C) The earthworm, because it can contract and expand its muscles to burrow down though the watery solution
A) The earthworm because it uses two sets of muscles to help it moves through the watery solution
D) The nematodes, because it can move its paddle-like appendages on its segments to help it move through the watery solution
B) The nematode, because it is whip like motion will easily propel it through the watery solution
B) anterior; dorsal
A) Posterior; Dorsal
D) anterior; Ventral
C) posterior; ventral
B) are heterotrophic
D) obtain food by absorption
A) are prokaryotic
C) have cell wallls made of chitin
C) There is no body cavity
A)The opening formed during gastrulation becomes the mouth
D) There is not endoderm
B)The opening formed during gastrulation becomes the anus
B) Deutorostome have only two tissue layers.
D) The opening that forms during deuterostome gastrulation becomes the mouth
C) The opening that forms during deuterostome gastrulation becomes the anus
A) Deuterostome lack true tissue
A) Sea stars (Echinodermata)
D) Sponges (Porifera)
C) Sea anemones (Cnidaria)
A) Sea stars (Echinoderma)
D) Octopus (Mollusca)
D) a mesoderm; a blastula
B) an ectoderm; an endoderm
C) an endoderm; an ectoderm
A) an ectoderm; a blastula
D) The haploid larvae develop intp diploid adults.
A) Homeotic genes play important roles in the development of an organisms from zygote to adult.
C) The cell walls are diverse in structure but are composed of chitin.
B) The organism requires carbon diaxide as an essential nutrient
C) a massive volcanic eruption nearly wiped out life on earth.
A) All modern species of animals suddendly appeared
B) animals rapidly diversified in the oceans
D) Great forests produced peat layers that were later transformed into coal.
C) Solar flared led to increase UV radiation intenity, which in turn promoted a high rate of mutations. This led to rapid diversification of animals.
B) A great surge of volcanic activity was triggered by significant movement of the continetal plates and possibly by an asteroid impact.
A) Complex predator-prey relationships and increased atmospheric oxygen levels promoted animal diversification.
D) The massive growth of swamp vegetation depleted the atmosphere's carbon dioxide and eventually cooled down the Earth's climate.
A) are vertebrates
D) are really colonies of protists cells
C) are choanoflagellates
B) are invertebrates
C) a fish
B) A sea anemone
A) a worm
D) a lobster
B) a tennis racket
D) an apple pie
A) a glove
C) a pair of sun glasses
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