DAT bio chapter 9 Diversity of life Flashcards
taxonomy
science of classifying organisms
Mnemonic for memorizing taxonomy chart
King Phillip Came Over For Great Soup.
6 kingdoms are
Archaea, Eubacteria,
Protista, Fungi, Plantae, Animalia.
3 domains
Archaea, Bacteria (Eubacteria)
and Eukarya.
what is Archaea
are single-celled and tend
to be extremophiles (lives in extreme conditions and temp); they are prokaryotic.
What is bacteria
are also single-celled and prokaryotic.
What is eukarya
classified as having organelles and
membrane-bound nuclei.
What is a prokaryotes
organisms that do not have
membrane bound nuclei and tend to not have
membrane bound organelles.
Example of prokaryotes
Eubacteria and archaea
Difference between gram positives and gram negative
ONly in Bacterai (Eubacteria)
Gram positive bacteria have a thick peptidoglycan
layer in their cell wall, whereas gram negative
bacteria have a thin peptidoglycan layer and a
second outer membrane. Both are covered by a
capsule (a virulence factor protecting the
bacteria from drying out).
Characteristics of gram positive bacteria P1
-stain dark purple. ● thick peptidoglycan layer in cell wall. ● no outer membrane. ● very minor periplasm (outside plasma membrane).
Characteristics of gram positive bacteria P2
● No lipopolysaccharide (LPS - an endotoxin released when bacteria is destroyed). ● Secrete exotoxins. ● Contain teichoic acids (polysaccharide connecting peptidoglycan layer and plasma membrane for rigidity and structure).
Gram negative bacteria
● Stain pink (due to counterstain). ● Thin peptidoglycan layer in cell wall. ● Contains periplasm between inner and outer membranes. ● Outer membrane present. ● LPS present (in outer membrane). ● Secrete exotoxins. ● No teichoic acids.
Similarities between bacteria vs archaea
Contain cell walls. ● 70S ribosomes. ● DNA is organized in circular plasmids (horizontal gene transfer via pilli). ● Flagellum for movement. ● Reproduce via binary fission.
Difference between bacteria vs archaea
Eubacteria - Cell wall contains peptidoglycan; lipids bound via ester-linkage. -Ribosome has unique structure. -DNA lacks introns and histones.
Archaea - Cell wall lacks peptidoglycan; lipids bound via ether-linkage. -Ribosome has unique structure. -Contain introns, some have histones.
what is a eukaryote and give some examples
organisms whose cells contain
membrane-bound nuclei and organelles. E.g.
Protista, Fungi, Plantae, and Animalia.
What is a Protists
kingdom of (mostly unicellular) eukaryotic organisms.
what is a Fungus-like protists:
unlike fungi, no cell wall
made of chitin. Can move via cilia or flagella
(e.g. slime molds). Are saprophytic and feed
via phagocytosis. Reproduce via asexual
reproduction and sporulation (resist
environmental conditions).
Definition of saprophytic:
obtaining food by absorbing dissolved organic material especially : obtaining nourishment from the products of organic breakdown and decay
What is a Plant-like (algae-like) protists:
among the
most important primary producers.
3 types of plant-like protists
Diatoms, and euglenoids are unicellular,
photosynthetic autotrophs that reproduce
asexually and are found in aquatic
environments.
● Dinoflagellates: responsible for red tide
(toxins build up, O2
in water is depleted),
have two flagella (find food in absence of
light), and are heterotrophic (parasitic).
What is a Animal-like protists:
known as protozoa,
have food vacuoles. Include amoeba and
paramecium. Heterotrophic (move via flagella
and cilia) and are often parasitic pathogens.
What is a fungi
heterotrophic (move via flagella
and cilia) saprophytes.
2 types of fungi
nonfilamentous fungi and filamentous fungi
nonfilamentous fungi
(e.g. yeast) are
unicellular, reproduce asexually by budding, and
are facultative anaerobes.
Filamentous fungi
(e.g. molds) are
multicellular, multinucleate (form hyphae),
reproduce sexually, and are aerobic.
What is a hyphae
long, branching filaments that extend
out to form a network of fungi (mycelium).
Mycelium can either grow with septate hyphae
(have septa dividing hyphae into different
sections) or with coenocytic hyphae (one long
continuous multinucleated cell; cytokinesis does
not occur during cell division).
