Infectious Disease Biology pgs

Objectives Identify the causes of disease. Explain how infectious diseases are transmitted Describe how antibiotics fight infection.

A ________________is any change, other than an injury, that disrupts the normal functions of the body. Disease-causing agents are called___________________. Diseases caused by pathogens are called infectious diseases. disease pathogens

Agents of Disease Pathogens that can cause disease include: ____________________ bacteria protists worms fungi Viruses Viruses are tiny particles that __________________and replicate within living cells. Viruses attach to a cell’s surface, insert their genetic material, and take over many of the functions of the host cell. viruses invade

Viruses can infect nearly every type of organism. Diseases caused by viruses include the common cold,_______________________, and smallpox. Bacteria Most bacteria are ________________________to humans. influenza harmless

Protists Disease-causing ______________________are transported from person to person by: mosquitoes (malaria) insects (African sleeping sickness) contaminated water supplies (amebic dysentery). Worms Flatworms and roundworms cause many human diseases. Other parasitic worms include Schistosoma, ___________________and hookworms. protists tapeworms

Fungi ____________________can infect the outer layers of the skin on the feet (athlete’s foot) or the scalp (ringworm). Some infectious diseases are spread from one person to another through coughing,_______________________, or physical contact. Still others are spread by infected__________________. Fungi sneezing animals

Physical Contact Some infectious diseases can be spread by direct________________ contact. Some dangerous pathogens are spread by sexual contact. Most diseases spread by indirect contact, such as through the air. Some behaviors can help to control transmission of diseases spread by physical contact. Cover your _____________________when you sneeze or cough. Wash your ___________________thoroughly with soap and warm water often. physical mouth hands

Contaminated Food and Water Food poisoning is caused by eating food that has_________________. Bacteria are always present in uncooked meat. Contaminated water also causes disease, especially in areas with poor sanitation and untreated sewage. Infected Animals Animals also spread infectious disease. Animals that carry pathogens from person to person are called_________________________. pathogens vectors

Fighting Infectious Diseases _____________________________are compounds that kill bacteria without harming the cells of the human or animal hosts. They work by interfering with cellular processes of microorganisms. Antibiotics have no effect on viruses. Antiviral drugs have been certain viral diseases. Antibiotics