PCA EXAM- CATEGORY A INSECTS, MITES, AND OTHER INVERTEBRATES ACTUAL
EXAM 2026 | PEST CONTROL ADVISER (PCA) | ALL QUESTIONS AND CORRECT
ANSWERS | VERIFIED ANSWERS | UPDATED VERSION!
Question 1
Which type of insect mouthpart is characterized by mandibles that move laterally to tear, cut, and
grind plant tissue?
A) Haustellate
B) Piercing-sucking
C) Siphoning
D) Chewing (mandibulate)
E) Sponging
Correct Answer: D) Chewing (mandibulate)
Rationale: Mandibulate mouthparts are designed for the physical mastication of solid food.
The mandibles are the primary tools used to mechanically break down plant tissues into
smaller pieces for ingestion.
Question 2
Which of the following insect orders is known for having chewing mouthparts?
A) Hemiptera
B) Thysanoptera
C) Coleoptera
D) Diptera
E) Lepidoptera (adults)
Correct Answer: C) Coleoptera
Rationale: Coleoptera (beetles) possess chewing mouthparts in both their larval and adult
stages. In contrast, orders like Hemiptera have piercing-sucking mouthparts.
Question 3
Which mouthpart type uses needle-like stylets to penetrate plant cells and extract fluids?
A) Siphoning
B) Sponging
C) Rasping-sucking
D) Piercing-sucking
E) Mandibulate
Correct Answer: D) Piercing-sucking
Rationale: Piercing-sucking insects (like aphids or true bugs) do not remove chunks of
tissue. Instead, they use specialized stylets to pierce the epidermis and vascular tissues to
suck up sap or cell contents.
Question 4
Which of the following best describes "Siphoning" mouthparts?
A) Hard jaw-like structures for grinding
B) A coiled proboscis used to feed on nectar
, 2
C) A labellum used to absorb liquid food
D) Rasping tissue then sucking fluids
E) Stylets used to inject toxins
Correct Answer: B) A coiled proboscis used to feed on nectar
Rationale: Siphoning mouthparts are characteristic of adult butterflies and moths
(Lepidoptera), allowing them to reach nectar deep within flowers.
Question 5
"Rasping-sucking" mouthparts are a unique intermediate form primarily found in which group?
A) Mosquitoes
B) Grasshoppers
C) Thrips
D) House flies
E) Weevils
Correct Answer: C) Thrips
Rationale: Thrips (Thysanoptera) use their mouthparts to scrape or "rasp" the surface of
plant tissue before sucking up the exuding fluids, often leading to a silvery or scarred
appearance on leaves.
Question 6
What is a primary diagnostic difference between the damage caused by chewing mouthparts and
piercing-sucking mouthparts?
A) Chewing mouthparts cause wilting only.
B) Piercing-sucking mouthparts create visible holes and defoliation.
C) Chewing mouthparts create visible holes; piercing-sucking mouthparts cause yellowing or
stunting.
D) Chewing mouthparts cause "honeydew" production.
E) There is no visible difference in damage.
Correct Answer: C) Chewing mouthparts create visible holes; piercing-sucking mouthparts
cause yellowing or stunting.
Rationale: Chewing insects physically remove tissue (holes/notches), whereas piercing-
sucking insects cause physiological stress through fluid removal, often resulting in systemic
symptoms like chlorosis or wilting.
Question 7
The body of an adult insect is divided into which three main regions?
A) Cephalothorax, abdomen, legs
B) Head, thorax, abdomen
C) Idiosoma, gnathosoma, thorax
D) Pro, meso, and metathorax
E) Head, cephalothorax, abdomen
, 3
Correct Answer: B) Head, thorax, abdomen
Rationale: This three-part tagmosis is the defining anatomical characteristic of the Class
Insecta.
Question 8
In adult spiders, the body is divided into which two main regions?
A) Head and abdomen
B) Gnathosoma and idiosoma
C) Cephalothorax and abdomen
D) Thorax and abdomen
E) Prosoma and gnathosoma
Correct Answer: C) cephalothorax, abdomen
Rationale: Spiders (Araneae) have the head and thorax fused into a single unit called the
cephalothorax (or prosoma), distinct from the abdomen.
Question 9
Mite anatomy is characterized by which of the following body region divisions?
