Chapter 13 - Characteristics of Viruses Cause many...

Info iconThis preview shows pages 1–15. Sign up to view the full content.

View Full Document Right Arrow Icon
Characteristics of Viruses • Cause many infections of humans, animals, plants, and bacteria • Cannot carry out any metabolic pathway • Neither grow nor respond to the environment • Cannot reproduce independently • Recruit the cell’s metabolic pathways to increase their numbers
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Characteristics of Viruses Cause most of the diseases that plague the industrialized world Virus – miniscule, acellular, infectious agent having one or several pieces of either DNA or RNA No cytoplasmic membrane, cytosol, organelles Have extracellular and intracellular state
Background image of page 2
Characteristics of Viruses Extracellular State – Called virion – Protein coat (capsid) surrounding nucleic acid – Nucleic acid and capsid also called nucleocapsid – Some have phospholipid envelope – Outermost layer provides protection and recognition sites for host cells Intracellular State – Capsid removed – Virus exists as nucleic acid
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Characteristics of Viruses [INSERT FIGURE 13.1]
Background image of page 4
Characteristics of Viruses Genetic Material of Viruses – Show more variety in nature of their genomes than do cells – May be DNA or RNA, but never both – Primary way scientists categorize and classify viruses – Can be dsDNA, ssDNA, dsRNA, ssRNA – May be linear and composed of several segments or single and circular – Much smaller than genomes of cells
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Characteristics of Viruses [INSERT FIGURE 13.2]
Background image of page 6
Characteristics of Viruses Hosts of Viruses – Most viruses infect only particular host’s cells • Due to affinity of viral surface proteins or glycoproteins for complementary proteins or glycoproteins on host cell surface – May be so specific they only infect particular kind of cell in a particular host – Generalists – infect many kinds of cells in many different hosts
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Characteristics of Viruses [INSERT FIGURE 13.3]
Background image of page 8
Characteristics of Viruses [INSERT FIGURE 13.4]
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Characteristics of Viruses Capsid Morphology – Capsids – protein coats that provide protection for viral nucleic acid and means of attachment to host’s cells – Capsid composed of proteinaceous subunits called capsomeres – Some capsids composed of single type of capsomere; others composed of multiple types
Background image of page 10
Characteristics of Viruses [INSERT FIGURE 13.5]
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Characteristics of Viruses [INSERT FIGURE 13.6]
Background image of page 12
Characteristics of Viruses [INSERT FIGURE 13.7]
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Characteristics of Viruses The Viral Envelope
Background image of page 14
Image of page 15
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 05/24/2011 for the course BIO 119 taught by Professor Stevendroho during the Spring '11 term at Moraine Valley Community College.

Page1 / 55

Chapter 13 - Characteristics of Viruses Cause many...

This preview shows document pages 1 - 15. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online