TEKS B.4C Viruses

Which of the following statements accurately describes a

difference between viruses and bacteria?

• Viruses are much smaller than bacteria cells.

• Viruses have a higher metabolism than bacteria cells.

• Viruses contain organelles while bacteria cells do not.

• Viruses reproduce asexually while bacteria cells reproduce

  sexually.

Norovirus outbreaks have caused many schools to close.

Norovirus causes extreme vomiting within as little

of 12 hours of exposure. The virus is spread in the air as infected individuals vomit. Based on this information, which reproductive cycle does norovirus most likely undergo?

• Mitosis

• Meiosis

• Lytic Cycle

• Lysogenic Cycle

Identify the virus(es) in the above diagram.

• I

• IV, V

• II, V

• II, IV, V

• I, III

Most viruses have the structural arrangement of —

• a cell wall surrounding the cell membrane

• a capsid shell made from lipids

• flagella surrounding the cell membrane

• a capsid surrounding a nucleic acid sequence

What structure is found in viruses but not in cells?

• RNA
• Proteins
• Capsid
• DNA

What structure is most likely found in both viruses and cells? 

• Ribosomes
• Proteins
• Cytoplasm
• Vacuoles

Observe the virus and cell pictures above. Each has

projections that extend beyond the main

structure. How are these projections used differently in

viruses and protists?

• Viruses use projections to move throughout their host while

  protists use projections to attach to other cells.

• Viruses use projections to attach to cells while protists use

  projections to move through their environment.

• Viruses use projections to defend against the immune system

  while protists use projections to eat.

• DViruses use projections to allow substances to pass through

  the main structure while protists use projections for protection.

Cold sores are caused by a lysogenic virus known as herpes simplex II (HSV-2). This virus causes cold sores around the mouth and can be

spread by contact such as kissing or sharing eating utensils. What accounts for the fact that someone with HSV-2 will occasionally have cold sores for the rest of their life?

• Once a person has contracted HSV-2, it is easier for

  them to contract it again.

• Copies of the HSV-2 virus genome are maintained in the genomes of the host cells.

• HSV-2 causes mutations in the cells in and around the mouth

  that code for cold sores.

• HSV-2 destroys immune system cells, making it harder for

  the body to fight off infection.

Viruses that attack humans are very well known. Viruses also attack and infect bacteria. What is the name of a virus that infects bacteria?

• capsid

• glycoprotein

• phage

• viroid

A virus has infected a bacteria and inserted its viral DNA into the DNA of the bacterial chromosome. This inserted viral DNA is known as what?

• vDNA
• vNA
• Prophage
• Provirus