All the hyphae together is called ______
Mycelium
How do fungi reproduce in favorable conditions
reproduce
asexually by producing a haploid spore-producing
structure which produces haploid spores that grow
via mitosis.
How do fungi reproduce in unfavorable conditions
reproduce sexually-producing genetically different
offspring with greater chance of survival. Two
hyphae fuse their cytoplasm (plasmogamy) to
create a single fused cell with 2 haploid pronuclei
which fuse (karyogamy) to produce a single diploid
cell. The diploid cell produces a spore-producing
structure that produces spores via meiosis.
Lichens are ______
symbiotic autotrophs
- fungus is paired with either algae or cyanobacteria.
The fungus protects the cyanobacteria/algae and
provides it with water and nutrients while
algae/cyanobacteria photosynthesize, to produce
food for the fungi.
animalia
Animals are eukaryotic, diploid, multicellular
heterotrophic aerobes.
How can animals be distinguished based on the presence of a coelom (BODY CAVITY) THE SPACE BETWEEN THE BODY WALL AND THE CENTRA GUT AND OTHER INTERNAL ORGANS
In coelomates
mesoderm surrounds the coelom on all sides.
whereas in acoelomates it does not, and in
pseudocoelomates the coelom is partially
surrounded.
Coelomates can be further divided into _____
schizocoelomates (coelom arises from separating
mesodermal cells or enterocoelomates (coelom
formed by outgrowth of primitive gut).
Protostomes tend to be the first type, and
deuterostomes the second.
Porifera
● E.g. Sponge
● Body symmetry: Asymmetrical
● Tissue organization: Parazoa (no true tissues)
● Circulatory system: None (diffusion)
● Nervous system: None
● Respiratory system: None (diffusion)
● Digestive system: Intracellular digestion via
amoebocytes (totipotent cells contribute to
structure, digestion, regeneration, move via
pseudopodia)
General characteristics of porifera
sessile (non-motile),
suspension feeders, aquatic habitats, earliest
animals, reproduce asexually (budding) or sexually
(hermaphrodites - has male and female sex
organs).
What does pseudocoelom (fake coelom) help with
hydroskeleton (fluid pressure providing structural
support) that helps with motility.
Cnidaria:
E.g: hydra, jellyfish, sea anemone, coral.
● Body symmetry: Radial (around central axis).
● Tissue organization: Diploblasts (two cellular
layers: endoderm- and ectoderm), They have no mesoderm..
● Circulatory system: None (diffusion).
● Nervous system: Nerve net (neurons spread
apart), no brain.
● Respiratory system: None (diffusion).
● Digestive system: gastrovascular cavity (one
opening, two way digestion, acts as hydrostatic
skeleton to aid movement).
animal phyla mnenmonic
Privileged Children Play Nicely Rapidly And Maturely, Arthur Ensures Cooperation
General Characteristics for Cnidaria
Aquatic habitats, some
have nematocysts (cells shooting poisonous
barbs), some have life cycles that switch from
polyp (non-motile, reproduce asexually) to medusa
(motile, reproduce sexually) forms
Platyhelminthes:
E.g. Flatworms, trematoda, flukes, tapeworm,
planaria.
● Body symmetry: Bilateral (right and left
halves, axis at sagittal plane) with
cephalization (central nervous system - brain).
● Tissue organization: Triploblasts (three germ
layers), eumetazoa.
● Circulatory system: None (diffusion).
● Nervous system: Two nerve cords (dense
nerve bundle running along length of
invertebrates), anterior centralized ganglia
(brain), some planarians have eyespots.
● Respiratory system: None (diffusion).
● Digestive system: Gastrovascular cavity
(except tapeworms - absorb food).
● Excretory system: Protonephridia (bundles
of flame cells - involved in osmoregulation)
General Characteristics: of platyhelminthes
: reproduce sexually
(hermaphrodites) or asexually (regeneration), mainly
aquatic habitats, parasitic lifestyles, most primitive
of triploblasts, has organs.
What are eumetazoans
animals with true tissue
Nematoda
E.g. Round worm, hook worm, trichinella, C.
elegans, ascaris.
● Body symmetry: Bilateral.
● Tissue organization: Triploblasts, eumetazoa.
● Circulatory system: None (diffusion).
● Nervous system: Nerve cord and ring
(surrounds esophagus).
● Respiratory system: None (diffusion).
