Questions with Correct Answers
Who is responsible for the experiments with tissue induction using salamander
embryos? - ANSWERSSpemann and Mangold
Which portion of a salamander gastrula was used in Spemann and Mangold's
experiments? - ANSWERSdorsal lip
Which historical idea is that the entire organism was in a miniaturized version within a
sperm or egg? - ANSWERSPreformation
Which historical idea is that an egg contains building material activated by sperm? -
ANSWERSepigenesis
A cell which has committed to a fate is determine by one of two processes which are? -
ANSWERSspecification induction
Which one of the two determination processes is usually irreversible? -
ANSWERSinduction
What are some morphogenetic determinants? - ANSWERStranscription and inducing
factors, direct activation, and repress genes at the correct times
Male and female gametes unite to form a? - ANSWERSzygote
Describe sperms relationship with egg activation? - ANSWERSit is not always required
What is it that prevents fertilization by another species? - ANSWERSspecies specific
recognition proteins
Why prevent polyspermy? - ANSWERSn + n = 2n
n + n +n...... = Xn (not good)
too many pairs can have negative effects
Which type of blocking polyspermy is an electrical potential charge change in the egg
membrane? - ANSWERSfast block
Which type of blocking of polyspermy is a cortical reaction that creates an osmotic
gradient to wash sperm away and cause the vitelline membrane to harden and
physically block sperm? - ANSWERSslow block
, Where do sea urchin fertilization occur? - ANSWERSexternally
What are small maneuverable cells? - ANSWERSblastomeres
With which stage is there no growth, just a big mass dividing to a group of normally
sized? - ANSWERScleavage and early development
What are the 2 types of polarities that can be established? - ANSWERSanimal pole,
vegetal pole
Which type of yolk distribution has very little yolk which is evenly distributed? -
ANSWERSisolecithal
Which type of yolk distribution has a moderate amount of yolk at the vegetal pole? -
ANSWERSmesolecithal
Which type of yolk distribution has lots of yolk at vegetal pole? - ANSWERStelolecithal
Which type of yolk distribution has a large centrally located yolk? -
ANSWERScentrolecithal
Which type of cleavage has lots of yolk, with cells sitting on top of an undivided yolk? -
ANSWERSmeroblastic
Which type of cleavage has cleavage furrows that extend completely through the egg? -
ANSWERSholoblastic
Which type of development has the embryo develop into a miniature adult? -
ANSWERSdirect development
Which type of development has multiple developmental stages? - ANSWERSindirect
development
What is the term where the mother nourishes the developing embryo? -
ANSWERSmatrotrophy
What is a cluster of cells, that is usually hollow? - ANSWERSblastula
Which stage has one layer of germ cells following cleavage? - ANSWERSblastulation
What is the conversion of the spherical blastula into a 2 or 3 layered embryo? -
ANSWERSgastrulation
What is the internal pouch formed in gastrulation? - ANSWERSarchenteron
What is the opening to the archenteron? - ANSWERSblastopore