||Newest Exam
radial symmetry -CORRECT ANSWER body plan in which any number of imaginary
planes drawn through the center of the body could divide it into equal halves
sessile -CORRECT ANSWER Describes an organism that remains attached to a
surface for its entire life and does not move
bilateral symmetry -CORRECT ANSWER Body plan in which only a single, imaginary
line can divide the body into two equal halves.
morula -CORRECT ANSWER A solid ball of cells that makes up an embryo; in humans,
this stage occurs within four days of fertilization.
blastula -CORRECT ANSWER A hollow ball of cells that marks the end of the cleavage
stage during early embryonic development in animals.
blastocoel -CORRECT ANSWER the fluid-filled cavity inside a blastula
gastrula -CORRECT ANSWER In animal development, a series of cell and tissue
movements in which the blastula-stage embryo folds inward, producing a three-layered
embryo, the gastrula.
blastopore -CORRECT ANSWER The opening of the archenteron in the gastrula that
develops into the mouth in protostomes and the anus in deuterostomes
archenteron -CORRECT ANSWER The central cavity in the gastrula stage of
embryological development; it is lined by endoderm and ultimately gives rise to the adult
digestive tract.
mesoderm -CORRECT ANSWER which germ layer gives rise to muscle (smooth and
striated), bone, cartilage, connective tissue, adipose tissue, circulatory system,
lymphatic system, dermis, genitourinary system, serous membranes, and notochord.
endoderm -CORRECT ANSWER Which germ layer gives rise to the stomach, the
colon, the liver, the pancreas, the urinary bladder, the epithelial parts of trachea, the
lungs, the pharynx, the thyroid, the parathyroid, and the intestines.
ectoderm -CORRECT ANSWER The surface ___________ develops into: epidermis,
hair, nails, lens of the eye, sebaceous glands, cornea, tooth enamel, the epithelium of
the mouth and nose.
, The neural crest of the _________ develops into: peripheral nervous system, adrenal
medulla, melanocytes, facial cartilage, dentin of teeth.
The neural tube of the ___________ develops into: brain, spinal cord, posterior
pituitary, motor neurons, retina.
protostome -CORRECT ANSWER an animal whose mouth is formed from the
blastopore
deuterostome -CORRECT ANSWER animal whose anus is formed from the blastopore
of a blastula
spiral cleavage -CORRECT ANSWER A type of embryonic development in
protostomes, in which the planes of cell division that transform the zygote into a ball of
cells occur obliquely to the polar axis, resulting in cells of each tier sitting in the grooves
between cells of adjacent tiers.
radial cleavage -CORRECT ANSWER A type of embryonic development in
deuterostomes in that the planes of cell division that transform the zygote into a ball of
cells are either parallel or perpendicular to the polar axis, thereby aligning tiers of cells
one above the other.
placozoa -CORRECT ANSWER What phylum is this microscopic simple creature
Porifera -CORRECT ANSWER what phylum associated with sponges, lack true tissues,
organs, mouth, and gut. Has choanocyte cells
Cnidaria -CORRECT ANSWER what phylum consisting of Anemones, Corals, and
Jellyfish. It has three types of cells: nematocyst for stinging, spirocyst for adhesion, and
ptychocyst for tube construction
Hydrozoa -CORRECT ANSWER what class in phylum cnidaria consists of hydra,
hydroids, portuguese man of war, and fire coral which alternates between polyp and
medusa stages
Scyphozoa -CORRECT ANSWER what class are jellyfish in. jellyfish are predominately
in the medusa stage
Anthozoa -CORRECT ANSWER What class are sea anemones and corals in? they are
in phylum cnidaria
Platyhelminthes -CORRECT ANSWER What phylum known for flatworms is ventrally
flattened and has an incomplete digestive tract.
Turbellaria -CORRECT ANSWER what class are Planarians in?