Biology Exam 1 Flashcards
Define biology
the study of life
What do all life forms share?
DNA, cells, evolutionary forces
What are the 8 organisms classified in?
Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
Define Zoology
the study of animals
Are sponges animals?
yes!
U.S. Endangered Species Act
1973, protects animals in danger of extinction
Define endangered species
imminent danger of extinction throughout its range
Define threatened species
likely to become endangered in the future
Define radial symmetry
any plane passing through the central axis divides the animal into mirror images
Define bilateral symmetry
only 1 plane passing lengthwise along the central axis creates a mirror image
Define diploblastic
body parts organized into layers derived from 2 embryonic tissues
Blind-sac body plan is?
body layout in which the mouth is the only permanent opening
What is triploblastic?
tissues derived from 3 embryological layers
Define triploblastic acoelomate
tissues derived from mesoderm, solid mass of cells, with no true body cavity
Define triploblastic pseudocoelomate
body cavity is not entirely lined by mesoderm, false body cavity
Define triploblastic coelomate
body cavity completely surrounded by mesoderm, true body cavity
What separates protostomes from deuterostomes?
protostomes have spiral and determinate cleavage, while deuterostomes have radial and inter determinate cleavage
Define determinate cleavage
each cell in the blastula will become something, which was determined very early in the cell’s life
Define intermediate cleavage
fate of each cell is determined much later in the cells life
What category of protostomes molt, and which do not?
Ecdysozoan animals molt, Lophotrochozoan animals don’t
How are protostomes categorized, and how have they been previously?
Used to be type of coelom, now is molting or not
Define organic evolution
organisms change over time due to selective forces
Describe Jean Baptiste Lamarck’s theory
Theory of inheritance and acquired characteristics says that species are not constant and existing species are derived from pre-existing species
Define allopatric speciation
occurs when populations are separated by geographical barriers
Define sympatric speciation
gradual differences or other factors lead to a new species
Define Phyletic Gradualism
evolutionary change is gradual, slow, and constant
Define punctuated equilibrium
evolution occurs rapidly followed by stability with little change
Describe protozoa
domain eukarya, polyphyletic, includes animals, plants, and fungi, unicellular
Define ectoplasm
thick, clear, and firm
What is endoplasm?
granular fluid
Define cytopharynx
specialized region similar to a mouth
How to protozoa move?
flagellum, cilia, or pseudopodia
How do protozoa reproduce?
Asexual- binary fission
Sexual- zygotic meiosis
Define conjugation
mutual exchange of micronuclei in a complex meiosis/mitosis process
Describe Phylum Porifera
Sponges, aquatic (marine), 9000 species, asymmetrical, no true tissues
What are the 3 forms of sponges?
Ascon (least complex), sycon, leucon (most complex)
How do sponges reproduce?
they are monoecious, so they can release sperm and egg cells, some can also do asexual from fragmentation, regeneration, and gemmules
Describe phylum cnidaria
jellyfish, hydra, anemones, and corals, 9000 species, marine, radial or biradial, can be poisonous
Define aposematism
dangerous or noxious organisms advertise to potential predators (like bright colored frogs)
Gastrovascular cavity
blind sac body plan, cavity with a single opening, basically a mouth and anus
Define cnidocytes
used for defense, feeding, and attachment, not all sting
Nematocysts
discharge tubes armed with spines and toxins or sticky structure to pull in prey
Cnidaria body forms are:
polyp- asexual and sessile
medusa- dioecious and free-swimming, tentacles go down
Define hydrostatic skeletion
water-filled cavity gives body shape and support
Triploblastic classification
protostomes, primitive
deuterostomes, advanced
Name the 5 phyla
acoelomorpha, Platyhelminthes, Nemertea, gastrotrichs, and cycliophora
Describe Acoelomorpha
small, flattened, marine worms, fee-living, asexual and monoecious
Describe flatworms
flattened, unsegmented, organ systems, blind body sac
Describe turbellariia
Planarians, 3000 species, eye spots, free-living, osmoregulation, flame cells
Monogenea
1000 species, aquatic, ectoparasites of fish
Trematoba
10000 species, parasitic, attach with 2 suckers
Tapeworms
3500 species, highly specialized, absorb nutrients through body wall
Nemertea
Proboscis or ribbon worms, 900 species, free-living, marine, complete digestive tract, dioecious
What is the importance of surface area?
more surface area = more efficient filtration and processing
Describe gastrotrichs
cilia, forked tail, 500 aquatic species, acoelomate, monoecious, no larval stage
Cycliophora
symbions, most recently described phylum, mouth of lobsters
