Evolution of Multicellularity
Most prokaryotes are unicellular, those that are multicellular show
What is simple multicellularity?
This is limited by the surface area: volume ratio
What is cell size?
Belong to the complex multicellular category, this is a land plant in the Archaeplastids
What is green algae?
An element required by complex multicellularity
What is oxygen?
These cells are the functional unit of the nervous system
What are nerve cells or neurons?
Nucleus divides (mitosis) but cell does not divide (no cytokinesis), cell gets larger and has multiple nuclei
What is coenocytic organisms?
This type of cellularity requires hollow structures or buried cells
What is multicellularity?
A specialized intercellular connection between a multitude of animal cell-types. They directly connect the cytoplasm of two cells.
What is gap junctions?
These record the evolution of large and complex multicellular organisms.
What are fossils?
This type of neurons signals a muscle or gland to cause a response in the body.
What are motor neurons?
This type of cellularity arose several times in evolution
What is complex multicellularity?
Molecules move through organisms at rates beyond those possible by diffusion across a concentration gradient
What is bulk flow?
These are co-axial membranous channels that cross walls of adjacent plant cells, linking the cytoplasm, plasma membranes and endoplasmic reticulum (ER) of cells and allowing direct cytoplasmic cell-to-cell communication of both small molecules and macromolecules
What is plasmodesmata?
This field of research looks at both individual development and evolutionary patterns in an attempt to understand the developmental changes that allowed organisms to diversify and adapt to changing environments.
What is evolutionary-developmental biology (also referred to as evo-devo)?
This type of neuron receives and transmits information about an animal’s environment or its internal psychological state
What are sensory neurons?
This type of organism has evolved independently at least six times
What is complex multicellularity?
This is the random motion of molecules
What is diffusion?
This provides plant cells the structural and mechanical support but does not allow plant cells to move. Animal cells do not have this.
Cell wall
Complex multicellular organisms evolved here first
What is water? (Complex multicellular organisms evolved in water before they evolved on land, as ancestral plants evolved the capacity to photosynthesize surrounded by air rather than water.)
These are the three types of neurons
What are interneurons, sensory neurons, and motor neurons?
This type of cellularity requires the adhesion of cells although there is little cell differentiation
What is simple multicellularity?
Cells rely on diffusion for
What is nutrients, oxygen, and waste disposal?
They are a group of living organisms which are classified in their own kingdom. This means they are not animals, plants, or bacteria. They are usually classified in four divisions: the Chytridiomycota, Zygomycota, Ascomycota, and the Basidiomycota.
What is fungi?
This is a benefit of multicellularity
What is allowing for greater diversity of structure and function?
This part of the nervous system consists of a collections of nerve cell bodies that integrate and process information
What are ganglia?