taxonomy
- a system by which we name and classify all organisms, living and extinct
-based on system developed in 18th century by Carl Linnaeus
-based on anatomical structures / embryology
binomial nomenclature
- the system of taxonomy which gives every organism a two part name
-name = genus species
-ex/ Homo sapiens
taxa
levels of organization in taxonomy; (DKPCLOFGS)
domain
kingdom
phylum
class
order
family
genus
species
extremophiles
- microorganisms that live in extreme environments that seem very different from bacteria and so have been placed in a separate kingdom = Archaea
three-domain system
a taxonomic system based on DNA analysis
domains
the three main groups of classification; bacteria
archaea
eukarya
domain Bacteria
-all single celled prokaryotes (no internal membranes / organelles)
-some are aerobic and some are anaerobic
-some are autotrophs, others are heterotrophs
- some are decomposers
-some are pathogens
-play vital role in genetic engineering
- carry out conju
prokaryotes
cells with no internal membranes; no nucleus, mitochondria, or chloroplasts
decomposers
recycle dead organic matter
pathogen
causes disease
conjugation
a primitive form of sexual reproduction where bacteria exchange genetic material
domain Archaea
-unicellular
-prokaryotic
-includes extremophiles: methanogens, halophiles, and thermophiles
-introns are present in some genes
methanogens
obtain energy by producing methane from hydrogen
halophiles
thrive in environments with high salt concentration (Utah's Great Salt Lake)
thermophiles
thrive in very high temperatures (hot springs Yellow Stone park; deep sea hydrothermal vents)
domain Eukarya
-all organisms have a nucleus and internal organelles
-include the remaining four kingdoms: protista, fungi, plantae, and animalia
kingdom Protista
-all are eukaryotes
-most single-celled
-includes heterotrophs and autotrophs
---examples of heterotrophs = AMOEBA, PARAMECIUM
---example of autotroph = EUGLENA, which have a red spot to locate light and chlorophyll to carry out photosynthesis
move by var
kingdom Fungi
-all are heterotrophic eukaryotes
-unicellular or multicellular
-carry out extracellular digestion
-are decomposers
- cell walls are made of chitin
-reproduce asexually by budding (yeast), spore formation (bread mold), or fragmentation (where a single par
extracellular digestion
-when organisms secrete hydrolytic enzymes outside the body
-after digestion, the building blocks of nutrients are absorbed into the body by diffusion
saprobes
organisms that obtain food from decaying organic matter
chitin
makes up the cell wall of fungi
pioneer organism
-the first organism to colonize a barren environment (primary succession)
-often bacteria and lichens
kingdom Plantae
-multicellular nonmotile autotrophic eukaryotes
-cell walls are made of cellulose
-carry out photosynthesis
-store carbohydrates as starch
-reproduce sexually by alternating between gametophyte (n) and sporophyte (2n) generations = alternation of generati
kingdom Animalia
-heterotrophic multicellular eukaryotes
-most are motile and reproduce sexually, with dominant diploid (2n) stage
- small flagellated sperm fertilizes a larger nonmotile egg
-35 phyla, but know 9: porifera, cnidarians, platyhelminthes, nematodes, annelids
Cnidaria
-animal phylum
-hydra or jellyfish
-radial symmetry
-body plan is POLYP (vase shaped, which is mostly sessile or MEDUSA (upside-down bowl shape that is mostly motile
-life cycle: some go through PLANULA LARVA (free-swimming) stage, then two reproductive s
germ layers
-main layers that form various tissues and organs of the body
-formed early in embryonic development
-include the ectoderm, endoderm, and mesoderm
ectoderm
-the outermost germ layer
-becomes the skin and nervous system (including nerve cord and brain)
endoderm
-the innermost germ layer
-becomes the digestive system
mesoderm
-the middle layer
-becomes blood, muscles, and bones
mesoglea
-middle glue that holds ectoderm and endoderm together in some animals (sponges; cnidarians)
triploblastic
-having all three germ layers, the endoderm, ectoderm, and mesoderm
radial symmetry
-the symmetry of more primitive animals
-arrangement of body parts like pieces of pie around an imaginary central axis
-any slice passing longitudinally through central axis divides the organism into mirror-image halves
bilateral symmetry
-the symmetry of more sophisticated animals
(except echinoderms which are complex animals with bilateral symmetry as larva and radial symmetry as adults)
- the body is organized along a longitudinal axis with right and left sides that mirror each other
cephalization
-development of a head -- seen in more sophisticated complex animals
-has anterior and posterior ends
-sensory apparatus and brain / ganglia are located at anterior end; digestive, excretory, and reproductive structures are at posterior end
coelom
-fluid filled body cavity that is completely surrounded by mesoderm tissue
-is a significant advance in course of animal evolution because it provides space for elaborate organ systems like digestive tract or cardiovascular system
acoelomates
-animals without a coelom
-bodies tend to be flat and all cells are in direct contact with watery environments
-ex/ flatworms
pseudocoelomates