A) Head, thorax, and abdomen
B) Gnathosoma (head/mouthparts) and idiosoma (fused body)
C) Cephalothorax and abdomen
D) Prothorax and metathorax
E) Fused head and gnathosoma
Correct Answer: B) idiosoma (fused cephalothorax and abdomen), gnathosoma (head and
mouthparts)
Rationale: Mites and ticks (Acari) lack the distinct segmentation seen in insects; their body
parts are largely fused into the gnathosoma and idiosoma.
Question 10
Which sensory organs are located exclusively on the head of an insect?
A) Spiracles
B) Antennae
C) Cerci
D) Prolegs
E) Halteres
Correct Answer: B) antennae
Rationale: The antennae are the primary sensory appendages of the head, used for detecting
chemicals, vibrations, and other environmental cues.
Question 11
Which structure is described as a shield-like plate on the front of the face, located below the
antennae and above the mouthparts?
, 4
A) Labrum
B) Mandible
C) Ocellus
D) Clypeus
E) Maxilla
Correct Answer: D) clypeus
Rationale: The clypeus is a key facial sclerite in insects that helps define the structure of the
head and provides an attachment point for the labrum.
Question 12
In most insects, where are the "ocelli" (simple eyes) typically located?
A) On the abdomen
B) On the sides of the head behind the compound eyes
C) On the front of the head between the compound eyes
D) On the palps
E) On the prothorax
Correct Answer: C) simple eyes that sense light and are located on the front of the head
between the compound eyes
Rationale: Ocelli are simple photoreceptors used primarily for detecting light intensity and
horizon tracking, rather than forming complex images.
Question 13
The segmented sensory appendages found near the mouth and attached to the maxillae and
labium are called:
A) Antennae
B) Stylets
C) Palps
D) Mandibles
E) Ocelli
Correct Answer: C) palps
Rationale: Palps function as "tasters" and "feelers" for the mouthparts, helping the insect
manipulate and evaluate food sources.
Question 14
Which segment of the thorax is responsible for bearing the first pair of legs but NEVER bears
wings?
A) Mesothorax
B) Metathorax
C) Prothorax
D) Endothorax
E) Scutellum
EXAM 2026 | PEST CONTROL ADVISER (PCA) | ALL QUESTIONS AND CORRECT
ANSWERS | VERIFIED ANSWERS | UPDATED VERSION!
Question 1
Which type of insect mouthpart is characterized by mandibles that move laterally to tear, cut, and
grind plant tissue?
A) Haustellate
B) Piercing-sucking
C) Siphoning
D) Chewing (mandibulate)
E) Sponging
Correct Answer: D) Chewing (mandibulate)
Rationale: Mandibulate mouthparts are designed for the physical mastication of solid food.
The mandibles are the primary tools used to mechanically break down plant tissues into
smaller pieces for ingestion.
Question 2
Which of the following insect orders is known for having chewing mouthparts?
A) Hemiptera
B) Thysanoptera
C) Coleoptera
D) Diptera
E) Lepidoptera (adults)
Correct Answer: C) Coleoptera
Rationale: Coleoptera (beetles) possess chewing mouthparts in both their larval and adult
stages. In contrast, orders like Hemiptera have piercing-sucking mouthparts.
Question 3
Which mouthpart type uses needle-like stylets to penetrate plant cells and extract fluids?
A) Siphoning
B) Sponging
C) Rasping-sucking
D) Piercing-sucking
E) Mandibulate
Correct Answer: D) Piercing-sucking
Rationale: Piercing-sucking insects (like aphids or true bugs) do not remove chunks of
tissue. Instead, they use specialized stylets to pierce the epidermis and vascular tissues to
suck up sap or cell contents.
Question 4
Which of the following best describes "Siphoning" mouthparts?
A) Hard jaw-like structures for grinding
B) A coiled proboscis used to feed on nectar
, 2
C) A labellum used to absorb liquid food
D) Rasping tissue then sucking fluids
E) Stylets used to inject toxins
Correct Answer: B) A coiled proboscis used to feed on nectar
Rationale: Siphoning mouthparts are characteristic of adult butterflies and moths
(Lepidoptera), allowing them to reach nectar deep within flowers.
