Lecture 16, 17, & 18 Flashcards
What does chemoheterotrophic mean
cannot make own carbon based food source, must consume other organisms
What happens during sexual reproduction
motile haploid sperm fertilizes larger non-motile haploid egg to make diploid zygote
What are protosomes
a new row of cells slightly twisted off center
spiral cleavage
determinate: new cell forms part of later embryo
What are deuterostomes
each cell division stacks the new cells directly above the previous ones
radial cleavage
indeterminate: early embryonic cells not differentiated (could split aka identical twins)
What is protostomia
first invagination of the gastrula becomes the mouth
What is Deuterostomia
second invagination becomes the mouth
What is a homeobox
highly conserved nucleotide sequence
control anterior to posterior developmental sequence of embryo
What are Hox genes
homeobox containing genes
What is cephalization
the development of a head
what is parazoan design
specialized cells for different function
what is eumetazoan design
specialized cells aggregated into distinct tissues; more advanced designs (organs)
what layers does a diploblastic organism have
endoderm & ectoderm
triploblastic
endo-, ecto-, and mesoderm
what are coelomates
possess a true coelom
have body cavity called coelom
function of a hemocoel
-primary body cavity of most invertebrates
circulation, nutrient transport, waste removal