Exercise Chapter 7 : Protists and Fungi Class 11

MCQs with answers from Chapter 7 : Protists and Fungi (Federal Board, 11th Class):

MCQs – Protists and Fungi

Here are the correct answers with explanations:

Which of the following is true of both fungi and some types of bacteria?
- A) They both produce gametes ❌ (Only fungi produce gametes, not bacteria.)
- B) They both engulf microscopic animals ❌ (Neither fungi nor bacteria engulf food; they absorb nutrients.)
- C) They both absorb materials across the cell wall ✅ (Both fungi and some bacteria absorb nutrients via their cell walls.)
- D) They both fix nitrogen ❌ (Only certain bacteria, like Rhizobium, fix nitrogen, not fungi.)
The cell wall consists of two overlapping shells in:
- A) Euglenoids ❌ (Euglenoids lack a cell wall; they have a pellicle.)
- B) Diatoms ✅ (Diatoms have a silica cell wall with two overlapping halves.)
- C) Dinoflagellates ❌ (Dinoflagellates have cellulose plates, not overlapping silica shells.)
- D) Brown algae ❌ (Brown algae have cellulose and alginic acid in their walls, not overlapping shells.)
Which of the following structures would you expect to find in the corn smut fungus?
- A) Zoospores ❌ (Corn smut fungus does not produce motile zoospores.)
- B) Basidiospores ✅ (Corn smut, a basidiomycete, produces basidiospores.)
- C) Ascospores ❌ (Ascospores are found in ascomycetes, not basidiomycetes.)
- D) Zygospores ❌ (Zygospores are found in zygomycetes, not basidiomycetes.)
The feeding stage of a slime mold is called:
- A) Hyphae ❌ (Hyphae are found in fungi, not slime molds.)
- B) Plasmodium ✅ (Slime molds form a multinucleated, amoeboid plasmodium during feeding.)
- C) Rhizoids ❌ (Rhizoids help in attachment, not feeding.)
- D) Mycelium ❌ (Mycelium is a fungal structure, not a slime mold stage.)
Which is found in slime molds but not in fungi?
- A) Non-motile spores ❌ (Both fungi and slime molds can have non-motile spores.)
- B) Amoeboid adult ✅ (Slime molds have an amoeboid, crawling plasmodial stage, unlike fungi.)
- C) Zygote formation ❌ (Both fungi and slime molds form zygotes.)
- D) Photosynthesis ❌ (Neither fungi nor slime molds photosynthesize.)
Fungi resemble animals because they are:
- A) Saprotrophs ❌ (Not all animals are saprotrophs; fungi are decomposers.)
- B) Autotrophs ❌ (Fungi do not produce their own food.)
- C) Heterotrophs ✅ (Fungi and animals both obtain nutrients from other organisms.)
- D) Heterosporous ❌ (Heterospory is a plant trait, not a fungal one.)
Fungal cell walls contain chitin, which is also found in the exoskeleton of:
- A) Arthropods ✅ (Arthropod exoskeletons and fungal cell walls both contain chitin.)
- B) Molluscs ❌ (Molluscs have calcium carbonate shells, not chitin.)
- C) Echinoderms ❌ (Echinoderms have calcium carbonate endoskeletons.)
- D) Chordates ❌ (Chordates have collagen-based structures, not chitin.)
Poisonous mushrooms are called:
- A) Toadstools ✅ (Toadstools are toxic mushrooms.)
- B) Morels ❌ (Morels are edible mushrooms.)
- C) Truffles ❌ (Truffles are edible fungi.)
- D) Tuber ❌ (Tuber is a storage organ in plants, not a poisonous mushroom.)
Which of the following is associated with asexual reproduction in fungi?
- A) Zygospores ❌ (Zygospores form during sexual reproduction in zygomycetes.)
- B) Ascospores ❌ (Ascospores are formed sexually in ascomycetes.)
- C) Basidiospores ❌ (Basidiospores are sexual spores of basidiomycetes.)
- D) Conidia ✅ (Conidia are asexual spores formed by mitosis in fungi.)
Imperfect fungi are called "imperfect" because:

A) They have no zygospores ❌ (Zygospores are absent in some, but this is not why they are called imperfect.)
B) They cause diseases ❌ (Some imperfect fungi are pathogenic, but not all.)
C) They form conidiospores ❌ (Many fungi form conidiospores, not just imperfect fungi.)
D) Sexual reproduction has not been observed ✅ (Imperfect fungi are classified as such because their sexual phase is unknown.)

