animal diversity + vertebrates Flashcards
what separates animals from plants?
can’t make their own food, no cell wall, cell junctions hold cells in place for communication
suspension feeding
filtering particles from surrounding water
bulkfeeding
eating large food pieces
fluid feeding
sucking fluid out of an animal or sap (think of a spider)
true or false: animals rely on absorptive nutrition
true
what is needed for movement?
muscle and nerve cells organized into tissue
muscle cells are unique to (blank)
animals
why do animals need to move?
find food and run
what systems are needed for movement?
specialized sensory structure + nervous system
sessile species like barnacles have (blank) for moving
appendages or a swimming larval stage
do all animals reproduce sexually
the vast majority of them do
what are the characteristics of the sperm and egg in animals?
the sperm is small and mobile while the egg is large
internal fertilization is common in (blank) species
terrestrial
why is internal fertilization common?
sperm needs a fluid to get to the egg
some animals do reproduce asexually, what are the benefits?
- don’t have to find another mate
- every individual can reproduce
- population increases rapidly
metamorphosis:
developmental phenomena where animal changes from a juvenile to adult
what are the advantages of metamorphasis?
reduces competition and facilitates dispersal (like fruit!)
multicellular animals emerged at the end of what eon?
proterozoic (590 million years ago)
the first animals were what?
invertebrates
what are the explanations of this increase and animal diversity?
- favorable environments, warm temperature, development of ozone layer
- evolution of Hox genes
- An evolutionary “arms race”
why is the development of ozone layer important?
because the sun is strong to scramble DNA and cause cancer without it
what is an evolutionary “arms race”
as organisms evolve, predators make selection pressures which mean the prey evolves (this goes back and forth for millions of years)
what were the first vertebrates?
fish
what was happening while fish were chilling in the ocean?
plants were colonizing the land