Holoblastic cleavage (complete division of the egg) occurs ina) birds.b) sea urchins.c) reptiles.d) fishes

Holoblastic cleavagea) is the incomplete division of the egg, which occurs in species with yolk-­‐rich eggs.b) is the complete division of the egg.c) only occurs in eggs with no yolk.d) only occurs in eggs with no polarity.16. Which of the following has a gastrovascular cavity?a) Earthwormb) Flatwormc) Nematode wormd) Round worm17. Which of the following is an osmoconformer?a) A freshwater fishb) A sea anemonec) A marine bony fishd) An anadromous fish18. Reptiles excrete uric acid becausea) it is more toxic than ammonia.b) it has a low energetic cost.c) their eggs are not permeable to liquid.d) they live on land.19. A brachiopod can be distinguished from a bivalve by the presence ofa) two hinged shells.b) a digestive system with separate mouth and anus.c) a lophophore.d) suspension feeding.20. Sponges are most accurately described asa) marine predators.b) marine filter feeders.c) freshwater scavengers.d) aquatic filter feeders.[PTO]21. Which of the following statements is NOT true?a) Genes code for proteins.b) A sequence of four DNA bases codes for an amino-­‐acid.c) Humans have 46 chromosomes.d) DNA variation arises because of mutations.22. The similarities between sugar gliders and flying squirrels are due toa) paedomorphosis.b) heterochrony.c) convergent evolution.d) polyploidy.23. Which of the following is not an isotope commonly used in radiometric dating?a) Carbon 14b) Uranium 238c) Potassium 40d) Nitrogen 1424. Fossilsa) are mostly well preserved.b) have mostly all been found.c) rarely have soft parts preserved.d) are known from most extinct species.25. In development, pattern formation is controlled bya) homeopathic genes.b) homeotic genes.c) homolytic genes.d) homeostatic genes.26. Which hormone of the adrenal gland promotes the short term stress response ("fightor flight"):a) epinephrineb) thyroxinec) testosteroned) cortisol27. An unequal distribution of ions inside and outside of a nerve cell is essential forgenerating its resting membrane potential. At rest there isa) a higher concentration of K + inside the cell.b) a higher concentration of K + outside the cell.c) a higher concentration of Na + inside the cell.d) a higher concentration of Cl -­‐ inside the cell.28. In nerve cells the stimulus amplitude is encodeda) in the size (amplitude) of the action potential.b) in the frequency of action potentials.c) in the duration of the action potential.d) in the resting membrane potential.[PTO]29. Odorants activate olfactory receptor cellsa) by binding to odorant receptors in the membrane.b) by binding to receptors in the cytoplasm.c) by bending of sensory cilia.d) by changing gene transcription.30. Thalamus and hypothalamus are part of thea) forebrain.b) midbrain.c) hindbrain.d) spinal cord.

Which of the following describes the patterns of cleavage of an animal egg?Multiple choice question.They vary in invertebrates but are identical in all vertebrates.They vary among animal phyla.They are the same in all animal phyla.

Holoblastic cleavage occurs in eggs containing which of the following?Multiple choice question.Yolk-richModerate to little yolkNo yolk

Indicate whether each of the following would result in holoblastic cleavage or merolastic cleavage.telolecithal eggsisolecithal eggsmesolecithal eggsradial cleavagespiral cleavagecentrolecithal eggsrotational cleavagediscoidal cleavageechinodermsannelidsflatwormsinsectsamphibiansmost invertebrate phylafishreptilesmammalscomplete cleavagesyncytial cleavagebirds

A mammalian egg undergoes Blank______ cleavage, forming a structure called a Blank______.Multiple choice question.meroblastic; blastocystmeroblastic; blastodischoloblastic; blastocystholoblastic; blastodisc