Topic 7 (2)

involves fusion of compatible nuclei from 2 parent cells

Sexual

Male gametangia known as

antheridium

Female gametangia known as

oogonium

The process of sexual reproduction involves three phases

• Plasmogamy

• Karyogamy

• Meiosis

Anastomosis of two cells or gametes and fusion of their protoplasts takes place

Plasmogamy

In plasmogamy, two ___________________, are brought together but the nuclei will ______

nuclei of opposite sexes (compatible) nuclei)………………………….will not fuse

Various methods by which compatible nuclei are brought together in plasmogamy. Some are:

•Gametic copulation

•Gamete-gametangial copulation

•Gametangial copulation

•Somatic copulation

•Spermatization

Motile gametes are called

Planogametes

There are three different types of planogametic copulation.

• Isogamy

• Anisogamy

• Heterogamy or Oogamy

The fusion of two gametes, one or both of which are motile is called

Planogametic Copulation

morphologically similar but compatible type of gametes unite to form a motile zygote.

Isogamy

Union of one larger gamete with another smaller gamete.

Anisogamy (resultant zygote is motile)

The zygote resulting from isogamous or anisogamous planogametic copulation forms a

Resting sporangium

A non-motile female gamete (oosphere) is fertilized by a motile male gamete.

Heterogamy or Oogamy (=oospores)

A resistant structure and resting spore

Oospores

Oospores germinate and produce ___________ directly

Mycelium

Isogamy example

Synchytrium

Anisogamy example

Blastocladiales

Heterogamy example

Chytridiomycetes

In this method the male gamete (antheridium) and the female gamete (oogonium) come in contact and one or more nuclei from the male gamete enter the female gamete, oogonium dissolved in the intervening wall through a pore or through a fertilization tube

Gametangial contact

In ______ the gametangia actually fuse or lose their identify during the sexual act

no case

Example of gametangial contact

• Fungi in Peronosporales

• Ascomycota

This is a process of fusion of entire contents of the two mating gametangia

Gametangial copulation

Two types of Gametangial copulation

• Anisogametangial copulation

• Isogamous copulation

Fusion between unequal gametanagia. Forms a resting sporangium

Anisogametangial

Two morphologically similar gametangial hyphae come in contact, the wall at the point of contact dissolves and the contents mix in the cell thus formed. = Zygospores

Isogamous copulation

Anisogametangial copulation example

Aquatic fungi

Isogamous copulation example

Mucor, rhizopus, phycomyces

Some fungi like rusts bear numerous minute, nonmotile uninucleate, male cells called

Spermatia

Spermatia are produced in spiral receptacles called

Spermagonia

Spermatia is carried by what to the female gametangium?

• Insects

• Wind

• Water

Spermatia carried by insects, wind or water to the female gametangium, which is usually a ___________ to which they become attached.

special receptive hypha (or trichogyne)

In ____________ no sex organs are produced and somatic cells function as gametes.

somatogamy

Somatogamy is common in ______________ fungi.

Ascomycota and Basidiomycota

nonmeiotic spores produced inside specials sacs called asci

Ascopores

Ascopores are produced by? and inside specials sacs called?

Produced by members of ascomycota inside asci

non-motile meiospore formed on short outgrowths of club-shaped structures called basidium

Basidiospores

Basidiospores are formed on short outgrowths of club shaped structure called

Basidium

arge, thick-walled spores formed at the tips of 2 sexually compatible hyphae

Zygospore

Zygospore is produced by?

members of zygomycota

spores formed within a specialized female structure (oogonium) after fertilization of eggs by male gametes formed in an antheridium

Oospores