Lab 2- Natural selection/Starfish/Adaption Flashcards
what are the results of natural selection simulations
as time goes on, the black moths are being selected FOR which means they are being picked LESS than the white moths
what evidence suggests black moths survive better than white moths (NS)
- they have a higher chance of survival
- one pop became fixed
what is the trend seen in the genetic drift simulations
there is NO trend for genetic drift as it’s based on a random event
why is there no trend in the genetic drift simulation
- there is no direction for the trend
- groups had differing results for what survived better
true or false
natural selection is a directional trend
YES
what phylum do sea stars belong to
Echinodermata
what two phyla are deuterostomes
Echinodermata and Chordates
the water vascular system is used for
- locomotion
- feeding
- gas exchange
do phylum Echinodermata have a complete digestive tract
YES
what features make the body wall of the sea star
- epidermis
- endoskeleton
epidermis
body covering on all surfaces of sea star
endoskeleton is composed of
- dermal ossicles
- calcareous spines
dermal ossicles are located
embedded in the epidermis
calcareous spines are the
projections outward from the surface
what makes up the oral surface
- mouth
- tube feet (podia)
the oral surface is the
underside of the sea star(
mouth is located
in the center of the oral surface
tube feet (podia) are contained
within grooves along each arm
what do the tube feet have at each end
a sucker-like distal tip
what makes up the aboral surface
- eyespots
- madreporite
- dermal branchiae
- pedicellariae
the aboral surface is the surface that
is typically exposed (opposite the oral/mouth side)
eyespots are found
at the tip of each arm
what are the sensory disks called
eyespots
madreporite is located
just off center from the aboral axis
dermal branchiae extend through
the body wall from the coelom
dermal branchiae are
bladder like structures
where are gases exchanged in the sea star
Dermal branchiae
pedicellariae are found
randomly over the external surface of the epidermis
coelom
fluid-filled or air-filled body cavity that separates the digestive tract from the endoskeleton body covering
what makes up the digestive system
- pyloric ceca
- pyloric stomach
- cardiac stomach
pyloric ceca are located
aborally in the arms
pyloric stomach is located
on the aboral side of the cardiac stomach
how would the pyloric stomach be described
thin-walled and star-shaped sac
the pyloric ceca are
paired digestive glands