SECTION 11: SHORT QUESTIONS

Name the three eukaryotic kingdoms.
- Kingdom Plantae, Kingdom Animalia, Kingdom Fungi
How do ciliates differ from other protozoans?
- Ciliates have cilia for movement and feeding, whereas other protozoans may use flagella, pseudopodia, or be non-motile.
- They have two types of nuclei: macronucleus (controls daily activities) and micronucleus (involved in reproduction).
How do algae differ from plants?
- Algae lack true roots, stems, and leaves (plants have differentiated organs).
- Algae can be unicellular, colonial, or multicellular, whereas plants are always multicellular.
What are diatoms?
- Diatoms are unicellular algae with silica cell walls (frustules) that have two overlapping halves.
- They are major contributors to marine and freshwater phytoplankton.
Write two characteristics of:

(a) Protozoa:
- Unicellular, eukaryotic organisms.
- Can be motile using cilia, flagella, or pseudopodia.
(b) Dinoflagellates:
- Have two flagella for movement.
- Some species cause red tides due to toxin production.
(c) Diatoms:
- Have silica-based cell walls (frustules).
- Major photosynthetic organisms in aquatic ecosystems.
(d) Slime molds:
- Have an amoeboid (plasmodial) feeding stage.
- Exhibit spore formation like fungi.
(e) Oomycetes (water molds):
- Have cell walls made of cellulose (unlike fungi, which have chitin).
- Reproduce sexually via oogonia and antheridia.
How do fungi resemble plants?
- Both have cell walls (fungi → chitin, plants → cellulose).
- Both are non-motile and grow anchored in one place.
Define coenocytic hyphae.
- Hyphae that lack septa (cross walls), forming a continuous multinucleated cytoplasmic mass (e.g., Rhizopus).
How do fungi get their nutrition?
- Fungi are heterotrophic and obtain nutrients by absorbing organic matter through extracellular digestion.
- They can be saprophytic, parasitic, or mutualistic.
Name the fungal mutualistic associations.
- Lichens (fungus + algae/cyanobacteria).
- Mycorrhizae (fungus + plant roots).
List the methods of asexual reproduction in fungi.

Budding (e.g., Yeast).
Binary fission.
Fragmentation.
Sporulation (formation of asexual spores like conidia, sporangiospores).

11. What is a zygospore, and how is it formed?

A zygospore is a thick-walled, resistant sexual spore formed in Zygomycota (e.g., Rhizopus).
It is formed by the fusion of two opposite mating hyphae (gametangia), leading to a diploid zygote, which undergoes meiosis upon germination.

12. Where are basidiospores produced?

Basidiospores are produced on the basidium, a club-shaped structure found on the gills or pores of Basidiomycota fungi (e.g., mushrooms, rusts, and smuts).

13. What do you mean by imperfect fungi? Why are they given this name?

Imperfect fungi (Deuteromycota) are those in which the sexual stage of reproduction is unknown.
They are called "imperfect" because only asexual reproduction (conidia formation) has been observed.

14. What is histoplasmosis?

A fungal respiratory disease caused by Histoplasma capsulatum.
It is transmitted via inhalation of spores from bird/bat droppings in soil.

15. Write one difference between:

Feature	Difference
(a) Fungi vs. Plants	Fungi are heterotrophic, plants are autotrophic.
(b) Fungi vs. Animals	Fungi have cell walls (chitin), animals lack cell walls.
(c) Zygomycota vs. Basidiomycota	Zygomycota reproduce via zygospores, Basidiomycota via basidiospores.
(d) Sporangium vs. Conidium	Sporangium produces spores inside a sac, conidia are borne freely on conidiophores.
(e) Ascus vs. Basidium	Ascus produces ascospores (Ascomycota), basidium produces basidiospores (Basidiomycota).
(f) Dikaryotic vs. Diploid	Dikaryotic cells have two distinct nuclei (n + n), diploid cells have a single nucleus (2n).
(g) Ascocarp vs. Ascus vs. Ascospores	Ascocarp is the fruiting body, ascus is the sac-like structure, ascospores are spores inside the ascus.
(h) Basidiocarp vs. Basidium vs. Basidiospores	Basidiocarp is the fruiting body, basidium is the spore-producing structure, basidiospores are spores formed on basidium.
(i) Endomycorrhizae vs. Ectomycorrhizae	Endomycorrhizae penetrate inside root cells, ectomycorrhizae form a sheath around roots.

16. List some fungi that attack crops. In what division is each found?

Crop Disease	Causative Fungus	Division
Late blight of potato	Phytophthora infestans	Oomycota
Rust disease	Puccinia spp.	Basidiomycota
Ergot disease of rye	Claviceps purpurea	Ascomycota
Corn smut	Ustilago maydis	Basidiomycota
Rice blast	Magnaporthe oryzae	Ascomycota

17. List the differences between bacteria and fungi.

Feature	Bacteria	Fungi
Cell Type	Prokaryotic	Eukaryotic
Cell Wall	Peptidoglycan	Chitin
Mode of Nutrition	Autotrophic or Heterotrophic	Heterotrophic
Reproduction	Binary fission	Asexual & Sexual
Nucleus	Absent	Present

18. Why are fungi and plants classified in different kingdoms?

Fungi lack chlorophyll and cannot perform photosynthesis, unlike plants.
Fungal cell walls contain chitin, while plant cell walls contain cellulose.
Fungi obtain nutrients by absorption, while plants make their own food.