● Digestive system: Alimentary canal (passage
between mouth and anus)
General characteristics of nematoda
General Characteristics: Some have cuticle
(prevents degradation by host digestive system),
longitudinal muscles (no circular muscles),
parasitic, not segmented. Primarily reproduce
sexually, but some reproduce asexually through
parthenogenesis
Rotifera:
Body symmetry: Bilateral.
● Tissue organization: Triploblasts, eumetazoa.
● Circulatory system: None (diffusion).
● Nervous system: Cerebral ganglia (brain) with
nerves extending through the body.
● Respiratory system: None (diffusion).
● Digestive system: Alimentary canal, mouth
and anus.
● Excretory system: Protonephridia and flame
cells
General Characteristics: rotifera
Not truly segmented,
can reproduce sexually or parthenogenetically,
mostly freshwater environments. Draw food and
water into mouth by beating cilia.
Annelida:
Ex . Earthworm, leech.
● Body symmetry: Bilateral.
● Tissue organization: Triploblasts, eumetazoa.
● Circulatory system: Closed circulatory
system (blood pumped through vessels by
heart), multiple pairs of aortic arches, distinct
arteries and veins.
● Nervous system: Ventral nerve cord, anterior
ganglia (brain).
● Respiratory system: None (diffusion).
● Digestive system: Alimentary canal, mouth
and anus.
● Excretory system: Most have metanephridia
(excretory glands for osmoregulation. Tubes of
cilia move fluid emptying into coelom, ducts
bring fluid to the exterior).
● Embryonic development: Protostome
(blastopore forms mouth).
General characteristics of annelida
Segmented bodies, coelom is divided by septa, sexual (hermaphrodites) and asexual (regeneration) reproduction, longitudinal and circular muscles.
Mollusca:
E.g. Clam, snail, slug, squid, octopus,
cephalopod, gastropod.
● Body symmetry: Bilateral.
● Tissue organization: Triploblasts, eumetazoa.
● Circulatory system: Mainly open; hemocoel
(spaces inside an organism where blood freely
flows around organs).
● Nervous system: Ventral nerve cords and
brain.
● Respiratory system: Gills.
● Digestive system: Complete (alimentary
canal and accessory glands), mouth and anus,
radula (tongues covered in tiny teeth - unique
to mollusks).
● Excretory system: Nephridia (pairs of
osmoregulatory ‘kidneys’ in invertebrates).
● Embryonic development: Protostome
Arthropoda (all):
Body symmetry: Bilateral.
● Tissue organization: Triploblasts, eumetazoa.
● Circulatory system: open, hemolymph
(equivalent to blood).
● Nervous system: Fused ganglia (masses of
nerve tissue), ventral nerve cord.
● Digestive system: one-way digestion, some
have salivary glands.
● Embryonic development: Protostome
Arthropoda (Insecta):
E.g. ant, grasshopper. ● Respiratory system: Spiracles (small openings on exoskeleton where air enters) branch into tracheal tubes (site of gas exchange). ● Excretory system: Malpighian tubules (small tubes on abdomen, help with uric acid excretion)
General Characteristics of insecta
Exoskeleton of chitin, jointed appendages, three pairs of legs, more species than any other phylum combined, metamorphosis (distinct stages, altered appearance as insect matures).
Arthropoda (Arachnida):
E.g. spider, scorpion. ● Respiratory system: trachea or book lungs (sheets of vascularized tissue on either side to increase surface area). ● Excretory system: Malpighian tubules and / or coxal gland
General characteristics of arachinidia
Exoskeleton, jointed
appendages, four pairs of legs, terrestrial habitats
Arthropoda (Crustacea):
E.g. lobster, crayfish, crab.
● Respiratory system: some have gills.
● Excretory system: Green glands (aquatic),
malpighian tubules (terrestrial).
General Characteristics: crustatcea
: Exoskeleton, jointed
appendages, aquatic and terrestrial habitats.
Echinodermata:
E.g. Starfish, sea urchin, sea cucumber. ● Body symmetry: Bilateral (larvae), five fold radial (adult). ● Tissue Organization: Triploblasts, eumetazoa. ● Circulatory system: open, no heart. ● Nervous System: Nerve ring and radial nerves. ● Respiratory system: None (diffusion). ● Digestive system: Complete, mouth and anus. ● Excretory system: None (diffusion). ● Embryonic Development: Deuterostome (blastopore forms anus)
General characteristics for echinodermata
Spiny, central disk
(central portion from which arms radiate, contains
mouth, anus and opening for water to enter for
water vascular system), tube feet (suction cups for
walking and obtaining food), sexual or asexual
reproduction, closest related major phyla to
chordates.
