Intro To Animal Diversity Flashcards
The presence of what two tissues are the unique defining characteristic of animals?
Nervous and muscular tissue.
What do the nutritional modes of plants and animals differ?
Animals are heterotrophs, where as plants are autotrophs.
What are tissues?
A tissue is a group of cells consisting of one or more cell types that together perform a specialized function.
Describe cleavage.
After a sperm fertilizes an egg, the zygote undergoes rapid cell division called cleavage.
Describe blastula.
A hallow ball of cells that marks the end of the cleavage stage during early embryonic development in animals.
Describe gastrulation.
A series of cell and tissue movements in which the blastula-stage embryo folds inward, producing a three-layered embryo, the gastrula.
Describe gastrula.
An embryonic stage in animal development encompassing the formation of three layers: ectoderm, mesoderm, and endoderm.
Describe Archenteron.
The endoderm lined cavity, formed during gastrulation, that develops into the digestive tract of an animal.
Describe protostome.
Developmental mode distinguished by the development of the mouth from the blastopore. Often also characterized by spiral cleavage and by the body cavity forming when solid masses of mesoderm split.
Describe deuterostome.
A developmental mode distinguished by the development of the anus from the blastopore. Often also characterized by radial cleavage and by the body cavity forming as out pockets of mesodermal tissue.
How do larvae and juveniles differ?
A larva is sexually immature and morphologically distinct from the adult. The juvenile is also sexually immature but resembles an adult.
Describe the major events of the Neoproterozoic era.
Contains early members of the animal fossil record that include Ediacaran biota, which dates from 565-550MYA.
What is meant by Ediacaran biota?
An early group of soft bodied, multicellular eukaryotes known from fossils that range from 565-550MYA.
Describe the events of the Paleozoic Era.
The Cambrian explosion occurred, animal diversity continued but was punctuated by mass extinctions. Vertebrates made the transition to land around 360 MYA.
What is the Cambrian explosion?
A relatively brief time in geologic history when many present-day phyla of animals first appeared in the fossil record. This burst of evolutionary change occurred about 535-525 MYA and saw the emergence of the first large, hard bodied animals.
Describe the major events of the Mesozoic Era.
Coral reefs emerged, dinosaurs were the dominant terrestrial vertebrates, first mammals emerged, flowering plants and insects diversified.
Describe the major events of the Cenozoic Era.
Followed mass extinctions of both terrestrial and marine animals. Mammals increased in size and exploited vacated ecological niches, the global climate cooled.
What is a body plan?
In multicellular eukaryotes, a set of morphological and developmental traits that are integrated into a functional whole-the living organism.
What is radial symmetry?
Symmetry in which the body is shaped like a pie or barrel (lacking a left or right side) and can be divided into mirror-imaged halves by any plane through its central axis.
What is bilateral symmetry?
Body symmetry in which a central longitudinal plane divides the body into two equal, but opposite halves.
What do bilaterally symmetrical animals have in common?
Have a dorsal(top) and a ventral(bottom) side.
Have a right and left side.
Anterior(head) and posterior (tail) ends.
Cephalization (development of heads.)
How do types of movement compare between radial and bilaterally symmetrical animals?
Bilateral animals will move often and have a central nervous system.
What is the ectoderm? Endoderm? Mesoderm?
Ectoderm is the germ layer covering the embryo’s surface. The endoderm is the innermost germ layer. The mesoderm is the intervening germ layer.
What is the difference between coelomates, psuedocoelomates, and acoelomates?
Coelomates are animals that posses a true coelom. Psuedocoelomates are animals that posses a pseudocoelom. Acoelomates are animals that lack a body cavity.
