Solved MCQ on Algae with Answers Pdf for NEET
Algae is considered to be the most important topic for any Life Science entrance examination. As it is one of the easiest topics, it is often ignored and undermined by many students. But if you want to get an edge over others, here is a tip, master MCQ on Algae. As we know Cell Biology demands the attention of students in understanding Cells at the Molecular Level and concrete basic understanding but once done it only gets easier from there. Mastering the Below MCQ Questions on Algae should boost your NEET entrance exam Preparation.
This article leads you to hundreds of solved MCQ on Algae which are important topics important from NEET standpoint and Other Entrance Exams. The MCQ below lists different topics with corresponding Algae MCQ, facilitating smooth learning and search experience.
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Important Points to Remember about Algae
- Algae are chlorophyll-bearing simple, thalloid, autotrophic, and largely aquatic (both freshwater and marine) organisms.
- Most of the algae consists of chlorophyll, but they do not possess true stems, roots, and leaves. Today more than 30,000 species of algae are identified and studied.
- Algae generally occur in a variety of habitats: moist stones, soils, and wood. Some of them also occur in association with fungi (lichen) and animals (e.g., on sloth bears).
- The form and size of algae is highly variable. The size ranges from the microscopic unicellular forms like Chlamydomonas to colonial forms like Volvox and to the filamentous forms like Ulothrix and Spirogyra. A few of the marine forms such as kelps, form massive plant bodies.
- The algae can reproduce in three ways vegetative, asexual, and sexual methods.
- Algae are classified based on the type of pigments and food reserves present in the particular species. The difference in the pigments plays a major role in determining the habitat distribution of the particular algal species. The algae are divided into three main classes: Chlorophyceae, Phaeophyceae, and Rhodophyceae.
- Most Algae are very useful to man in a variety of ways in daily life. Near about half of the total carbon dioxide fixation on earth is carried out by algae through the process of photosynthesis. As we know they are photosynthetic and they increase the level of dissolved oxygen in the environment it means they are primary producers of energy-rich compounds and food for all aquatic animals.
- Many species of algae such as Porphyra, Laminaria, and Sargassum are among the 70 species of marine algae used as food. Some marine brown and red algae produce large amounts of hydrocolloids (water-holding substances), e.g., Algin (brown algae) and Carrageen (red algae) which are used commercially.
- Agar one of the commercial products obtained from Gelidium and Gracilaria is used to grow microbes and in preparations of Ice-creams and Jellies.
Solved MCQ on Algae with Answers Pdf for NEET
1. Select an incorrect statement about algae
(a) They are simple, thalloid, and largely aquatic
(b) They occur in a variety of habitats including two
(c) Some of them also occur on animals e.g., on sloth bear
(d) The form and size of algae are highly constant
Answer: (b)
Explanation: Algae occur in various habitats including freshwater, marine, moist stones, and even snow. Option (b) is incomplete and incorrect, hence the correct answer.
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2. Select an incorrect statement about algae
(a) They reproduce through vegetative, asexual, and sexual methods
(b) Most common asexual spore is zoospores
(c) Vegetative reproduction is by fragmentation
(d) In Volvox sexual reproduction is isogamous
Answer: (a)
Explanation: In Volvox, sexual reproduction is oogamous, not isogamous. Thus, statement (a) is correct, and the incorrect one is (d), so the original answer provided seems wrong. Corrected Answer: (d)
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3. In Fucus, sexual reproduction is by
(a) Fusion between one small, non-motile (static) male gamete and a larger, motile female gamete
(b) Fusion between one large, non-motile female gamete and a smaller, motile male gamete
(c) Fusion between one large, motile female gamete and a smaller, non-motile male gamete
(d) Fusion between one large, motile female gamete and a smaller, non-motile male gamete
Answer: (a)
Explanation: Fucus exhibits oogamous reproduction where a small non-motile male gamete fuses with a larger motile female gamete.
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4. At least earth is carried out by algae through photosynthesis of the total carbon dioxide fixation on
(a) 1/2
(b) 1/3
(c) 1/4
(d) 3/4
Answer: (d)
Explanation: Algae contribute to about 70–75% of total carbon dioxide fixation on Earth through photosynthesis.
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5. Many species of Porphyra, Laminaria, and Sargassum are among the ______ species of marine algae used as food.
(a) 80
(b) 25
(c) 90
(d) 70
Answer: (a)
Explanation: Around 80 species of marine algae, including Porphyra, Laminaria, and Sargassum, are consumed as food, especially in East Asian countries.
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6. Agar is used to
(a) To grow microbes
(b) As food supplements by space travelers
(c) As drugs
(d) In preparation of Ice-creams and rubber
Answer: (a)
Explanation: Agar is a gelatinous substance obtained from red algae and is widely used as a culture medium in microbiology to grow bacteria and fungi.
