Week 4

VIRUSES

Quarter 2 Week 4

Announcements

Viruses come in many shapes and sizes

What is a Virus?

NON-LIVING

ARE MADE OF DNA or RNA surrounded by a protein coat

NOT MADE OF CELLS

CAN evolve and mutate to disrupt cells

CAN'T REPRODUCE ON THEIR OWN

How do viruses attack cells?

Viruses can infect a variety of organisms

Bacteria

Plants

Animals

What does a plant viral infection look like?

The FLU epidemic

The most common virus in human populations is Influenza, or flu.

An epidemic is an outbreak of a disease within a population of people during a specific time.

Examples of viruses

Disease

- Can happen when viruses kill cells, but they don't always cause cell death. - Homeostasis is disrupted in the host cell, which causes illness.

pandemics

A pandemic is an epidemic that spreads through human populations across a large region or even worldwide.

Every year in the United States, about 36,000 people die from the flu. Flu pandemics can kill millions of people.

Epidemiologists

When a disease breaks out, scientists called epidemiologists investigate the outbreak, looking for its cause. Epidemiologists are like detectives trying to solve a crime. The information epidemiologists learn is important to understand the pathogen, and help prevent future outbreaks of disease.

zoonosis

-A deadly strain of avian flu virus named H5N1 has posed the greatest risk for a new influenza pandemic. -A disease that can be spread from animals to humans is called a zoonosis.

Slowing the spread of viruses

• Stay home if you are sick (social distance).

• Wear a mask to catch droplets from coughs.
• Wash your hands with soap and warm water for 20 seconds to kill germs.

Spread of Viral Disease

The best way to stop the spread of a disease is to educate the community. Most viruses are spread through the air in sneezes or coughs, but they can also spread in saliva, sweat and blood.

ENJOY!

ONE KIND ACT A DAY!

HAVE A GREAT THANKSGIVING BREAK!

Viruses inject their genetic material into a host cell. Once inside, the cell’s own ATP (energy), ribosomes, and enzymes are used to make copies of the virus.