Chordates (Most important for DAT):
E.g. Vertebrates.
● Body Symmetry: Bilateral.
● Tissue Organization: Triploblasts, eumetazoa.
● Embryonic Development: Deuterostome.
Shared Traits of all Chordates:
Notochord
Dorsal hollow nerve cord
pharyngeal gill slits
muscular post anal tail
Notochord
cartilaginous rod derived from mesoderm. Forms the primitive axis and supports the body during embryonic development. Lost in most chordates, and replaced by bone
Dorsal Hollow Nerve Cord:
: forms spinal cord -
basis of nervous system and brain.
Pharyngeal Gill Slits:
: forms pharynx, gills,
other feeding structures. Provide channels
from pharynx to other structures. In humans
forms Eustachian tubes and other head and
neck structures
Muscular post-anal tail :
lost during
embryonic development in humans and many
other chordates.
Lancelets (also known as Amphioxus): Chordates
Subphylum: Cephalochordata. ● Circulatory system: Closed circulatory system, lacks heart, contains contractile blood vessels. ● Respiratory system: Gills. ● General characteristics: Keep all the same developmental characteristics as other chordates, but lack vertebrae. Commonly used to study the origin of vertebrates
Tunicates (also known as Urochordata): Chordates
Subphylum: Tunicata. ● Circulatory system: Both closed and open circulatory systems. ● Respiratory system: Gills. ● General characteristics: Sessile, filter feeders, hermaphroditic, sexual and asexual (budding) reproduction. Benthic habitats (bottom of a body of water), notochord in larvae.
Fish (Jawless): chordates
E.g. Agnatha, lamprey, hagfish. ● Subphylum: Vertebrata. ● Circulatory system: Two-chambered heart. ● Respiratory system: Gills, countercurrent exchange. ● General characteristics: Notochord in larvae and adult, cartilaginous skeleton
Fish (Cartilaginous): chordates
E.g. Shark. ● Subphylum: Vertebrata. ● Circulatory system: Two-chambered heart. ● Respiratory system: Gills. ● General characteristics: Jaws and teeth, reduced notochord with cartilaginous vertebrae
Fish (Bony): chordates
E.g. Salmon, halibut. ● Subphylum: Vertebrata. ● Circulatory system: Two-chambered heart. ● Respiratory system: Gills. ● General characteristics: scales, bony skeleton.
Amphibia: chordates
E.g. Frog, toad, salamander, newt ● Subphylum: Vertebrata ● Circulatory system: Three-chambered heart. ● Respiratory system: Gills (juvenile), Lungs (adult). ● General characteristics: No scales. Undergo metamorphosis. Tadpoles (aquatic) have tails, no legs. Adults (terrestrial) two pairs of legs, no tail
Mammalia (Monotremes): chordates
E.g. Duckbill platypus, spiny anteater. ● Subphylum: Vertebrata. ● Circulatory system: Four-chambered heart. ● Respiratory system: Lungs. ● General characteristics: Warm blooded (homeothermic), feed young with milk, leathery eggs, mammary glands with many openings (no nipples)
Mammalia (Marsupials): chordates
E.g. Kangaroo, opossum. ● Subphylum: Vertebrata. ● Circulatory system: Four-chambered heart. ● Respiratory system: Lungs. ● General characteristics: Homeotherms, feed young with milk.
Mammalia (Placental): chordates
E.g. Bat, whale, mouse, human. ● Subphylum: Vertebrata. ● Circulatory system: Four-chambered heart. ● Respiratory system: Lungs. ● General characteristics: homeotherms, placenta supports fetus
Reptilia: chordates
E.g. Turtle, snake, crocodile, alligator. ● Subphylum: Vertebrata. ● Circulatory system: Three-chambered heart (exception: crocodiles and alligators = four-chambered heart). ● Respiratory system: Lungs. ● General characteristics: Mainly terrestrial, leathery eggs, internal fertilization, cold blooded (poikilothermic)
Birds: chordates
● E.g. Eagle, blue jay. ● Subphylum: Vertebrata. ● Circulatory system: Four-chambered heart. ● Respiratory system: Lungs. ● General characteristics: homeotherms, eggs in shells.
