Classification Flashcards
Taxa
Kingdom, Phylum, Class, Order, Family, Genus, Species
The Five Kingdoms
Monera, Protista, Fungi, Plantae, and Animalia (sometimes Archaebacteria)
Three-Domain System
Bacteria, Archaea, Eukarya
Bacteria Domain Comparison
No membrane enclosed organelles; Peptidoglycan in the cell wall; One type of RNA polymerase; Introns are absent; Antibiotic sensitivity to streptomycin ad chloramphenicol inhibited
Archaea Domain Comparison
No membrane enclosed organelles; Peptidoglycan absent in the cell wall; Several kinds of RNA polymerase; Introns are present in some genes; Antibiotic sensitivity to streptomycin and chloramphenicol are not inhibited
Eukarya Domain Comparison
Membrane enclosed organelles; Peptidoglycan absent in the cell wall; Several kinds of RNA polymerase; Introns are present; Antibiotic sensitivity to streptomycin and chloramphenicol are not inhibited
Domain Bacteria
Some are anaerobes/aerobes; decomposers; pathogens; used in genetic engineering; carry out conjugation; photosynthetic/not photosynthetic; viruses included
Domain Archaea
Unicellular; includes extremophiles
Conjugation
primitive form of sexual reproduction where individuals exchange genetic material
Extremophiles
Include methanogens which obtain energy by producing methane from hydrogen. Halophiles thrive in areas with high salt concentrations. Thermophiles thrive in very high temperatures.
Domain Eukarya
Includes Protista, Fungi, Plantae, and Animalia
Kingdom Protista
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Kingdom Fungi
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Kingdom Plantae
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Kingdom Animalia
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Evolutionary Trends in Animals
Organisms begin as tiny, primitive, single-celled organisms in oceans. Then, about 1.5 billion years ago multicellular eukaryotic organisms evolved. Trends include: specialization of tissues, germ layers, body symmetry, cephalization and body cavity formation.
Primitive Developmental Features
- No symmetry/radial symmetry with little to no sensory apparatus
- Two cell layers: ectoderm and endoderm
- No Coelom
- No true tissue
- Life in water
- Sessile
- Few Organs/No organ systems
Complex Developmental Features
- Bilateral symmetry with a head end and complex sensory apparatus
- Cephalization
- Triploblastic: ectoderm, mesoderm and endoderm
- Pseudocoelom to coelom
- True tissues, organs and organ systems
- Life on land and all the modification it requires
- Motile
Cell
basic unit of all forms of life (ex. Nueron)
Tissue
groups of cells that perform a particular function (Sciatic Nerve)
Organ
group of tissues that work together to perform related functions
Germ Layer
the three main layers of the body that form various tissues and organs of the body; formed through gastrulation
Ectoderm
outermost germ layer; becomes the skin and nervous system; includes the brain and spinal cord
Endoderm
innermost germ layer; becomes the viscera (guts) or the digestive system
Mesoderm
middle germ layer; becomes the blood and bones
Two Germ Layers
diploblastic; Porifera and Cnidarians only have the ectoderm and endoderm with the mesoglea to connect the two
Bilateral Symmetry
the body is organized along a longitudinal axis with the right and left sides that mirror each other; echinoderms are an exception because they have bilateral symmetry as larvae and convert to radial symmetry as adults; bilateral animals are usually triploblastic
Cephalization/Development of the Head End
With bilateral symmetry comes and anterior (front) end and a posterior (back) end; Sensory apparatus and brains are located in the anterior while digestive, excretory and reproductive organs are located in the posterior
Coelom
fluid filled body cavity; arises from within the mesoderm and is surrounded by mesoderm tissue; provides space for transport and respiratory systems
Acoelomates
Porifera, Cnidaria, and Platyhelminthes which have no coelom; their three germ layers are packed with no body cavity except the digestive one
Pseudocoelomates
Nematodes or roundworms have a fluid filled tube between the endoderm and the mesoderm; Acts as a hydrostatic skeleton and increases effectiveness of an animal’s muscular contractions
Protostomes
Division of coelomates in which the first opening, called the blastopore, becomes the mouth. Include annelids, mollusks and arthropods.
Deuterostomes
Division of coelomates in which the second opening becomes the mouth and the first opening becomes the anus. Include echinoderms and chordates.
Porifera - The Sponges - Invertebrates
- No nerves, muscles, symmetry or movement.
- Spongocoel is a central cavity that filters water drawn to it.
- Diploblastic
- Only three types of cells: choanocytes, spicules, and amoebocytes.
- Evolved from colonial organisms.
- Reproduce sexually and through sexually as they are hermaphrodites.
