Chapter 9 Architectural Pattern Of An Animal Flashcards
Characterizes unicellular organisms. All life functions are confined within the boundaries of a single cell, the fundamental unit of life. Within a cell, protoplasm is differentiated into organelles capable of performing specialized functions.
Protoplasmic grade of organization
An aggregation of cells that are functionally differentiated. A division of labor is evident, so that some cells are concerned with,for example, reproduction, and others with nutrition. Some flagellates, such as Volvox, that have distinct somatic and reproductive cells are placed at the cellular level of organization. Many authorities also place sponges at this level.
Cellular grade of organization
An aggregation of similar cells into definite patterns or layers and organized to perform a common function, to form a tissue.
Cell-tissue grade of organization
An aggregation of tissues into organs. Organs are usually composed of more than one kind of tissue and have a more specialized function than tissue.
Tissue-organ grade of organization
Organs work together to perform some function, producing the highest level of organization.
Organ-system grade of organization
Multicellular animal (cellular grade of organization).
Metazoa
Cells grouped together and perform their common function as a coordinated unit
Tissue
Animals at or beyond the cell-tissue grade of organization
Eumetazoans
The specialized tissue of an organ as distinguished from the supporting connective tissue
Parenchyma (anything poured in beside)
Supporting connective tissue framework of an animal organ; filmy framework of red blood corpuscles and certain cells.
Stroma (bedding)
Any plane passing through the center divides a body into equivalent, or mirrored, halves.
Spherical symmetry
Applies to forms that can be divided into similar halves by more than two planes
Radical symmetry
A type of radial symmetry in which only two planes passing through the oral-aboral axis yield mirror images because some structure is paired
Biracial symmetry
Applies to animals that can be divided along a sagittal plane into two mirror portions (right and left halves)
Bilateral symmetry
The evolutionary process by which sensory organs and specialized appendages become localized in the head end of animals
Cephalization (head)
Designate the head end
Anterior
The opposite side of the head or the tail end
Posterior
The back or upper side
Dorsal
The front or belly side
Ventral
Refers to the midline of the body
Medial
The sides
Lateral
Parts further the middle of the body
Distal
Parts are nearer
Proximal
A fluid-filled cavity,shaped spherical and composed of a layer of cells
Blastocoel (gut hollow)
Embryonic stage, usually cap- or sac-shaped, with walls of two layers of cells surrounding a cavity (archenteron) with one opening (blastopore)
Gastrula
Two germ layers
Diploblastic
Third germ layer
Mesoderm
Without a coelom (common in flatworms and proboscis worms)
Acelomate (not cavity)
In lower animals, a spongy mass of vacuolated mesenchyme cells filling spaces between viscera muscles, or epithelial; in some, cell bodies of muscle cells. Also, the specialized tissue of an organ as distinguished from the supporting connective tissue (acoelomate)
Parenchyma (anything poured in beside)
Mesodermal cells line the outer edge of the blastocoel, leaving two body cavities: a persistent blastocoel and a gut cavity
Pseudocoelomate
Mesodermal cells fill the blastocoel, forming a solid band of tissue around the gut
Schizocoelous/enterocoelus/coeloniate body plan
A type of coelom formed by the outpouching of a mesodermal sac from the endoderm of the primitive gut
Enterocoel