19. What ecological consequences would occur if all fungi on Earth were destroyed by humans using a deadly fungicide?

No decomposition: Dead organic matter would accumulate, disrupting the nutrient cycle.
No mycorrhizal associations: Many plants depend on fungi for nutrient absorption.
Increased plant diseases: Fungi compete with pathogenic microbes; their absence would allow harmful pathogens to thrive.
Loss of food sources: Many fungi are used in food production (e.g., mushrooms, bread, cheese, alcohol fermentation).
No antibiotics or industrial enzymes: Fungi produce important antibiotics (e.g., penicillin) and enzymes used in biotechnology.

SECTION III: EXTENSIVE QUESTIONS

1. Important Features of Protists

Eukaryotic: Possess a true nucleus and membrane-bound organelles.
Mostly unicellular: Some are colonial or multicellular (e.g., kelp).
Varied nutrition: Autotrophic (algae), heterotrophic (protozoa), or mixotrophic (euglenoids).
Locomotion: Use cilia (Paramecium), flagella (Euglena), or pseudopodia (Amoeba) for movement.
Reproduction: Asexual (binary fission, budding) or sexual (conjugation, gamete fusion).
Diverse habitats: Found in aquatic, moist terrestrial, or parasitic environments.

2. Reasons for a Separate Kingdom Protista

Protists do not fit into plants, animals, or fungi due to unique characteristics.
Some are photosynthetic (algae) but lack true roots, stems, and leaves like plants.
Some are heterotrophic (protozoa) but lack complex tissues like animals.
Cell wall composition varies: Some have cellulose, some silica (diatoms), and some lack walls.
Evolutionarily, they are precursors to multicellular life.

3. Importance of Protists

Ecological Role:
- Phytoplankton (e.g., diatoms) produce oxygen via photosynthesis.
- Decomposers recycle nutrients.
Food Chain:
- Protists serve as primary producers in aquatic ecosystems.
Economic Uses:
- Red algae (Gelidium) used in agar production.
- Brown algae (Laminaria) used in food and cosmetics.
Medical Importance:
- Some cause diseases (e.g., Plasmodium → malaria, Entamoeba histolytica → dysentery).
Symbiotic Relationships:
- Termites rely on flagellated protists to digest wood.

4. General Characteristics of Algae

Eukaryotic, autotrophic, photosynthetic organisms.
Diverse body forms: Unicellular (Chlamydomonas), filamentous (Spirogyra), colonial (Volvox), multicellular (Kelp).
Habitat: Found in freshwater, marine, and moist terrestrial environments.
Pigmentation varies:
- Green algae → Chlorophyll a & b (e.g., Chlamydomonas).
- Brown algae → Fucoxanthin (e.g., Laminaria).
- Red algae → Phycoerythrin (e.g., Polysiphonia).
Reproduction:
- Asexual: Binary fission, fragmentation, spore formation.
- Sexual: Isogamy, anisogamy, oogamy.

5. Structure and Reproduction of Slime Molds

Structure:
- Exist as plasmodium (multinucleated, amoeboid mass) in feeding stage.
- During harsh conditions, they form sporangia, which release spores.
Reproduction:
- Asexual: Spores germinate into amoeboid cells.
- Sexual: Fusion of two gametes → zygote → plasmodium formation.

6. Features that Distinguish Oomycotes (Water Molds) from Fungi

Feature	Oomycetes	Fungi
Cell wall	Cellulose	Chitin
Hyphae	Aseptate	Septate or aseptate
Nutrition	Absorptive heterotrophs	Absorptive heterotrophs
Reproduction	Zoospores (asexual), Oogonia + antheridia (sexual)	Various spores (asexual & sexual)
Example	Phytophthora infestans	Rhizopus, Aspergillus

7. Important Features of Basidiomycota

Club fungi (e.g., mushrooms, smuts, rusts).
Reproduce sexually via basidiospores, produced on basidia.
Dikaryotic phase dominant.
Mycelium forms fruiting body (basidiocarp), e.g., mushroom cap.
Examples: Agaricus bisporus (mushroom), Puccinia (rust fungus).

8. General Characteristics of Fungi

Eukaryotic, heterotrophic organisms.
Cell wall contains chitin.
Unicellular (yeast) or multicellular (molds, mushrooms).
Body consists of hyphae, forming mycelium.
Reproduction:
- Asexual → Budding, fragmentation, conidia, sporangiospores.
- Sexual → Ascospores, basidiospores, zygospores.
Modes of Nutrition:
- Saprophytic (decomposers), parasitic, mutualistic.