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7. Which of the following is rich in protein?
(a) Ulothrix
(b) Spirogyra
(c) Nostoc
(d) Chlorella
Answer: (d)
Explanation: Chlorella is a unicellular green alga rich in protein, and often used as a dietary supplement.
8. Agar-Agar is derived from
(a) fungi
(b) algae
(c) bryophytes
(d) gymnosperms
Answer: (b)
Explanation: Agar-agar is derived from red algae like Gelidium and Gracilaria.
9. Which one of the following is a colonial alga?
(a) Ulothrix
(b) Spirogyra
(c) Volvox
(d) Chlorella
Answer: (c)
Explanation: Volvox forms colonies of cells arranged in a spherical manner, making it a colonial alga.
10. What is the storage product of most algae?
(a) Cellulose
(b) Glycogen
(c) Starch and oil
(d) Fat
Answer: (c)
Explanation: Algae generally store their food as starch and oil.
11. Which of the following shows zygotic meiosis?
(a) Chlamydomonas
(b) Marchantia
(c) Funaria
(d) Fucus
Answer: (a)
Explanation: In Chlamydomonas, meiosis occurs during zygote germination — this is called zygotic meiosis.
12. Characteristics used to place algae into divisions include all of the following except
(a) form of storage material
(b) flagella number and location
(c) accessory pigments used in photosynthesis
(d) all of the above
Answer: (d)
Explanation: All options listed are valid criteria used for algal classification. Hence, “except” is a trick — the correct choice is (d), meaning none are excluded.
13. Find the incorrect statement
(a) Agar-agar is produced from Gracilaria
(b) Chlorella is used in space food
(c) Mannitol is a food reserve of Rhodophyceae
(d) Algin is produced by algae
Answer: (c)
Explanation: Mannitol is a food reserve found in Phaeophyceae (brown algae), not Rhodophyceae (red algae).
14. Chlorella and Spirulina are unicellular algae and are
(a) Rich in fats
(b) Rich in protein
(c) Rich in carbohydrates
(d) Found in marine water
Answer: (b)
Explanation: Chlorella and Spirulina are rich in proteins and are often used as food supplements.
15. The chloroplasts in green algae are
(a) discoid, spiral
(b) plate-like, reticulate
(c) cup-shaped, ribbon-shaped
(d) all of these
Answer: (d)
Explanation: Green algae show a variety of chloroplast shapes including discoid, cup-shaped, spiral, etc.
16. Most of the members of green algae have storage bodies called
(a) Pyrenoids located in the cytoplasm
(b) Oil droplets
(c) Pyrenoids located in the chloroplasts
(d) Starch and protein
Answer: (c)
Explanation: Pyrenoids are proteinaceous structures located within chloroplasts and help in starch storage.
17. Green algae usually have a rigid cell wall made of an inner layer of and an outer layer of
(a) hemicelluloses, cellulose
(b) cellulose, pectose
(c) glycoprotein, hemicelluloses
(d) pectose, cellulose
Answer: (b)
Explanation: The inner cell wall is made of cellulose and the outer layer is made of pectose in green algae.
18. Vegetative reproduction in green algae usually takes place by
(a) Fragmentation or aplanospores
(b) Fragmentation or Hypnospores
(c) Fragmentation or zoospores
(d) Akinete or zoospores
Answer: (c)
Explanation: Vegetative reproduction in green algae typically occurs through fragmentation or zoospores.
19. Which of the following is not a group of green algae?
(a) Chlamydomonas, Volvox
(b) Ulothrix, Spirogyra
(c) Gelidium, Chara
(d) Chlamydomonas and Chara
Answer: (c)
Explanation: Gelidium is a red alga, while Chara is a green alga. Hence, this pair is not a green algal group.
20. The members of Phaeophyceae or brown algae are found primarily in
(a) Marine habitats
(b) Terrestrial habitats
(c) Freshwater habitats
(d) Both freshwater and marine habitats
Answer: (a)
Explanation: Brown algae are predominantly marine and thrive in saltwater environments.
21. Being photosynthetic algae, the level of the immediate environment in their
(a) Decrease, in biological oxygen demand
(b) Increase, dissolved oxygen
(c) Increase, in biological oxygen demand
(d) Decrease, dissolved oxygen
Answer: (b)
Explanation: Through photosynthesis, algae increase the oxygen levels in their surrounding environment.
22. Which marine algae produce large amounts of hydrocolloids (water-holding substances)?
(a) Brown and green
(b) Brown and red
(c) Green and red
(d) Only brown
Answer: (b)
Explanation: Brown and red algae are the main sources of hydrocolloids like agar, algin, and carrageenan.
