 (ACE2), which is most abundant in type II alveolar cells of the lungs.

Question 54

Papovavirus

Answer 54

a large family of viruses that includes the human papillomavirus (HPV)

Question 55

RNA vaccines work by tricking the body’s cells into producing

Answer 55

a fragment of a virus, an antigen, from an RNA template

Question 56

One strategy to make RNA vaccines more effective at lower doses — or in a single dose — is to incorporate the instructions for

Answer 56

assembling a replicase, which can make lots of copies of the RNA template for producing antigens