Slime Moulds
Slime molds are a diverse group of organisms that are classified as protists, which means they are not
plants, animals, or fungi. They are unique in their ability to exist as single-celled organisms or as
multi-cellular, amoeba-like structures known as plasmodia.
Slime molds can be found in a variety of habitats, including forests, grasslands, and even on decaying
logs in suburban areas. They are important decomposers, breaking down dead plant and animal matter
and recycling nutrients back into the ecosystem.
Slime moulds are under the super group Amoebozoa.
Characteristics
1. Most slime moulds are small, about a few centimetres, largest can cover about 30m², making
them largest undivided cells known.. They are over 900 species
2. They have bright colors like yellow, white and brown.A slime mold spends most of its life as
a lumpy mass of protoplasm, called a plasmodium, that moves and eats like an amoeba. It
may be white, yellow, orange, or red. The color of a particular species can vary slightly with
temperature, pH, and the substances the plasmodium eats.
3. They possess both animals and plants characteristics.
4. Slime Moulds were classified under fungi because they produce spores.
5. They are saprophytic and lack chlorophyll. They feed on microorganisms such as bacteria,
fungi and yeasts and decompose dead organic matter
6. Spores have a protective layer known a spore coat. Made up of other organic molecules and
proteins to prevent them from damage.
7. They have diploid nuclei.
8. Nutrition is phagocytic but mostly saprophytic, some are parasitic found in the roots of
cabbage.
9. Slime molds have amoeba-like characteristics, meaning they can change shape and move by
extending and contracting their cytoplasmic extensions, known as pseudopodia.
10. Some slime molds can form fruiting bodies, which are structures that produce and release
spores for reproduction.
11. When food is depleted, cellular slime molds aggregate into a mass of cells that behaves as a
single unit called a slug.
Slime moulds are classified into two
 Plasmodial slime molds, also known as Myxomycetes, are a group of slime molds
that are characterized by their large, multinucleate, amoeboid plasmodia. The
plasmodial stage of these slime molds is a single, visible mass of cytoplasm that can
grow and spread over a large area, engulfing food particles and forming complex
structures, such as fruiting bodies, for reproduction.The plasmodium of plasmodial
slime molds is capable of moving and changing shape in response to environmental
cues, such as light and moisture. It also has the ability to fuse with other plasmodia,
allowing the slime mold to grow and spread over large distances.Plasmodial slime
molds are found in a variety of habitats, including forests, grasslands, and wetlands.
They play an important ecological role as decomposers, breaking down dead plant
and animal matter and recycling nutrients back into the ecosystem. One of the most
fascinating aspects of plasmodial slime molds is their ability to form fruiting bodies,
which are structures that produce and release spores for reproduction. These fruiting
bodies can take on a variety of shapes and colors, ranging from small, spherical
structures to large, colorful stalks. The spores produced by the fruiting bodies can be
dispersed by wind or other means, allowing the slime mold to colonize new areas.

Cellular Slime moulds: Cellular slime molds, also known as dictyostelids, are a group
of slime molds that are characterized by their individual amoeboid cells that can
aggregate together to form a multicellular structure called a pseudoplasmodium. The
pseudoplasmodium moves as a single unit, feeding on bacteria and other
microorganisms. When the food supply becomes scarce, the pseudoplasmodium
undergoes a developmental stage and forms a fruiting body for reproduction. The
fruiting body can take on a variety of shapes and colors, ranging from small, spherical
structures to stalk-like forms. The individual cells of cellular slime molds are capable
of moving and changing shape in response to environmental cues, such as chemicals
and light. They can also communicate with each other through chemical signals,
coordinating their movements and behaviors to form the pseudoplasmodium and
eventually the fruiting body.Cellular slime molds are found in a variety of habitats,
including soil and leaf litter in forests and grasslands. They play an important
ecological role as decomposers, breaking down dead plant and animal matter and
recycling nutrients back into the ecosystem.One of the most interesting aspects of
cellular slime molds is their ability to form multicellular structures and exhibit
coordinated behavior, despite being composed of individual cells. This has led
scientists to study them as a model for understanding the evolution of multicellularity
and the mechanisms of cell communication and cooperation.
Life Cycle of slime mould.
Plasmodial slime mould: The life cycle of a plasmodial slime mold, also known as Myxomycetes,
involves several distinct stages:
1. Spore germination: The life cycle begins when a spore germinates, with single haploid nucleus
producing a small, motile cell called a swarm cell.
2. Swarm cell stage: The swarm cells move and feed on bacteria and other microorganisms in the
environmentWhen the food is scarce they fuse and become diploid zygotes. The diploid cell divides
by mitosis. Each nuclei divides by mitosis form a larger, multinucleate mass of cytoplasm called a
plasmodium.
3. Plasmodial stage: The plasmodium is a visible mass of cytoplasm that is capable of growing and
spreading over a large area. It feeds on microorganisms and can move and change shape in response
to environmental cues.
4. Fruiting body formation: When the plasmodium has consumed enough food and environmental
conditions become unfavorable, it undergoes a developmental stage and forms a fruiting body. The
fruiting body can take on a variety of shapes and colors, ranging from small, spherical structures to
large, colorful stalks.The nuclei divides by Meioses becoming haploid cell membranes forms around
each nucleus and finally the cells transform into haploid spores.
5. Spore production: The fruiting body produces and releases haploid spores for reproduction. The
spores are dispersed by wind or other means and can germinate to begin the life cycle anew.
Cellular slime mould:
The life cycle of a cellular slime mold, also known as dictyostelid, involves several distinct stages:
1. Single cell stage: Cellular slime molds exist as individual amoeboid cells that feed on bacteria and
other microorganisms in the soil and leaf litter.
2. Aggregation stage: When food becomes scarce, the individual cells aggregate together to form a
multicellular structure called a pseudoplasmodium. The pseudoplasmodium moves as a single unit,
feeding on microorganisms.
3. Slug stage: As the pseudoplasmodium grows and develops, it forms a slug-like structure. The slug
moves as a coordinated unit and is able to respond to environmental cues, such as light and
temperature.
4. Fruiting body formation: When the slug reaches a suitable location, it undergoes a developmental
stage and forms a fruiting body. The fruiting body can take on a variety of shapes and colors, ranging
from small, spherical structures to stalk-like forms.
5. Spore production: The fruiting body produces and releases spores for reproduction. The spores are
dispersed by wind or other means and can germinate to begin the life cycle anew.