CH 18-19

Arthropods play a role in which of the following?

Produce products such as silk and honey Serve as a source of human food. Spread serious diseases.

Which of the following are characteristics of the nervous system of nematodes?

Ring of nerve tissue and ganglia around the pharynx Sensory papillae around the head and tail Small nerves at the anterior end

The _____ are a pair of sensory organs that open on each side of a nematode's head.

aphids

Whip scorpions, mites, and ticks belong to Class ____ within Subphylum Chelicerata.

arachnida

The cuticle of nematodes is primarily composed of the structural protein

collagen

Both the tracheal and excretory systems in spiders and insects are products of _________ evolution.

convergent

Spiders usually precede mating with some type of ____ ritual.

courtship

In some spiders, ____ glands are modified nephridia that open at the base of the first and third walking legs.

coxal

The eight simple eyes in spiders contain which of the following structures?

lens, optic rod, retina

The horseshoe crab found in North America is classified under genus

limulus

The function of a nematode hydrostatic skeleton differs from other invertebrates because the cuticle functions as an antagonist to the ____ muscles.

longitudinal

Select all of the characteristics of horsehair worms (nematomorphs).

longitudinal mucles & cuticle

Ascaris ______ is a nematode that infects human and is considered one of the most common worm parasites of humans.

lumbricoides

Other Demodex species have been known to cause ____ in domestic animals.

mange

Eurypterids and horseshoe crabs belong to _____ within Subphylum Chelicerata

merostomata

Female filarial worms live in the lymphatic system of its host where it releases live young called _____ into the blood and lymphatic system.

microfilariae

In nematodes, a ____ arm extends from each cell body to the _____ or ______ nerve.

muscle & ventral or dorsal

Select all of the subphyla of Arthropoda.

myriapoda hexapoda chelicerata crustacea trilobita

Members of the phylum _____ inhabit tropical and polar climates, can be found in freshwater and salt water, and are parasitic to plants and animals. Although there are 25,000 named species within this phylum, it is estimated that nearly 500,000 species have not been named.

nematoda

The dog heartworm is a _______.

nematode

Some spiders possess coxal glands, which are modified

nephridia

The brown recluse spider venom is hemolytic, whereas the black widow spider venom is ______ in nature.

neurotoxic

In the life cycle of hookworms, a ____ embryo develops into a first-stage ____ , then molts _____ times before infecting a new host.

shelled juvenile two

Select all of the products generated by arthropods.

silk, honey, beeswax, dye

Scorpions have ______ chelicerae and ______ pedipalps, which are modified claws used for feeding.

small: large

A spider's abdominal silk gland is connected to a web-spinning organ called a

spinneret

A scorpion's preabdomen or mesosoma consists of _____ segments while its postabdomen or metastoma consists of _______ segments.

7 & 5

What number of filarial worm species, such as Wuchereria bancrofti, cause diseases in humans?

8 species

The body plan of trilobites consisted of which of the following?

Chitinous exoskelton 3 tagmata compound eyes

Place the steps of a human filarial worm life cycle in order, beginning at the top with production of microfilariae.

Female releases microfilaria mosquito ingests microfilaria Microfilaria mature Mosquito feeds human again

In addition to providing a place of retreat, a spider's silk threads play a role in which of the following?

Nest lining Prey capture Egg sac construction

Select all of the following that are present in Phylum Arthropoda

Marine, freshwater, and terrestrial forms Free-living and parasitic forms Jointed appendages

Select all of the classes within the subphylum Chelicerata.

Merostomata Arachnida Pycnogonida

Scorpions make up approximately ______ species and are distributed worldwide.

1400

The earliest arthropods, trilobites, arose before the Cambrian period and became extinct about ______ years ago.

250 million

There are _______ extant genera of xiphosurids, whose distribution spans from North America to southern Asia and Japan.

3

Select all of the following that can be components of the arthropod procuticle.

Calcium carbonate Protein Chitin

The extinct eurypterids had which of the following features in common with extant scorpions and horseshoe crabs?

Chelicerae Head with six fused segments

Select all of the characteristics of arthropods.

