Diversity of Life Flashcards
(63 cards)
1
Q
Name the 6 Kingdoms
A
1) Archaea
2) Eubacteria
3) Protista
4) Fungi
5) Plantae
6) Animalia
2
Q
A domain is the ______ classification of life; the
three domains are Archaea, Bacteria (Eubacteria)
and Eukarya. _____ are single-celled and tend
to be extremophiles; they are __________.
_____ are also single-celled and prokaryotic.
______ are classified as having organelles and
membrane-bound nuclei.
A
1) largest
2) Archaea
3) prokaryotic
4) bacteria
5) Eukarya
3
Q
In the past, bacteria and archaea were grouped in
one kingdom, known as _____ due to both
groups’ lack of membrane-bound organelles.
A
2) monera
4
Q
Prokaryotes
A
- organisms that do not have
membrane bound nuclei and tend to not have
membrane bound organelles. E.g. Eubacteria and
Archaea.
5
Q
Bacteria are classified based on their shape and growth pattern:
A
● Coccus - spherical shaped
● Spirochete - spiral shaped
● Bacillus - rod shaped
● Strep - grows in a chain
● Staph - grows in grape-like clusters
● Diplo - grows in pairs
6
Q
Some bacteria can produce an _______, a
non-reproductive structure that preserves the
cell’s genetic material, allowing the cell to survive
during times of ______.
A
1) endospore
2) extreme stress
7
Q
Eubacteria:
A
1) Gram +
2) Gram -
8
Q
Gram positive bacteria
A
- have a thick peptidoglycan
layer in their cell wall. Both are covered by a
capsule (a virulence factor protecting the
bacteria from drying out).
Gram Positive Bacteria:
● Stain dark purple.
● Thick peptidoglycan layer in the cell wall.
● No outer membrane.
● Very minor periplasm (outside plasma
membrane).
● No lipopolysaccharide (LPS)
● Secrete exotoxins.
● Contain teichoic acids (polysaccharide
connecting peptidoglycan layer and plasma
membrane for rigidity and structure).
Mnemonic: LONG
L = Lipopolysaccharide
O = Outer membrane
N = Negative
G = Gram
9
Q
Gram -
A
- whereas gram negative
bacteria have a thin peptidoglycan layer and a
second outer membrane. Both (Gram +/-) are covered by a capsule (a virulence factor protecting the
bacteria from drying out).
Gram Negative Bacteria:
● Stain pink (due to counterstain).
● Thin peptidoglycan layer in the cell wall.
● Contains periplasm between inner and outer
membranes.
● Outer membrane present.
● LPS present (LPS - an endotoxin released
when bacteria is destroyed).
● Secrete exotoxins.
● No teichoic acids.
Mnemonic: PPT
P = Positive
P = Peptidoglycan
T = Teichoic acid
10
Q
Eubacteria vs Archaea
A
Similarities:
● Contain cell walls.
● 70S ribosomes.
● DNA is organized in circular plasmids
(horizontal gene transfer via pilli).
● Flagellum for movement.
● Reproduce via binary fission.
Differences:
Eubacteria - Cell wall contains peptidoglycan; lipids bound via ester-linkage; DNA lacks introns and
histones.
Archaea - Cell wall lacks peptidoglycan; lipids bound via ether-linkage; Contains introns, some have
histones.
11
Q
________: organisms whose cells contain
membrane-bound nuclei and organelles.
A
1) Eukaryotes
12
Q
______: kingdom of (mostly unicellular)
eukaryotic organisms.
A
- Protists
13
Q
Fungus-like protists
A
- 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).
14
Q
Plant-like (algae-like) protists
A
- among the most important primary producers. Algae
encompasses a large variety of plant-like protists due to having chloroplasts and
photosynthetic ability.
15
Q
Diatoms and euglenoids
A
- are unicellular, photosynthetic autotrophs that reproduce asexually and are found in aquatic
environments.
16
Q
Dinoflagellates
A
- 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).
17
Q
Animal-like protists
A
- known as protozoa,
have food vacuoles. Include amoeba and paramecium. Heterotrophic (move via flagella and cilia) and are often parasitic pathogens.
18
Q
______ are heterotrophic saprophytes that have a
predominantly haploid life cycle.
A
- Fungi
19
Q
Nonfilamentous fungi
A
- (e.g. yeast) are
unicellular, reproduce asexually by budding, and
are facultative anaerobes.
20
Q
Filamentous fungi (e.g. molds)
A
- are multicellular, multinucleate (form hyphae),
reproduce sexually, and are aerobic.
21
Q
Hyphae
A
- are long, branching filaments that extend
out to form a network of fungi (mycelium).
22
Q
Mycelium
A
-network of fungi; 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).
23
Q
Under ______, fungi reproduce ______ by producing a conidia, a ______
spore-producing structure which produces haploid
spores that grow via _____. Additionally, fungi
have the ability to reproduce via ______.