Porifera: Choanocytes
collar cells that line the body cavity and have flagella that circulate water
Porifera: Spicules
supportive and classification is done by the type of spicule
Porifera: Amoebocytes
cells that move on their own and perform functions such as reproduction, carrying food particles to non-feeding cells and secretion of material that forms the spicules
Cnidarians - Hydra and Jellyfish
- Invertebrates with radial symmetry.
- Polyp (vase) shaped or medusa (upside down bowl) shaped.
- Diploblastic
- The gastrovascular cavity it where extracellular digestion occurs.
- Intracellular digestion is carried out by lysosomes.
- Have no transport systems
- Contain stinging cells called cnidocytes.
Life Cycle of Cnidarians
Some go through a planula larva stage then go through two reproductive stages: asexually reproducing poly stage and a sexually reproducing medusa stage
Platyhelminthes - Flatworms + Tapeworms
- Invertebrates that are the simplest animals with bilateral symmetry, anterior end, three cell layers, and cephalization.
- Have true tissues and organs.
- Digestive tract has one opening for digestion and excretion so they do not occur at the same time.
- Acoelomates: have a flat body to keep cells in contact with oxygen and a branched digestive cavity to spread nutrients
Nematoda - Roundworms
- Unsegmented invertebrates with bilateral symmetry and litter sensory apparatus.
- Protostome pseudocoelmates
- Pseudocoelom transports nutrients with little room for a circulatory system.
- Parasitic - Trichinosis
Annelida - Segmented Worms: Earthworms/Leeches
- Invertebrate, Protostome coelomates with bilateral symmetry yet little sensory apparatus
- Digestive tract is a tube within a tube consisting of a crop, gizzard and intestine
- Nephridia used for excretion of nitrogenous waste and urea
- Closed circulatory system with a five aortic arch heart
- Hemoglobin in blood
- Diffusion of O and CO2
- Hermaphroditic but no self fertilization
Mollusca - Squids, Octopuses, Slugs, Clams and Snails
- Invertebrate, Protostome coelomates
- Soft body with hard, calcium-containing shell
- Bilateral symmetry
- Radula, movable tooth-bearing structure, acts as a tongue
- Open circulatory system with blood-filled spaces called hemocoels, lack capillaries
- Gills and Nephridia
Body Zones of Mollusca
In the head-foot zone, it contains sensory and motor organs. In the visceral mass it contains the organs of digestion, excretion and reproduction. The Mantle zone is a specialized tissue that surrounds the visceral mass and secretes the shell.
Arthropoda - Insects (grasshoppers), Crustaceans (shrimp, crabs), and Arachnids (spiders)
- Invertebrates, Protostome coelomates with jointed appendages and segmented head, thorax and abdomen
- Have more sensory apparatus than annelids which give them more speed and movement
- Chitinous exoskeleton protects and aids in movement
- Open circulatory system with a tubular heat and hemocoel, lack capillaries
- Malpighian tubules remove nitrogenous wastes and uric acid
- Aird ducts bring air from trachea into hemocoels
- Book lungs/ book gills
Echinodermata - Sea Stars (starfish) and Sea Urchins
- Invertebrate, Deuterostome coelomates that are sessile/ slow
- Bilateral as embryo and radial as an adult (adaptation for sessile lifestyle)
- Water vascular system (modified coelom) created hydrostatic pressure for tube feet (the locomotive structures)
- Sexual reproduction with external fertilization
- Fragmentation and regeneration
- endoskeleton with calcium plates that grow into the body
Chordata - Fishes, Amphibians, reptiles, Birds and Mammals
- Vertebrate, deuterostome coelomates with a notochord that extends the length of the body and serves as a flexible axis
- Dorsal with hollow nerve cord
- Tails that aid in movement and balance (coccyx bones in humans)
- Birds and mammals are endotherms and homeotherms while others are ectotherms
Endotherm/Homeotherm
maintain a consistent body temperature
Mammals
- Keratin in hair/fur
- Mother provides milk
- Homeotherms
Placental Mammals
Eutherians’ born and the embryo develops internally in a uterus connected to the mother by placenta where nutrients diffuse from mother to embryo
Marsupials
Mammals; Kangaroos; born early in embryonic development and the joey completes its development while nursing in the mother’s pouch
Monotremes
egg-laying mammals; platypus and anteater; derive nutrients from a shelled egg
Primates
- Descended from insectivores
- Dexterous hands (sensitive/nerve endings) with opposable hands
- Claws replaced by nails
- Front -facing eyes enhance communication
- Parents young (nurture their young for a long time)
- humans, gorillas, chimpanzees, orangutans, gibbons etc.
