how rhizopus reproduce themself
Answers
Reproduction in Rhizopus: life cycle
1) Fragmentation
2) Asexually method: Sporangiospore
formation and chalmydospore
formation
3)Sexual method: gamentagial
copulation
Fragmentation:
Disjoining of hyphae gives new organism.
It is one of the common mode of reproduction in Rhizopus
Asexual reproduction in Rhizopus:
It occurs during favorable condition
Aerial hyphae develop from internode and arise to certain height
The nuclei and cytoplasm push more and more towards the apical side, consequently the apex of the aerial hyphae swells up.
The swollen part enlarges and develops into a large round sporangium
Sporangium differentiates into two region; multinucleated sporoplasm and vaculated columellaplasm
Nucleus in sporoplasm divides rapidly, and each nuclei gather some cytoplasm and transform into spongiospore
After maturity columella collapsed releasing sporangiospore in atmosphere
Sporangiospore attached to substratum and germinates to give mycellium
During unfavorable condition, septum formation occurs in mycelium and each intercalary mycelium give rise to thick resting spore known as chlamydospore.
Sexual reproduction in Rhizopus:
Sexual reproduction takes place during unfavourable condition by means of gametangial copulation.
Most Rhizopus are heterothallic
When two mycelium of opposite strain come close to each other, each mycelium produce small outgrowth, called progametangia
The apical region of the two progametangia come in close contact and cytoplasm of each progametangium push more and more towards the apical region which swell up with dense protoplasm.
The apical region is known as gametangia and basal region is known as suspensor
The protoplasm in gametangia fuses to from zygospore
Zygospore is a resting spore
During favorable condition, spore wall rupture and form germ tube which elongates to form promycellium
Promycellium have two region; germsporangiophore and germsporangium
Nucleus in germsporanium divides by meiosis forming haploid nuclei, which gather cytoplasm and behaves as spore.
The haploid spore are released and germinates to give mycellium
