IV

Question 1

close association between two or more organisms

Answer 1

Symbiosis

Question 2

neither partner is harmed, and both can live independently

Answer 2

Commensalism

Question 3

both partners benefit, obligatory association

Answer 3

Mutualism

Question 4

obligatory for the parasite, harmful to the host

Answer 4

Parasitism

Question 5

an organism that feeds, grows, and is sheltered on or in a host without contributing to the host’s survival

Answer 5

Parasite

Question 6

segmented bodies (head, thorax, abdomen), paired appendages (antennae, wings, legs)

Answer 6

Arthropods

Question 7

parasitic worms (flukes, tapeworms, nematodes)

Answer 7

Helminths

Question 8

provides nourishment for a parasite

Answer 8

Host

Question 9

harbors adult (sexually mature) parasites

Answer 9

Final/definitive host

Question 10

harbors asexual stages, obligatory for the parasite’s life cycle

Answer 10

Intermediate host

Question 11

harbors infection but shows no signs, acts as a source of infection

Answer 11

Reservoir Host

Question 12

acts as a carrier, parasite does not develo

Answer 12

Paratemic/transport host

Question 13

development of a parasite through its various forms

Answer 13

Life cycle

Question 14

marked change in appearance, structure, and habits during growth and development

Answer 14

Metamorphosis

Question 15

organism with both male and female reproductive organs

Answer 15

Hermaphrodite

Question 16

tough, resistant, inert covering (nematodes, arthropods)

Answer 16

Cuticle

Question 17

within a fibrous tissue capsule made by the host

Answer 17

Encapsulated

Question 18

within a cyst secreted by the parasite

Answer 18

Encysted

Question 19

live within the host’s body

Answer 19

Internal Parasites (Endoparasites)

Question 20

Trypanosoma evansi, Theileria annulata, Babesia bigemina, Toxoplasma gondii, Eimeria spp*

Answer 20

Protozoa

Question 21

Trematodes (flukes), Cestodes (tapeworms), Nematodes (roundworms, hookworms)

Answer 21

Worms(helminths)

Question 22

live on the host’s surface or skin

Answer 22

External Parasites (Ectoparasites):

Question 23

General Clinical Signs of Parasitism

Answer 23

Anorexia
* Retarded growth
* General weakness
* Coughing
* Rough hair coat
* Rapid weight loss
* Persistent bloody diarrhea
* Death

Question 24

General Clinical Signs of Parasitism

Answer 24

Anorexia
* Retarded growth
* General weakness
* Coughing
* Rough hair coat
* Rapid weight loss
* Persistent bloody diarrhea
* Death

Question 25

Factors Affecting Parasitism*

Answer 25

Parasite reproductive capacity * Number of parasites * Host immune resistance * Climate and season * Cattle management practices

Question 26

* Eukaryotic, multicellular * Cylindrical and tapered * Complete digestive system * Mostly dioecious (separate sexes) * Males smaller with spicules * Free-living or parasitic * Live in the host for most of their lives * Examples: *Ascaris, hookworms,

Answer 26

Nematodes (roundworms)

Question 27

* Flat, leaf-shaped bodies * Ventral and oral suckers * Absorb food through cuticle * Named after host tissue where they reside (e.g., lung fluke, liver fluke)

Answer 27

Trematoda (flukes)

Question 28

* Intestinal parasites * **Scolex** (head) with suckers, sometimes hooks * Absorb food through cuticle * Body consists of **proglottids** (segments with reproductive organs)

Answer 28

Cestodes (tapeworms)

Question 29

Life cycle of trematodes

Answer 29

Egg Miracidia Sporocyst Redia Cercaria Metacercaria

Question 30

Life cycle of cestodes

Answer 30

Egg Oncosphere Cysticersi

Question 31

* Jointed legs * Invertebrates * Exoskeleton * Segmented body * Paired appendages

Answer 31

Arthropods

Question 32

* Eukaryotic, multicellular * Head, thorax, abdomen * Head: eyes, antennae, mouthparts * Thorax: legs, wings * Most flies (Diptera) have two wings, lice (Mallophaga and Anoplura) and fleas (Siphonaptera) are wingless

Answer 32

Class insecta

Question 33

* Eukaryotic, multicellular * Subclass Acari (mites and ticks) * Larvae have three pairs of legs, nymphs and adults have four pairs * Fused head, thorax, abdomen; no antennae or mandibles * Mouthparts form a **capitulum**

Answer 33

Class arachnida

Question 34

* Eukaryotic, multicellular * Subclass Acari (mites and ticks) * Larvae have three pairs of legs, nymphs and adults have four pairs * Fused head, thorax, abdomen; no antennae or mandibles * Mouthparts form a **capitulum**

Answer 34

Class arachnida

Question 35

Eukaryotic, unicellular * Some have organs of locomotion (flagella, cilia, pseudopods)

Answer 35

Protozoa