Biology 1407 exam test quizzes and
answers graded A+
Acoelomate - ANS✅✅Lack a body cavity between digestive cavity (from endoderm) and outer
body wall (ectoderm). Ex: planarians
Coelomate - ANS✅✅Have a true coelom, a body cavity completely lined by tissue derived from
mesoderm. Ex: earthworms
Pseudo coelomate - ANS✅✅Have a body cavity lined by tissue derived from mesoderm and by
tissue derived from endoderm. Ex: roundworms.......
"pseudo"=false
Coelom (body cavity) - ANS✅✅True body cavity is completely lined with and derived from
mesoderm (coelomates/triploblastic animals). Fluid or air filled space located between digestive
tract and outer body wall.
Ectoderm - ANS✅✅Germ layer covering the surface of the embryo, gives rise to outer covering
(i.e.: body wall) and central nervous system in some animals.
Endoderm - ANS✅✅Innermost germ layer, lines the pouch that forms during gastrulation (the
archenteron) and gives rise to the lining of the digestive tract (or cavity) and most organ of
vertebrates.
Mesoderm - ANS✅✅3rd germ layer that fills space between ectoderm and endoderm found only
in bilateral animals. Forms muscles and most other organs
Triploblastic - ANS✅✅3 germ layers (ecto, endo, meso). Bilateria. Ex: flatworms, arthropods,
vertebrates
Diploblastic - ANS✅✅2 germ layers (ecto, endo). Radiata. Ex: Cnidarians
Cleavage - ANS✅✅After a sperm fertilizes an egg, the zygote undergoes mitotic cell divisions
without cell growth between the divisions. Leads to formation of blastula.
, Spiral cleavage - ANS✅✅Determinate. Protostome development. Ex: molluscs and annelids
Radial cleavage - ANS✅✅Indeterminate. Deuterstome development. Ex: echinoderms and
chordates
Blastula - ANS✅✅Multicellular, hollow-ball stage that surround a cavity called blastocoel.
Blastopore - ANS✅✅Opening of archenteron that typically develops into the anus in
deuterostomes and the mouth in protostomes.
Gastrulation - ANS✅✅Following blastula stage, layers of embryonic tissues develop into adult
body parts. One end of the embryo folds in, expands, eventually fills blastocoel. Results in gastrula.
Gastrula - ANS✅✅Resulting developmental stage after gastrulation with different embryonic
tissue layers (ecto, endo).
Gastrovascular cavity - ANS✅✅Digestive compartment with a single opening (pouch). Functions in
digestion as well as distribution of nutrients throughout the body
Archenteron - ANS✅✅Blind pouch formed by gastrulation opens to the outside via blastopore.
Becomes the gut.
Metamorphosis (simple) - ANS✅✅Larvae undergoes to become a juvenile (nymph). Not yet
sexually mature.
Metamorphosis (complete) - ANS✅✅Does not involve a nymph stage. Not yet sexually mature.
Bilateral symmetry - ANS✅✅Divided along the vertical plane at the midline to create 2 halves.
Usually highly motile with CNS. Bilateria exhibit.
Radial symmetry - ANS✅✅Divided equally by any longitudinal plane passing through the center
axis. Have oral and aboral sides and are often sessile or planktonic. Radiata exhibit.
answers graded A+
Acoelomate - ANS✅✅Lack a body cavity between digestive cavity (from endoderm) and outer
body wall (ectoderm). Ex: planarians
Coelomate - ANS✅✅Have a true coelom, a body cavity completely lined by tissue derived from
mesoderm. Ex: earthworms
Pseudo coelomate - ANS✅✅Have a body cavity lined by tissue derived from mesoderm and by
tissue derived from endoderm. Ex: roundworms.......
"pseudo"=false
Coelom (body cavity) - ANS✅✅True body cavity is completely lined with and derived from
mesoderm (coelomates/triploblastic animals). Fluid or air filled space located between digestive
tract and outer body wall.
Ectoderm - ANS✅✅Germ layer covering the surface of the embryo, gives rise to outer covering
(i.e.: body wall) and central nervous system in some animals.
Endoderm - ANS✅✅Innermost germ layer, lines the pouch that forms during gastrulation (the
archenteron) and gives rise to the lining of the digestive tract (or cavity) and most organ of
vertebrates.
Mesoderm - ANS✅✅3rd germ layer that fills space between ectoderm and endoderm found only
in bilateral animals. Forms muscles and most other organs
Triploblastic - ANS✅✅3 germ layers (ecto, endo, meso). Bilateria. Ex: flatworms, arthropods,
vertebrates
Diploblastic - ANS✅✅2 germ layers (ecto, endo). Radiata. Ex: Cnidarians
Cleavage - ANS✅✅After a sperm fertilizes an egg, the zygote undergoes mitotic cell divisions
without cell growth between the divisions. Leads to formation of blastula.
, Spiral cleavage - ANS✅✅Determinate. Protostome development. Ex: molluscs and annelids
Radial cleavage - ANS✅✅Indeterminate. Deuterstome development. Ex: echinoderms and
chordates
Blastula - ANS✅✅Multicellular, hollow-ball stage that surround a cavity called blastocoel.
Blastopore - ANS✅✅Opening of archenteron that typically develops into the anus in
deuterostomes and the mouth in protostomes.
Gastrulation - ANS✅✅Following blastula stage, layers of embryonic tissues develop into adult
body parts. One end of the embryo folds in, expands, eventually fills blastocoel. Results in gastrula.
Gastrula - ANS✅✅Resulting developmental stage after gastrulation with different embryonic
tissue layers (ecto, endo).
Gastrovascular cavity - ANS✅✅Digestive compartment with a single opening (pouch). Functions in
digestion as well as distribution of nutrients throughout the body
Archenteron - ANS✅✅Blind pouch formed by gastrulation opens to the outside via blastopore.
Becomes the gut.
Metamorphosis (simple) - ANS✅✅Larvae undergoes to become a juvenile (nymph). Not yet
sexually mature.
Metamorphosis (complete) - ANS✅✅Does not involve a nymph stage. Not yet sexually mature.
Bilateral symmetry - ANS✅✅Divided along the vertical plane at the midline to create 2 halves.
Usually highly motile with CNS. Bilateria exhibit.
Radial symmetry - ANS✅✅Divided equally by any longitudinal plane passing through the center
axis. Have oral and aboral sides and are often sessile or planktonic. Radiata exhibit.
