Biology · Biological Classification · NEET
It is ASEPTATE. This is the single most tested fact. Phycomycetes hyphae have NO cross-walls (no septa), so the whole hypha is one long tube full of many nuclei sharing common cytoplasm. This condition is called coenocytic. Only Phycomycetes (among the four fungal classes) are aseptate/coenocytic; Ascomycetes, Basidiomycetes and Deuteromycetes all have septate mycelium. For NEET: if a question mentions coenocytic or aseptate fungus, the answer is Phycomycetes (Rhizopus/Mucor/Albugo).
They are called algal fungi because their aseptate, coenocytic body looks like some algae (like Vaucheria), and because they produce motile zoospores with flagella, just like many algae do. They are called lower fungi because they are the simplest and most primitive class. NCERT and NEET both accept 'Phycomycetes = algal fungi' as a correct statement (this exact wording was tested in NEET 2016).
Both are asexual spores made INSIDE a sporangium (endogenously) in Phycomycetes. A ZOOSPORE is motile — it has flagella and can swim, so it is common in aquatic species. An APLANOSPORE is non-motile — no flagella, it just gets dispersed. Easy memory: 'Zoo' = animals that move = motile zoospore; 'A' in Aplanospore means 'without' movement. Both are asexual; do NOT confuse them with the sexual zygospore.
A zygospore is the SEXUAL resting spore. Two gametes fuse to form it. These gametes can be similar in shape (isogamous), or dissimilar (anisogamous), or one large non-motile female and one small motile male (oogamous). The thick-walled zygospore survives bad conditions, then later undergoes meiosis and germinates. Key NEET point: zoospore/aplanospore = asexual, zygospore = sexual. Because Rhizopus and Mucor form zygospores, Phycomycetes are also placed in the informal group 'Zygomycetes'.
Yes — these are the three NCERT examples you must memorise. Rhizopus is the common bread mould (grows on stale bread). Mucor is another common mould found on decaying matter and dung. Albugo is a PARASITE that causes white rust disease on mustard leaves (the white spots). Remember them as R-M-A. Note: Rhizopus and Mucor are saprophytes, but Albugo is an obligate parasite.
Albugo (Albugo candida) causes white rust / white blister disease on mustard, and yes, it is a Phycomycete. It is an obligate parasite, meaning it can only live on a living host. The 'white spots seen on mustard leaves' mentioned in NCERT are caused by Albugo. Do not confuse this with wheat rust, which is caused by Puccinia, a Basidiomycete.
Which one of the following statements is wrong?
Match List I with List II: List I: A. Rhizopus B. Ustilago C. Puccinia D. Agaricus List II: I. Mushroom II. Smut fungus III. Bread mould IV. Rust fungus
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Practically, yes, for NEET. NCERT uses the name Phycomycetes, but because members like Rhizopus and Mucor form a zygospore during sexual reproduction, the group is also called Zygomycetes in modern classification. Stick to the NCERT term Phycomycetes for NEET answers.
In aquatic habitats and on decaying wood in moist, damp places, or as obligate parasites on plants (like Albugo on mustard). They like water and moisture, which is why they are 'lower/algal' fungi.
Inside — endogenously, within a sac called the sporangium. This is different from Ascomycetes like Penicillium, whose conidia are made outside (exogenously). This inside vs outside point is a favourite NEET trap.
No. Albugo is an obligate parasite that causes white rust on mustard. In contrast, Rhizopus and Mucor are saprophytes (they feed on dead, decaying matter like bread and dung).
Ascomycetes (the sac-fungi). They are 'higher' than Phycomycetes, have SEPTATE mycelium, and make sexual ascospores in a sac called the ascus plus asexual conidia. See our Ascomycetes page next.