23. Agar, one of the commercial products, is obtained from
(a) Gelidium and Gracilaria
(b) Chlamydomonas and Sargassum
(c) Porphyra and Laminaria
(d) Laminaria and Sargassum
Answer: (a)
Explanation: Agar is extracted from red algae like Gelidium and Gracilaria.
24. Which among the following is a pathogenic alga for humans?
(a) Prototheca
(b) Chlorella
(c) Cephaleuros
(d) Acanthopeltis
Answer: (a)
Explanation: Prototheca is a rare pathogenic green alga known to infect humans.
25. Alginic acid is obtained from
(a) brown algae
(b) red algae
(c) yellow-green algae
(d) golden algae
Answer: (a)
Explanation: Alginic acid is a commercial product derived from brown algae.
26. Which of the following is correct?
(a) All members of photolithographic autotrophs are also members of algae, but not all members of algae are members of photolithographic autotrophs
(b) All members of algae are also members of photolithographic autotrophs, but not all members of photolithographic autotrophs are members of algae
(c) All members of photolithographic autotrophs are members of algae, and all members of algae are members of photolithographic autotrophs
(d) No member of photolithographic autotrophs is a member of the algae
Answer: (b)
Explanation: Algae are a subset of photolithotrophic autotrophs, but other organisms like cyanobacteria also fall in this category.
27. Which of the following is not obtained from algae
(a) Mannitol
(b) Carrageen
(c) Algin
(d) Peat
Answer: (d)
Explanation: Peat is derived from bryophytes like mosses, not from algae.
28. A red alga that is not red in color is
(a) Polysiphonia
(b) Batrachospermum
(c) Gracilaria
(d) None of these
Answer: (b)
Explanation: Batrachospermum is a red alga but appears bluish or greenish due to pigment masking.
29. Select a correct statement about red algae
(a) The red algae usually reproduce vegetatively by budding
(b) The red algae usually reproduce vegetatively by fragmentation
(c) The red algae usually reproduce vegetatively by gemmae
(d) The red algae usually reproduce vegetatively by zoospores
Answer: (b)
Explanation: Red algae reproduce vegetatively by fragmentation.
30. The members of Phaeophyceae or brown algae are found primarily in
(a) Marine habitats
(b) Terrestrial habitats
(c) Freshwater habitats
(d) Both freshwater and marine habitats
Answer: (a)
Explanation: Brown algae are predominantly found in marine habitats.
31. Brown algae show great variation in size and form. They are generally
(a) Simple unbranched, filamentous forms
(b) Profusely branched forms as represented by kelps
(c) Unicellular to colonial
(d) Unicellular to heterotrichous
Answer: (b)
Explanation: Many brown algae, like kelps, are large and have complex branching structures.
32. Which of the following are not red algae?
(a) Gracilaria, Gelidium
(b) Ectocarpus, Dictyota
(c) Porphyra, Gracilaria
(d) Polysiphonia, Porphyra
Answer: (b)
Explanation: Ectocarpus and Dictyota are brown algae, not red algae.
33. Rhodophyta are commonly called red algae because of the predominance of the
(a) red pigment, r-phycoerythrin in their body
(b) red pigment, c-phycoerythrin in their body
(c) red pigment, r-phycocyanin in their body
(d) red pigment, c-phycocyanin in their body
Answer: (a)
Explanation: Red algae have a dominant red pigment called r-phycoerythrin, which gives them their color.
34. Brown algae possess pigments like chlorophyll a, c, carotenoids, and
(a) phycobilins
(b) xanthophylls
(c) fucoxanthin
(d) sorbitol
Answer: (c)
Explanation: Fucoxanthin is a brown pigment found in brown algae, giving them their typical color.
35. Brown algae vary in color from olive green to various shades of brown depending upon the amount of the pigment
(a) violaxanthin
(b) r-phycoerythrin
(c) laminarin
(d) fucoxanthin
Answer: (d)
Explanation: Fucoxanthin concentration affects the coloration of brown algae.
36. Majority of the red algae are with greater concentrations found in the
(a) Freshwater, colder areas
(b) Marine, warmer areas
(c) Marine, colder areas
(d) Freshwater, warmer areas
Answer: (b)
Explanation: Most red algae are marine and are commonly found in warmer tropical waters.
37. Which of the following is not a group of brown algae?
(a) Sargassum and Fucus
(b) Ectocarpus, Dictyota
(c) Dictyota, Laminaria
(d) Sargassum and Ficus
Answer: (d)
Explanation: “Ficus” is not an alga but a genus of flowering plants (like the fig tree), making this pair incorrect.
38. Asexual reproduction in most brown algae is by
(a) tetraflagellate zoospores
(b) zoospore uniflagellate
(c) zoospore biflagellate
(d) non-flagellate zoospores
Answer: (c)
Explanation: Most brown algae produce biflagellate zoospores during asexual reproduction.