Viruses

Question 1

what is a virus

Answer 1

tiny non cellular structures

Question 2

are viruses living things

Answer 2

not classified as living however they show some living featuress

Question 3

compare their living and non living features

Answer 3

living:
contain genetic material
have a protein coat
can replicate (inside a living cell)

non living:
non cellular
need a live host to replicate
have no organelles or metabolism outside their host

Question 4

structure

Answer 4

core of nucleic acid (either DNA or RNA NEVER both)
a capsid on its surface

Question 5

what is a capsid

Answer 5

a coat of proteins

Question 6

what are the 3 classifications of a virus

Answer 6

round, rod or complex

Question 7

bacteriophage

Answer 7

a virus that infects bacteria cells

Question 8

what is an obligate parasite

Answer 8

an organism that cannot replicate by itself and needs to use the energy and structures of a live host.

Question 9

process of virus replication

Answer 9

1. attachment- proteins on virus attach to special receptors in host cells
2. entry- virus forms a hole in host cell and nucleic acid is inserted into host cell
3. synthesis- host cell nucleic acid is inactivated. the virus uses the hosts organelles to produce copies of the viral proteins and viral DNA or RNA
4. assembly- new virus are assembled in host cell

5- new virus is released by the lysis of the host cell

Question 10

disadvantages of viruses

Answer 10

1. human disease- common cold, influenza, measles, mumps, ect
2. plant diseases- tobacco mosaic disease, potatos mosaic disease
3. animal disease- foot+mouth, rabies, cowpox

Question 11

advantages of viruses

Answer 11

genetic engineering- viruses used as vectors thst carry genes from source to host cell
infection control- bacteriophages can be used to control bacterial infections

Question 12

why cant antibiotics treat viral infections such as the flu?

Answer 12

they treat bacterial infections and will have 0 effect of any viral infection