topic 12- what are animals? Flashcards
animals are ___ eukaryotes
multicellular
animal bodies are held together by an ____ ___ composed of structural proteins such as ____
extracellular matrix (ECM) collagen
true tissues are separated by ___ ___
membrane layers
animals are ____trophic and capable of ___ in at least one stage of life cycle
chemoheterotrophic
movement
What do hox genes do?
control anterior –> posterior developmental sequence of embryo
(differentiation of genes)
diploid zygote undergoes ___cell divisions (cleavage) –> 8 cell stage –> (cleavage) —>____(hollow ball)—> (gastrulation) –> _____
mitotic
blastula
gastrula
during development, ___ ___ give rise to tissues & organs of the animal embryo
germ layers
protostomes have ___ cleavage, and ____ cells
deuterostomes have ___ cleavage and ____ cells
spiral, determinant
radial, indeterminant (remain stem cells for longer)
Protostomia: the first invagination of the ___ becomes the ___
-Deuterostomia: the 2nd invagination of the ___ becomes the ___
- gastrula(blastopore), mouth
- gastrula, mouth (first is anus)
Give examples of indirect and direct development in animals
- direct: human (embryo gradually straight to adult form)
- indirect: caterpillar –> butterfly
eumetazoan are animals with ____
- ___ are the outgroup (animals without true tissues- metazoan)
true tissues
porifera
radiata are _____( have __ embryonic germ layers)
diploblastic (2)
bilaterian are _____(have __ embryonic germ layers)
triploblastic (3)
____ animals are often sessile
_____ animals often move actively and have a central nervous system
radial
bilateral
define cephalization
in bilateral animals
- concentration of sensory organs in head (adapted for forward movement)
Radial animals have a ___ nervous system
bilateral animals have a ___ nervous system
nerve net
central (CNS)
most triploblastic animals have a fluid-filled ___ ___ (___) which is derived from the mesoderm
body cavity (coelom)
define a pseudocoelomate
animals lack complete mesodermal lining, have a pseudo coelom
triploblastic animals that lack a body cavity are called ____
acoelomates
list 3 functions of a coelom
- cushions internal organs from blows to outside body
- allows internal organs to shift w/o deforming outside of body
- fluid-filled cavity can be used a a hydrostatic skeleton
animalia is ___phyletic
mono
___are the basal animal of animals (least ___)
sponges
derived