-have fluid filled tubes between the endoderm and the mesoderm that act as a hydrostatic skeleton to support the animal
-ex/nematodes and roundworms
hydrostatic skeleton
a system of fluid filled tubes that supports an animal
coelomates
-animals with a coelom (fluid-filled body cavity)
-are most advanced in the kingdom
-include Annelida, Mollusca, Arthropoda, and Chordata
Porifera
- animal phylum
- sponges
-loose federation of cells, which are NOT considered tissue since cells are relatively unspecialized (each cell carries out many functions)
-two cell layers - ectoderm and endoderm connected by noncellular mesoglea
- have no symm
fragmentation
a type of asexual reproduction where parents break apart and each daughter organism grows from those particles
sessile
nonmoving
polyp
vase shaped cnidarian, sessile
medusa
upside down bowl shaped cnidarian, motile
motile
moving
cnidocytes
stinging cells in cnidarians
nematocysts
stingers in cnidarians
Platyhelminthes
-animal phylum
-flatworms and tapeworms
-simplest animals with bilateral symmetry and three cell layers (endoderm, mesoderm, ectoderm)
- have solid body (acoelemate) and no room for true digestive or respiratory systems
-body is flat and thin so that body
Nematodes
-animal phylum
-round worms
-pseudocoelomate
-unsegmented with bilateral symmetry; many are parasitic
Annelids
-an animal phylum
-segmented worms like earthworms and leeches
-coelmate
-bilateral symmetry
-digestive tract - tube eithin tube consisting of crop, gizzard, intestine
-nephridia for excretion of waste - urea
-closed circulatory system - heart has 5 pairs
Mollusks
-animal phylum
-squids, octopuses, slugs, clams, and snails
-coelmate
-have soft body often protected by hard shell
-open circulatory system
-have bilateral symmetry with three distinct body zones
1) head-foot - with sensory and motor organs
2) visceral m
head foot
contains both sensory and motor organs
visceral mass
contains organs of digestion, excretion, and reproduction
mantle
specialized tissue that surrounds the visceral mass and secretes that shell
radula
movable tooth bearing structure that acts like a tongue
Arthropoda
-is an animal phylum
-has insects (grasshoppers); crustacea (shrimp, crab), arachnida (spider)
-jointed appendages
-segmented into head, thorax, and abdomen
-chitinous exoskeleton
-open circulatory system with tubular heart
-Malpighian tubules for removal
Crustacea
-in arthropod phylum
-shrimp, crab
-jointed appendages
-segmented into head, thorax, and abdomen
-chitinous exoskeleton
-open circulatory system with tubular heart
-Malpighian tubules for removal of waste - uric acid
-air ducts called trachea
arachnida
-in arthopod phylum
-spiders
-jointed appendages
-segmented into head, thorax, and abdomen
-chitinous exoskeleton
-open circulatory system with tubular heart
-Malpighian tubules for removal of waste - uric acid
-air ducts called trachea
Echinoderms
-in animal kingdom
-sea stars and sea urchins
-sessile or slow moving
-have bilateral symmetry as embryo but revert to radial symmetry as an adult
-water vascular system creates hydrostatic support for tube feet - their locomotive structures
-reproduce se
chordates
-in animal kingdom (a phylum)
-fish, amphibians, reptiles, birds, mammals
-have notochord
have hollow nerve chord
-tail aids in movement and balance
-birds and mammals are homoetherms (constant body temperature)
-fish, amphibians, and reptiles are endothe
notochord
-cartilaginous skeletal rod supporting the body in all embryonic and some adult chordate animals
homeotherm
maintain consistent body temperature
endotherms
can heat from within and are able to raise their body temperatures
mammals
-belong to the phylum chordata
-nourish young with milk
-have hair or fur
-endotherms
-most are placental (eutherians)
marsupials
-mammals where the embryo is born very early and completes its development in a pouch
monotreme
-egg laying mammals
-duck-billed platypus and spiny anteater
primates
-descended from insectivores - small tree dwelling mammals
-opposable thumbs
-nails instead of claws
-forward facing, close set eyes
-single births; most intense parenting of any mammal
cladogram (phylogenetic tree)
-a diagram that represents evolutionary history based on DNA sequences
-build based on shared and derived traits
shared traits
traits organisms have in common
derived traits
new characteristics that are not shared with ancestors
images - protists
lichen
certain fungi combine with algae in a mutualistic symbiotic relationship -- and because of algae are phtosynthetic
alternation of generation
-life cycle in which there is a multicellular diploid (2n) = the SPOROPHYTE; and a multicellular haploid form (n) = GAMETOPHYTE
-characteristic of plants and multicellular green algae
image alternation of generation
evolutionary trends in animals
-first multicellular eukaryote evolved about 1.5 billion years ago
-appearance of each phylum of animal represents evolution of new and successful body plan:
-trends =
1) specialization of tissues (cell, tissue, organ)
2) germ layers (ectoderm, mesoderm,
image - trends in animal development
animals with only two cell layers
porifera and cniderians
image of symmetry in animals
image of body cavities
image mollusks
grasshopper image
- phylum arthropoda