Question 5
"Rasping-sucking" mouthparts are a unique intermediate form primarily found in which group?
A) Mosquitoes
B) Grasshoppers
C) Thrips
D) House flies
E) Weevils
Correct Answer: C) Thrips
Rationale: Thrips (Thysanoptera) use their mouthparts to scrape or "rasp" the surface of
plant tissue before sucking up the exuding fluids, often leading to a silvery or scarred
appearance on leaves.
Question 6
What is a primary diagnostic difference between the damage caused by chewing mouthparts and
piercing-sucking mouthparts?
A) Chewing mouthparts cause wilting only.
B) Piercing-sucking mouthparts create visible holes and defoliation.
C) Chewing mouthparts create visible holes; piercing-sucking mouthparts cause yellowing or
stunting.
D) Chewing mouthparts cause "honeydew" production.
E) There is no visible difference in damage.
Correct Answer: C) Chewing mouthparts create visible holes; piercing-sucking mouthparts
cause yellowing or stunting.
Rationale: Chewing insects physically remove tissue (holes/notches), whereas piercing-
sucking insects cause physiological stress through fluid removal, often resulting in systemic
symptoms like chlorosis or wilting.
Question 7
The body of an adult insect is divided into which three main regions?
A) Cephalothorax, abdomen, legs
B) Head, thorax, abdomen
C) Idiosoma, gnathosoma, thorax
D) Pro, meso, and metathorax
E) Head, cephalothorax, abdomen
, 3
Correct Answer: B) Head, thorax, abdomen
Rationale: This three-part tagmosis is the defining anatomical characteristic of the Class
Insecta.
Question 8
In adult spiders, the body is divided into which two main regions?
A) Head and abdomen
B) Gnathosoma and idiosoma
C) Cephalothorax and abdomen
D) Thorax and abdomen
E) Prosoma and gnathosoma
Correct Answer: C) cephalothorax, abdomen
Rationale: Spiders (Araneae) have the head and thorax fused into a single unit called the
cephalothorax (or prosoma), distinct from the abdomen.
Question 9
Mite anatomy is characterized by which of the following body region divisions?
A) Head, thorax, and abdomen
B) Gnathosoma (head/mouthparts) and idiosoma (fused body)
C) Cephalothorax and abdomen
D) Prothorax and metathorax
E) Fused head and gnathosoma
Correct Answer: B) idiosoma (fused cephalothorax and abdomen), gnathosoma (head and
mouthparts)
Rationale: Mites and ticks (Acari) lack the distinct segmentation seen in insects; their body
parts are largely fused into the gnathosoma and idiosoma.
Question 10
Which sensory organs are located exclusively on the head of an insect?
A) Spiracles
B) Antennae
C) Cerci
D) Prolegs
E) Halteres
Correct Answer: B) antennae
Rationale: The antennae are the primary sensory appendages of the head, used for detecting
chemicals, vibrations, and other environmental cues.
Question 11
Which structure is described as a shield-like plate on the front of the face, located below the
antennae and above the mouthparts?
, 4
A) Labrum
B) Mandible
C) Ocellus
D) Clypeus
E) Maxilla
Correct Answer: D) clypeus
Rationale: The clypeus is a key facial sclerite in insects that helps define the structure of the
head and provides an attachment point for the labrum.
Question 12
In most insects, where are the "ocelli" (simple eyes) typically located?
A) On the abdomen
B) On the sides of the head behind the compound eyes
C) On the front of the head between the compound eyes
D) On the palps
E) On the prothorax
Correct Answer: C) simple eyes that sense light and are located on the front of the head
between the compound eyes
Rationale: Ocelli are simple photoreceptors used primarily for detecting light intensity and
horizon tracking, rather than forming complex images.
Question 13
The segmented sensory appendages found near the mouth and attached to the maxillae and
labium are called:
A) Antennae
B) Stylets
C) Palps
D) Mandibles
E) Ocelli
Correct Answer: C) palps
Rationale: Palps function as "tasters" and "feelers" for the mouthparts, helping the insect
manipulate and evaluate food sources.
Question 14
Which segment of the thorax is responsible for bearing the first pair of legs but NEVER bears
wings?
A) Mesothorax
B) Metathorax
C) Prothorax
D) Endothorax
E) Scutellum
