Which one of the following is not a characteristic feature of fungi?
- (a)Cell wall is made of chitin
- (b)Filamentous mycelium is present
- (c)Can carry out photosynthesis
- (d)Asexual spores are produced
Correct — C, Can carry out photosynthesis. Fungi lack chlorophyll and chloroplasts, so they cannot photosynthesise; they are heterotrophs that absorb nutrients from organic matter, living as saprophytes or parasites. The other three options are genuine features of fungi, so 'can carry out photosynthesis' is the one that is NOT characteristic of them.
- (a)Cell wall is made of chitin — Fungal cell walls are indeed made largely of chitin, so this is a true feature of fungi and not the exception.
- (b)Filamentous mycelium is present — Most fungi do have a body of thread-like hyphae forming a mycelium, a genuine fungal characteristic.
- (d)Asexual spores are produced — Fungi commonly reproduce by asexual spores such as conidia and sporangiospores, so this too is a true feature.
Fungi form their own kingdom of eukaryotes that are heterotrophic and absorptive in nutrition. Their body is usually a mycelium of hyphae, their walls contain chitin, and they reproduce by spores. Crucially they have no chlorophyll, so unlike plants they cannot make food by photosynthesis.
The item asks for the odd one out. Three options list well-known fungal traits (chitin walls, mycelium, spores); the exception is photosynthesis, which needs chlorophyll that fungi simply do not possess.
- Fungi are heterotrophic — they have no chlorophyll and cannot photosynthesise.
- Fungal cell walls contain chitin, unlike the cellulose walls of plants.
- The fungal body is typically a mycelium made of hyphae.
- Fungi store food as glycogen, as animals do, rather than as starch.
- Assuming fungi are plants that photosynthesise.
- Forgetting that fungal walls are chitin, not cellulose.
NDA/UPSC ask which trait is or is not a fungal feature — remember fungi are heterotrophic (no chlorophyll), with chitin walls, mycelium and spores.
With reference to the food chains in ecosystems, which of the following kinds of organism is/are known as decomposer organism/organisms? 1. Virus 2. Fungi 3. Bacteria. Select the correct answer using the codes given below.
- (a) 1 only
- (b) 2 and 3 only
- (c) 1 and 3 only
- (d) 1, 2 and 3
Answer(b) 2 and 3 only — fungi and bacteria are the chief saprophytic decomposers, while viruses are obligate parasites and do not decompose organic matter.
UPSC prelims 2013 identified fungi (with bacteria) as decomposers — a direct consequence of fungi being heterotrophs that absorb organic matter rather than photosynthesise, which is exactly why 'can carry out photosynthesis' is not a fungal feature.
- practice — not a real PYQ
The cell wall of fungi is chiefly composed of
- (a)cellulose
- (b)chitin
- (c)peptidoglycan
- (d)lignin
Answer(b) chitin — fungal walls are made mainly of chitin, unlike the cellulose walls of plants.
- practice — not a real PYQ
Fungi obtain their nutrition mainly by
- (a)photosynthesis
- (b)chemosynthesis
- (c)absorption of organic matter
- (d)ingestion of solid food
Answer(c) absorption of organic matter — fungi are heterotrophs that absorb nutrients as saprophytes or parasites.