Part 6 – Population Interactions: Parasitism

Q1.

Parasitism is an interaction in which:
a) Both species benefit
b) One species benefits, the other is harmed
c) Both are harmed
d) Neither benefits

Answer: b) One species benefits, the other is harmed

Explanation:

(a) Mutualism.
(b) Correct → Parasite benefits, host harmed.
(c) Competition.
(d) Neutralism.

Q2.

Which of the following is an ectoparasite?
a) Malarial parasite (Plasmodium)
b) Head louse (Pediculus)
c) Tapeworm
d) Wuchereria

Answer: b) Head louse (Pediculus)

Explanation:

(a) Plasmodium → Endoparasite (blood).
(b) Correct → Lice live on surface.
(c) Tapeworm → Endoparasite (intestine).
(d) Wuchereria → Endoparasite (lymph vessels).

Q3.

Endoparasites are commonly adapted to:
a) Loss of unnecessary organs
b) High reproductive capacity
c) Protective resistant covering
d) All of the above

Answer: d) All of the above

Explanation:
Endoparasites simplify body (no digestion), reproduce fast, develop resistant coatings.

Q4.

Which disease is caused by Plasmodium?
a) Filariasis
b) Malaria
c) Ascariasis
d) Taeniasis

Answer: b) Malaria

Explanation:

(a) Filariasis → Wuchereria.
(b) Correct.
(c) Ascariasis → Ascaris.
(d) Taeniasis → Tapeworm.

Q5.

The intermediate host of malarial parasite is:
a) Human
b) Female Anopheles mosquito
c) Pig
d) Dog

Answer: b) Female Anopheles mosquito

Explanation:

(a) Humans → Definitive host.
(b) Correct → Mosquito carries parasite for transfer.
(c) Not involved.
(d) Not involved.

Q6.

Cuscuta is a parasite that affects:
a) Animals
b) Plants
c) Both
d) Neither

Answer: b) Plants

Explanation:
Cuscuta (dodder plant) is a stem parasite of other plants.

Q7.

Which adaptation is seen in Cuscuta?
a) Chlorophyll presence
b) Haustoria for sucking nutrients
c) Photosynthesis
d) None of the above

Answer: b) Haustoria for sucking nutrients

Explanation:
Cuscuta lacks chlorophyll, uses haustoria to penetrate host plant.

Q8.

Parasitism differs from predation because:
a) Parasite kills host quickly
b) Parasite rarely kills host immediately
c) Both kill their partner
d) Both are neutral

Answer: b) Parasite rarely kills host immediately

Explanation:
Parasite depends on host survival, unlike predators.

Q9.

The parasitic plant that grows on forest trees and absorbs water/minerals only is:
a) Cuscuta
b) Viscum
c) Loranthus
d) Both b and c

Answer: d) Both b and c

Explanation:
Viscum and Loranthus = partial (hemiparasites), photosynthetic but parasitic for water/minerals.

Q10.

Wuchereria bancrofti causes:
a) Malaria
b) Filariasis (elephantiasis)
c) Typhoid
d) Amoebiasis

Answer: b) Filariasis (elephantiasis)

Explanation:

(a) Malaria → Plasmodium.
(b) Correct.
(c) Typhoid → Salmonella typhi.
(d) Amoebiasis → Entamoeba histolytica.

Q11.

In brood parasitism, the parasite:
a) Feeds on host blood
b) Lays eggs in host’s nest
c) Lives inside host’s intestine
d) Attaches externally to host

Answer: b) Lays eggs in host’s nest

Explanation:
E.g., cuckoo lays eggs in crow’s nest, tricking host to raise its chicks.

Q12.

Which of the following shows brood parasitism?
a) Crow
b) Koel (cuckoo)
c) Sparrow
d) Pigeon

Answer: b) Koel (cuckoo)

Explanation:
Cuckoo (koel) lays eggs in crow’s nest → brood parasitism.

Q13.

Brood parasitism benefits parasite by:
a) Extra food
b) No parental care required
c) Killing host directly
d) Producing toxins

Answer: b) No parental care required

Explanation:
Host raises parasite’s young.

Q14.

The parasite causing sleeping sickness is:
a) Plasmodium
b) Trypanosoma
c) Leishmania
d) Entamoeba

Answer: b) Trypanosoma

Explanation:

(a) Malaria.
(b) Correct → Transmitted by tsetse fly.
(c) Kala-azar.
(d) Amoebiasis.

Q15.

Which of the following is an ectoparasite in animals?
a) Tick
b) Tapeworm
c) Ascaris
d) Malarial parasite

Answer: a) Tick

Explanation:
Ticks live on host surface. Others are internal.

Q16.

Why don’t parasites usually kill their host immediately?
a) They are weak
b) They depend on host survival
c) They are non-living
d) They are commensals

Answer: b) They depend on host survival

Explanation:
Killing host = loss of habitat and food.

Q17.

Parasites with complex life cycles often require:
a) Multiple hosts
b) Only one host
c) Free-living stage only
d) No hosts

Answer: a) Multiple hosts

Explanation:
E.g., Plasmodium requires mosquito + human.

Q18.

Which parasite blocks lymphatic vessels?
a) Ascaris
b) Wuchereria
c) Plasmodium
d) Leishmania

Answer: b) Wuchereria

Explanation:
Causes elephantiasis.

Q19.

Which disease is NOT due to parasitism?
a) Kala-azar
b) Filariasis
c) Tuberculosis
d) Malaria

Answer: c) Tuberculosis

Explanation:

(a) Kala-azar → Leishmania.
(b) Filariasis → Wuchereria.
(c) Correct → TB is bacterial infection, not parasite.
(d) Malaria → Plasmodium.

Q20.

Which parasite causes visceral leishmaniasis (kala-azar)?
a) Trypanosoma
b) Leishmania donovani
c) Plasmodium vivax
d) Wuchereria bancrofti

Answer: b) Leishmania donovani

Explanation:
Transmitted by sandfly.

Q21.

Which adaptation is common in parasites?
a) High reproductive rate
b) Special organs of attachment
c) Loss of sensory organs
d) All of the above

Answer: d) All of the above

Explanation:
Parasites evolve to maximize survival inside host.

Q22.

Which is NOT a plant parasite?
a) Cuscuta
b) Viscum
c) Loranthus
d) Rhizobium

Answer: d) Rhizobium

Explanation:
Rhizobium = mutualistic nitrogen fixer, not parasite.

Q23.

Parasites that live inside host body are called:
a) Ectoparasites
b) Endoparasites
c) Hemiparasites
d) Saprophytes

Answer: b) Endoparasites

Explanation:
Examples: Plasmodium, tapeworm.

Q24.

Host-specific parasites are advantageous because:
a) They can infect many hosts
b) They adapt best to one host species
c) They can survive without a host
d) They increase host population

Answer: b) They adapt best to one host species

Explanation:
Specialization increases efficiency of parasitism.

Q25.

Which is NOT a parasitic interaction?
a) Tick on dog
b) Tapeworm in intestine
c) Koel laying eggs in crow’s nest
d) Honeybee on flowers

Answer: d) Honeybee on flowers

Explanation:
Bees and flowers = mutualism, not parasitism.

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Part 6 – Population Interactions: Parasitism