Chitinous exoskeleton Triploblastic body Excretion by Malpighian tubules

Which of the following accurately describes the arrangement of the longitudinal muscles of nematodes?

Each muscle cell has a contractile fibrillar portion and a noncontractile sarcoplasmic portion. They are arranged in four bands separated by four hypodermal cords.

Arthropods share which of the following common features?

Exoskeleton Jointed appendages Segmented bodies

Arthropods utilize which of the following feeding modes?

Herbivory Carnivory Omnivory

Arthropods are members of subphylum

Hexapoda

Within the subphylum Chelicerata, select all organisms belonging to class Merostomata.

Horseshoe crabs Eurypterids

Select all of the following that are members of the subphylum Chelicerata.

Horseshoe crabs Ticks Sea Spiders

Acarines inhabit which of the following regions?

Hot springs Deserts Forests Polar

The arthropod exoskeleton confers which of the following selective advantages?

It permits moveable joints. It provides a point of attachment for muscles. It provides protection.

Select all of the following that describe the hydrostatic skeleton of nematodes.

It transmits the force of muscle contractions to the cuticle. It contains the internal organs. It is a fluid-filled pseudocoel.

Select all of the characteristics that can be used to distinguish male nematodes from female nematodes.

Males possess a pair of copulatory spicules. Males are smaller than females.

In spiders and other taxa, structures called ____, ____ work in conjunction with rectal glands and function as an excretory organ to remove wastes.

Malpighian tubules

The arrangement of nerve processes in nematodes differs from most animals. Which of the following accurately describes the arrangement of nerve processes in nematodes?

The muscle arm extends to the ventral or dorsal nerve.

Select all true statements about scorpion feeding.

They are nocturnal feeders. They seize prey with their pedipalps.

Which of the following are characteristics of members in Class Arachnida?

They are predatory. They are aquatic. They are terrestrial. They are parasitic

Select all of the following that describe members of Order Acari

They are vectors for disease. They are ectoparasitic. They are free-living scavengers.

Chiggers, belonging to genus Trombicula, are harmful in what ways?

They spread typhus. They can cause dermatitis. They feed on human tissues.

A scorpion mother carries her young on her back until

after their first molt

Funnelweb spiders of the genus Atrax are found in ______ and are considered to be a fatal species.

australia

The stinger of a scorpion is comprised of which of the following?

barb & base

Acarines are characterized by their ______, an anterior projection that contains their mouthparts.

capitulum

The venom of the scorpion belonging to Genus ___ in Mexico can be fatal

centruroides

All species in Class Arachnida have a fused head and thorax called a

cephalothorax

Unlike other arachnids, acarines have a fully fused ____ and _____ .

cephalothorax & abdomen

Horseshoe crabs, scorpions, spiders, and ticks belong to Subphylum

chelicerata

Based on the following cladogram, subphlyum Myriapoda is more closely related to subphylum ______ than to subphylum ______.

crustacea chelicerata

All arthropods have a distinctive, lightweight ____ which is composed of chitin and proteins and provides protection while allowing efficient locomotion.

cuticle

Nematodes are characterized as having a flexible, nonliving _____, the presence of longitudinal _____along their body wall, and no motile cilia or flagella.

cuticle & muscles

Disease

demodex: mange sarcoptes: itching rhipiecephalus: texas cattle ixodes: Lyme disease trombicula: typhus

The most common filarial worm in the United States is the ______, Dirofilaria immitis.

dog heart worm

Arthropods are _______ ________ belonging to clade Panarthropoda.

ecdysozoan protostomes

Repeated exposure to Wuchereria bancrofti infection may cause what diseases?

elephantiasis

Repeated exposure to filarial worms may cause a disease called _____, which is characterized by excessive growth of connective tissues and extensive swelling of affected body parts.

elephantiasis

The outer, sclerotized layer of the arthropod cuticle is called the ______, while the inner layer containing chitin is called the ______.

epicuticle Procuticle

The arthropod cuticle is composed of two layers: the outer, relatively thin layer called the ____ , and an inner, thicker layer called ____ the that contains chitin.