9. Taxonomic Status of Fungi

Initially classified as plants due to non-motile nature.
Now placed in Kingdom Fungi due to heterotrophic nature, chitinous cell walls, and unique reproduction.
Major phyla:
- Zygomycota (zygospores).
- Ascomycota (ascospores).
- Basidiomycota (basidiospores).
- Chytridiomycota (motile zoospores).

10. Major Divisions of Fungi, Their Features, and Examples

Division	Feature	Example
Zygomycota	Aseptate hyphae, forms zygospores	Rhizopus stolonifer (bread mold)
Ascomycota	Sac fungi, forms ascospores in asci	Saccharomyces cerevisiae (yeast)
Basidiomycota	Club fungi, forms basidiospores on basidia	Agaricus bisporus (mushroom)
Chytridiomycota	Forms zoospores (motile spores)	Batrachochytrium dendrobatidis (amphibian pathogen)
Deuteromycota (Imperfect Fungi)	No observed sexual reproduction	Penicillium (antibiotic producer)

11. Beneficial and Harmful Fungi

Beneficial Fungi

Food Industry:
- Saccharomyces cerevisiae (yeast) → Used in baking & alcohol fermentation.
- Aspergillus oryzae → Used in soy sauce production.
Medicine:
- Penicillium → Source of penicillin (antibiotic).
- Tolypocladium → Produces cyclosporine (immunosuppressant).
Agriculture:
- Mycorrhizae (Glomus spp.) → Enhance plant nutrient absorption.
- Biopesticides (Beauveria bassiana) → Control insect pests.
Decomposition:
- Saprophytic fungi break down dead organic matter, recycling nutrients.
Food Source:
- Edible mushrooms (Agaricus bisporus), truffles, morels are consumed globally.

Harmful Fungi

Plant Pathogens:
- Puccinia graminis → Causes wheat rust.
- Phytophthora infestans → Causes potato late blight.
Human Pathogens:
- Candida albicans → Causes candidiasis (yeast infections).
- Histoplasma capsulatum → Causes histoplasmosis (lung infection).
- Aspergillus fumigatus → Causes aspergillosis in immunocompromised patients.
Mycotoxins:
- Aspergillus flavus → Produces aflatoxins, leading to liver cancer.
- Claviceps purpurea → Produces ergot alkaloids, causing ergotism.
Food Spoilage:
- Rhizopus stolonifer (bread mold) → Spoils food.
- Penicillium → Spoils citrus fruits.

12. Pathogenic Role of Fungi

Fungi can cause diseases in humans, animals, and plants.

1. Human Fungal Infections (Mycoses)

Superficial Mycoses:
- Malassezia furfur → Tinea versicolor (skin infection).
Cutaneous Mycoses:
- Trichophyton, Microsporum → Ringworm, athlete’s foot.
Subcutaneous Mycoses:
- Sporothrix schenckii → Sporotrichosis (Rose gardener’s disease).
Systemic Mycoses:
- Histoplasma capsulatum → Histoplasmosis.
- Coccidioides immitis → Valley fever.
Opportunistic Mycoses:
- Candida albicans → Oral & genital candidiasis.
- Cryptococcus neoformans → Cryptococcal meningitis (AIDS patients).

2. Plant Fungal Infections

Puccinia (Rust fungi) → Causes wheat rust.
Magnaporthe oryzae → Causes rice blast disease.
Ustilago maydis → Causes corn smut.

3. Animal Fungal Infections

Microsporum spp. → Ringworm in cattle.
Batrachochytrium dendrobatidis → Causes chytridiomycosis in amphibians.

13. Club Fungi & Life Cycle of a Mushroom

Definition of Club Fungi

Club fungi belong to Basidiomycota.
They produce basidiospores on club-shaped basidia.
Examples: Mushrooms (Agaricus), Rusts (Puccinia), Smuts (Ustilago).

**Life Cycle of a Mushroom (Agaricus bisporus)**

1. Spore Germination

Haploid basidiospores (n) germinate → form monokaryotic hyphae.

2. Plasmogamy (Fusion of Cytoplasm)

Two compatible monokaryotic hyphae fuse, forming dikaryotic mycelium (n + n).

3. Mycelial Growth

Dikaryotic mycelium spreads underground → forms basidiocarp (fruiting body/mushroom).

4. Karyogamy (Fusion of Nuclei)

Inside basidium (club-shaped structure on gills), two nuclei fuse → diploid nucleus (2n).

5. Meiosis

The diploid nucleus undergoes meiosis, producing haploid basidiospores (n).

6. Spore Dispersal

Basidiospores are released, dispersed by wind, and germinate to restart the cycle.

Exercise | Chapter 7 : Protists and Fungi | Class 11 Biology Notes (FBISE, Best for Exams)