Chapter 8: Infectious Agents and Health

Question 1

__________ are tiny non-living particles that need a host cell to reproduce.

Answer 1

Viruses

Question 2

__________ are living, single-celled organisms that can be helpful or harmful.

Answer 2

Bacteria

Question 3

__________ are complex organisms like molds and yeasts that can cause infections.

Answer 3

Fungi

Question 4

__________ live on or in a host and get nutrients at the host’s expense.

Answer 4

Parasites

Question 5

The human body’s natural defense system is called the __________.

Answer 5

immune system

Question 6

Viruses must invade a __________ to reproduce.

Answer 6

host cell

Question 7

Antibiotics are used to treat infections caused by __________.

Answer 7

bacteria

Question 8

Antifungal medicines are used to treat infections caused by __________.

Answer 8

fungi

Question 9

__________ like lice and ticks live on the outside of the body.

Answer 9

Ectoparasites

Question 10

A __________ infection can cause athlete’s foot or ringworm.

Answer 10

fungal

Question 11

__________ is a disease caused by a parasite transmitted by mosquitoes.

Answer 11

Malaria

Question 12

Washing your hands helps prevent the spread of __________ agents.

Answer 12

infectious

Question 13

__________ is a medicine that helps your immune system prevent infections.

Answer 13

Vaccine

Question 14

Tapeworms and roundworms are types of __________.

Answer 14

Helminths

Question 15

Fungi grow best in __________, moist environments.

Answer 15

warm

Question 16

Bacteria reproduce by dividing into __________ cells.

Answer 16

two

Question 17

Giardia is a parasite that affects the __________ system.

Answer 17

digestive

Question 18

A __________ is a red, circular fungal infection on the skin.

Answer 18

Ringworm

Question 19

Sneezing without covering your mouth can help spread __________.

Answer 19

viruses

Question 20

The flu is caused by a __________.

Answer 20

virus

Question 21

Vaccines help the __________ system recognize and fight infections.

Answer 21

immune

Question 22

Ticks can spread diseases like __________.

Answer 22

Lyme disease

Question 23

Sharing food and drinks can spread __________ agents.

Answer 23

infectious

Question 24

Malaria is caused by a type of __________ parasite.

Answer 24

protozoan

Question 25

Some bacteria in the digestive system help us __________ food.

Answer 25

digest

Question 26

Cooking meat thoroughly can help prevent __________ infections.

Answer 26

parasitic

Question 27

Which of the following is NOT a living organism? A. Bacteria B. Fungi C. Virus D. Parasite

Answer 27

C. Virus — Viruses are not living organisms because they cannot reproduce or grow on their own.

Question 28

Which infectious agent causes the common cold? A. Bacteria B. Virus C. Fungus D. Parasite

Answer 28

B. Virus — The common cold is caused by viruses, not bacteria or fungi.

Question 29

What medicine is used to treat bacterial infections? A. Antivirals B. Antibiotics C. Vaccines D. Antifungals

Answer 29

B. Antibiotics — Antibiotics kill bacteria or stop them from growing.

Question 30

Which condition is caused by a fungus? A. Strep throat B. Athlete’s foot C. Malaria D. The flu

Answer 30

B. Athlete’s foot — This is a common fungal infection.

Question 31

How do viruses reproduce? A. By binary fission B. On their own in the air C. By using a host cell D. Through photosynthesis

Answer 31

C. By using a host cell — Viruses need a host cell to make copies of themselves.

Question 32

What do parasites need to survive? A. Water only B. Host organism C. Light D. Oxygen only

Answer 32

B. Host organism — Parasites depend on hosts for food and shelter.

Question 33

Which of these is a type of ectoparasite? A. Tapeworm B. Giardia C. Tick D. Ringworm

Answer 33

C. Tick — Ticks live on the outside of the body and are ectoparasites.

Question 34

What is a common way bacteria spread? A. Shouting B. Photosynthesis C. Contaminated food D. Loud music

Answer 34

C. Contaminated food — Harmful bacteria often spread through spoiled or contaminated food.

Question 35

Which of the following infections is treated with antifungals? A. The flu B. Ringworm C. Strep throat D. Malaria

Answer 35

B. Ringworm — Ringworm is a fungal infection that affects the skin.

Question 36

What is the main purpose of a vaccine? A. Cure diseases B. Replace antibiotics C. Prevent infection D. Kill fungi

Answer 36

C. Prevent infection — Vaccines prepare the immune system to fight infections.

Question 37

Which infectious agent is spread by mosquitoes and causes malaria? A. Virus B. Fungus C. Protozoan D. Bacterium

Answer 37

C. Protozoan — Malaria is caused by a protozoan parasite carried by mosquitoes.

Question 38

Which of these is caused by a bacterium? A. Strep throat B. Athlete’s foot C. Ringworm D. COVID-19

Answer 38

A. Strep throat — This illness is caused by bacteria like Streptococcus.

Question 39

Where do fungi grow best? A. Dry and cold areas B. Moist and warm areas C. Bright sunny places D. High altitudes

Answer 39

B. Moist and warm areas — Fungi grow best in environments that are both warm and moist.

Question 40

How do bacteria reproduce? A. Through seeds B. Using host DNA C. Splitting into two cells D. Budding from fungi

Answer 40

C. Splitting into two cells — Bacteria reproduce by dividing in half, also called binary fission.

Question 41

What is Giardia? A. A virus B. A bacterium C. A fungus D. A parasite

Answer 41

D. A parasite — Giardia is a protozoan parasite that affects digestion.

Question 42

What does the immune system do? A. Helps digest food B. Circulates blood C. Fights off infections D. Makes energy

Answer 42

C. Fights off infections — The immune system protects the body from disease.

Question 43

Which of these is used to treat parasitic infections? A. Antivirals B. Antibiotics C. Antiparasitics D. Antifungals

Answer 43

C. Antiparasitics — These medicines are used to kill or remove parasites.

Question 44

How do vaccines help your body? A. They directly kill bacteria B. They boost your immune system C. They increase hunger D. They improve digestion

Answer 44

B. They boost your immune system — Vaccines help your immune system recognize specific germs.

Question 45

What are helminths? A. Microscopic fungi B. Protozoa C. Parasitic worms D. Bacterial toxins

Answer 45

C. Parasitic worms — Helminths are large worms that infect humans and animals.

Question 46

What spreads Lyme disease? A. Fleas B. Mosquitoes C. Ticks D. Dust

Answer 46

C. Ticks — Ticks can spread bacteria that cause Lyme disease.

Question 47

What’s one way to prevent the spread of parasites? A. Drinking untreated water B. Walking barefoot C. Washing hands D. Sharing food

Answer 47

C. Washing hands — Good hygiene helps prevent the spread of many parasites.

Question 48

Why don’t antibiotics work on viruses? A. Viruses are too large B. Viruses reproduce differently C. Antibiotics target fungi only D. Viruses clean the body

Answer 48

B. Viruses reproduce differently — Antibiotics only target bacterial structures, not viruses.

Question 49

Which is a helpful use of bacteria? A. Causing illness B. Cleaning wounds C. Digesting food D. Creating parasites

Answer 49

C. Digesting food — Some bacteria in your gut help break down food.

Question 50

What is ringworm? A. A bacterial rash B. A viral fever C. A fungal infection D. A worm infection

Answer 50

C. A fungal infection — Despite the name, ringworm is caused by a fungus.

Question 51

Which body system fights off infections? A. Skeletal B. Immune C. Digestive D. Respiratory

Answer 51

B. Immune — The immune system helps your body detect and destroy pathogens.