epicuticle & procuticle

Class Merostomata includes the extinct giant water scorpions, which are called.

eurypterids

True or false: Scientists postulate that the tracheae in spiders and insects are homologous and are therefore a product of divergent evolution

false

Place the steps of a pinworm life cycle in order beginning at the top with egg laying

females migrate to the anal region scratching contaminates eggs are swallowed pinworms mature

In Africa, the Mideast, Central America, and South America, what nematode causes onchocerciasis, which is also called river blindness?

filarial worm

Wuchereria bancrofti is one of eight species of ______ that cause diseases in humans.

filarial worms

Arthropods are currently divided into ______ subphyla.

five

Chelicerate arthropods are characterized by a pair of pedipalps, a pair of chelicerae, and ______ pairs of walking legs.

four

The longitudinal muscles of nematodes are arranged in _____ bands, separated by _____ hypodermal cords. Each muscle cell has a contractile ____ portion and a noncontractile _____ portion.

four four fibrillar sarcoplasmic

A scorpion's pectines or tactile organs serve what function(s)?

ground exploration & sex recognition

Most arthropods are _____ feeding mainly on plants.

herbivorous

____ worms are parasitic with multiple hosts during their life cycle. Juveniles that encyst on vegetation may be eaten by a grasshopper.

horsehair

The internal organs of nematodes lie within a fluid-filled pseudocoel that also functions as a _____ skeleton.

hydrostatic

The cuticle of nematodes functions to contain the high _____pressure exerted by fluid in the ______ , and as protection against hostile environmental conditions.

hydrostatic & pseudocoel

A scorpion's stinger consists of a bulbous base and curved barb and is located on the ______ segment of its body.

last

Scorpion tagmata bear two to five pairs of small ____ eyes and one pair of larger _____ eyes.

lateral & median

In spiders, the cephalothorax and abdomen are attached by a narrow, waist-like

pedicel

In spiders, the pair of leglike appendages that have sensory or reproductive functions are

pedipalps

The alimentary canal of nematodes consists of a mouth, a muscular ___, a long nonmuscular ____, a short _____ , and a terminal anus

pharynx intestine rectum

The nervous system of nematodes consists of a ring of nerve tissue and ganglia around the ______. Nerves connect to ______ nerve cords. Multiple choice question.

pharynx & two

A bilateral pair _____ of which of the following is located near the posterior end of parasitic nematodes?

phasmids

The most dangerous and aggressive spiders in South and Central America belong to genus

phoneutria

What is considered to be the most species-rich and diverse phylum in the animal kingdom?

phylum arthropoda

In arthropods, a layer called the ___ is composed of an exocuticle, which is secreted before molting, and a(n) ___ , which is secreted after molting.

pro cuticle & endocuticle

Subphylum Chelicerata consists of Class Arachnida, Class Merostomata, and Class

pycnogonida

In the United States, the black widow spider is characterized by a ______ on the underside of the abdomen, while the brown recluse has a ______ on the cephalothorax.

red hourglass, violin-shaped dorsal stripe

or the cross-linkage of protein in the outer epicuticle, acts to harden and stabilize the arthropod cuticle.

sclerotization

Arthropods can be classified into subgroups based on morphological features of body plans and are divided into ______ based on relationships among these subgroups.

subphyla

Xiphosurids are characterized by their tailpiece, or ____ and tough dorsal shield, known as an ___

telson & carapace

Select all of the following that are included in Order Acari.

ticks & mites

Select all of the parasitic nematodes that are common in humans in North America.

trichina worm pinworm hookworm

Subphylum Trilobita includes arthropods that are now extinct called

trilobites

True or false: Arthropods are members of perhaps the most species-rich and diverse phylum in the animal kingdom.

true

Select all of the characteristics of members of Subphylum Chelicerata.

two tagmata four pairs of walking legs

Scorpions are _______, nourishing their young within the reproductive tract.

viviparous

The colonization of land by spiders and insects is attributable to the retention of ______, made possible by their excretory system.

water & potassium