VIRUSES Viruses – are segments of nucleic acids contained in a protein coat; they are not cells; they are smaller than prokaryotes and range in size from.

Slides:



Advertisements
Similar presentations
Chapter 20 Viruses and Bacteria Section 1: Viruses Section 2: Bacteria.
Advertisements

Section 2: Viruses Preview Bellringer Key Ideas Is a Virus Alive?
Unit 5: Classification and Kingdoms
In what kingdom do we classify a virus? None! Viruses are not considered living, so we do not classify them with living organisms.
HAPPY THURSDAY Bellwork: What is a virus? How do viruses make us sick? How are viral infections treated? Can viral infections be prevented? Write 37 words.
Viruses. Is a Virus a Living Organism? Chapter 1 – Properties of life –Cellular Respiration –Reproduction –Metabolism –Homeostasis –Heredity –Responsiveness.
Viruses Are they alive?. The properties of life ● You already know that living things: 1. Made of cells 2. Grow and reproduce 3. Use information from.
Monday 4/13/2015 Virus & Bacteria Agenda: Activity: Brain Pop
Viruses More free powerpoints at
Viruses. Virus A non living particle composed of a nucleic acid and a protein coat A non living particle composed of a nucleic acid and a protein coat.
Viruses. Nonliving particle – do not contain all characteristics of life Reproduce by infecting cells Made of 2 things Nucleic acid Capsid – protein coat.
VIRUS Notes. Definition Viruses are tiny particles unlike any other organism. A virus consists of genetic material such as RNA or DNA wrapped in a protein.
Viruses Living or Not ???????. Characteristics of Viruses Among the smallest biological particles that are capable of causing diseases in living organisms.
Viruses Ch. 20. Is a Virus Alive? Lets first look at organisms we know are alive? What can you tell by comparing the virus to the cells we have learned.
Viruses.
Viruses: Key Ideas Why is a virus not considered a living organism?
Warm-Up What makes something alive? Is the common cold a virus or a bacteria? When is your project (Data Table and Graphs) due?
11.2 Viruses.
Viral Cycles: Lytic Lysogenic
Doesn’t belong to any kingdom -It’s not a plant or an animal. -It’s not a fungi, protist, or bacteria. WHAT IS A VIRUS?
Viruses, bacteria, viroids, and prions can all cause infection.
Viruses. Virus: Segments of nucleic acid (DNA OR RNA) within a protein coat (noncellular); NONLIVING; much smaller then prokaryotes Must reproduce within.
1 Zoology 145 course General Animal Biology For Premedical Student H Zoology Department Lecture 3 : Viruses.
18.2 Viral Structure and Reproduction TEKS 4C The student is expected to: 4C Compare the structures of viruses to cells, describe viral reproduction, and.
Viruses. Tiny 1/2 to 1/100 the size of smallest bacterium Nonliving Do not fulfill the criteria for life Do not carry out respiration, grow or move Can.
Viruses Biology 4C : compare the structures of viruses to cells, describe viral reproduction, and describe the role of viruses in causing diseases such.
Viruses.
Viruses Page 328.
Viruses.
Viruses 5/26/2018.
Viruses Chapter
Wednesday/Thursday 4/13-4/14/2016
Viruses.
What is a virus? Tiny organisms that may lead to mild to severe illnesses in humans, animals, and plants.
Section 2: Viruses.
Day 1.
Viruses Medical ppt
Viruses Chapter
Chapter 18 Studying Viruses and Prokaryotes
Viruses.
Pathogens They’ve Gone Viral !!!
Viruses
Viruses.
Viruses Essential Questions: What is the structure of a virus and how do viruses cause infection?
VIRUSES Viruses – are segments of nucleic acids contained in a protein coat; they are not cells; they are smaller than prokaryotes and range in size.
Pathogens They’ve Gone Viral !!!
Standard SB3d: Compare and contrast viruses with living organisms.
Viruses.
The student is expected to: 4C compare the structures of viruses to cells, describe viral reproduction, and describe the role of viruses in causing diseases.
General Animal Biology
Viruses Review.
Viruses.
Viruses
KEY CONCEPT Viruses exist in a variety of shapes and sizes.
Are Viruses Alive?.
Viruses Viruses – are segments of nucleic acids
Chapter 15 Viruses.
To be considered living…
Viruses.
KEY CONCEPT Viruses exist in a variety of shapes and sizes.
Viruses Slow motion sneezing (1:36 min) Zika Virus Ebola 1.
Arianna K. Olivia J. Willow G.
VIRUSES Viruses – are segments of nucleic acids contained in a protein coat; they are not cells; they are smaller than prokaryotes and range in size.
Did you wash your hands today?
Viruses Page 328.
Virus A pathogen that consists of a Nucleic Acid – (DNA or RNA) wrapped in a Protein Coat- (Capsid). Classification: Classified by the host Bacteriophage.
Viruses Page 328.
VIRUSES Viruses – are segments of nucleic acids contained in a protein coat; they are not cells; they are smaller than prokaryotes and range in size.
Viruses Alive? Or Not?.
Viruses Viruses – are segments of nucleic acids
Presentation transcript:

VIRUSES Viruses – are segments of nucleic acids contained in a protein coat; they are not cells; they are smaller than prokaryotes and range in size from 20nm to 250 nm

Is A Virus Alive? NO, viruses do not have all the properties of life, so biologists do not consider them to be living; viruses do not grow, do not have homeostasis, and do not metabolize Viruses are pathogens – agents that cause disease; they replicate by infecting cells and using the cell to make more viruses

Viral Structure: capsid– the virus protein coat; may contain either RNA or DNA, but not both envelope – viral membrane; it helps the virus enter cells; it consists of protein, lipids, and glycoproteins nucleic acid – DNA or RNA RNA viruses: HIV (Human Immunodeficiency Virus), Influenza, rabies DNA viruses: warts, chickenpox, mononucleosis

Viral Structure Glycoprotein used to attach to surface of cell

Viral Shapes Rod Helix Polyhedral   Sphere Complex

Viral Reproduction: Viruses lack enzymes necessary for metabolism and have no structures to make proteins. Viruses must rely on living cells (host cells) for replication. *How do viruses enter a cell? Plant cell – through tiny tears in the cell wall Animal cell - by endocytosis Bacteria – it punches a hole in the bacterial wall and injects its DNA into the cell

Once inside a cell, the virus can take one of two different paths: the lytic cycle or the lysogenic cycle. lytic cycle – is the cycle of viral infection, replication, and cell destruction lysogenic cycle – the viral gene is inserted into the host chromosome and whenever the cell divides, the viral gene is copied resulting in 2 infected host cells; a change in the environment can cause the viral gene to begin the lytic cycle ex: cold sores/fever blisters – the virus hides deep in the nerves of the face; when conditions in the body became favorable, such as when a person is under stress, the virus begins to cause tissue damage

Lytic vs. Lysogenic Cycle