A
1) favorable conditions
2) asexually
3) haploid
4) mitosis
5) regeneration
24
Q
In __________, fungi reproduce
______-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 (______) to produce a single diploid cell. The diploid cell produces a _________that produces spores via meiosis.
A
1) unfavorable conditions
2) sexually
3) karyogamy
4) spore-producing structures
25
Lichens
- are symbiotic autotrophs where a 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.
26
______ are eukaryotic, diploid, multicellular
heterotrophic aerobes.
- animals
27
Animals can be distinguished based on the
presence of a _____ (cavity). In coelomates, _____ surrounds the coelom on all sides. Whereas in _____ it does not, and in _______ the coelom is partially
surrounded. The pseudocoelom is a
_______ (fluid pressure providing structural
support) that helps with motility.
1) coelom
2) mesoderm
3) acoelomates
4) pseudocoelomates
5) hydroskeleton
28
Coelomates can be further divided into:
1) Schizocoelomates
2) Entercoelomates
29
schizocoelomates
- (coelom forms through
separation of mesodermal cells)
30
enterocoelomates
-(coelom forms through the
out-pocketing of the embryonic gut into the
mesodermal space).
31
______ are usually
schizocoelomates, however, some _______
can also exhibit schizocoely.
1) protostomes (holoblastic, spiral, determinant cleavage)
2) deuterostomes (radial, indeterminate)
32
In ______, the coelom begins as splits
within the mesoderm. In _________, the coelom begins as lateral out-pockets of the archenteron.
1) schizocoelomates
2) enterocoelomates
33
Some organisms exhibit ________ (sperm fertilizing egg within the female’s body), while others exhibit __________ (sperm
fertilizing egg outside the female’s body). Animals
that do internal fertilization have more ______, ________, and produce ________.
1) internal fertilization
2) external fertilization
3) complex anatomies
4) higher rates of reproductive success
5) fewer gametes
34
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
General characteristics: sessile (non-motile),
suspension feeders, aquatic habitats, earliest
animals, reproduce asexually (budding) or sexually
(hermaphrodites - has male and female sex
organs), spicule (skeletal needle) present.
35
Cnidaria
● E.g: hydra, jellyfish, sea anemone, coral.
● Body symmetry: Radial (around central axis).
● Tissue organization: Diploblasts (two cellular
layers: endo- and ectoderm), true tissues
(eumetazoa).
● 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).
General Characteristics: Aquatic habitats, some
have cnidocytes (cells shooting poisonous barbs),
some have life cycles with a polyp stage (non-motile, majority reproduce asexually but some sexually).
36
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).
● Embryonic development: Protostome
(blastopore forms mouth).
General Characteristics: reproduce sexually
(hermaphrodites) or asexually (regeneration), mainly
aquatic habitats, parasitic lifestyles, most primitive
of triploblasts, has organs.
37
Nematoda
● E.g. Roundworm, hookworm, 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).
● Embryonic development: Protostome.
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.
38
Rotifera
● Key names: Rotifers.
● 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.
● Embryonic development: Protostome
General Characteristics: Not truly segmented,
can reproduce sexually or parthenogenetically,
mostly freshwater environments. Draw food and
water into mouth by beating cilia.
39
Annelida
● E.g. 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. One way digestion with gizzard
(mechanical digestion occurs here prior to
intestine).
● 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:
The first phyla to
develop segmentation. Segmented bodies, coelom
is divided by septa, sexual (hermaphrodites) and
asexual (regeneration) reproduction, longitudinal
and circular muscles.
40
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
41
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 is the most diverse phylum with the
highest number of different species.
42
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: Exoskeleton of chitin,
jointed appendages, three pairs of legs, more
species than any other phylum combined,
metamorphosis (distinct stages, altered
appearance as insect matures).
43
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 glands.
General Characteristics: Exoskeleton, jointed
appendages, four pairs of legs, terrestrial habitats.
44
Arthropoda (Crustacea)
● E.g. lobster, crayfish, crab.
● Respiratory system: some have gills.
● Excretory system: Green glands (aquatic),
malpighian tubules (terrestrial).
General Characteristics: Exoskeleton, jointed
appendages, aquatic and terrestrial habitats.
45
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: Tube feet (suction cups
for walking and obtaining food), sexual or asexual
reproduction, closest related major phyla to
chordates.
46
Chordates (most important to know)
● E.g. Vertebrates.
● Body Symmetry: Bilateral.
● Tissue Organization: Triploblasts, eumetazoa.
● Embryonic Development: Deuterostome.
47
What are the shared structures of chordates?
1) notochord
2) dorsal hollow nerve cord
3) pharyngeal gill slits
4) muscular post-anal tail
Mnemonic: Do Not Pinch People
D = Dorsal hollow nerve cord
N = Notochord
P = Pharyngeal gill slits
P = muscular Post-anal tail
48
Notochord
- cartilaginous rod derived from mesoderm. Forms the primitive axis and
supports the body during embryonic development. Develops into the spinal bones (not spinal cord).
49
Dorsal Hollow Nerve Cord:
- forms spinal cord -
basis of nervous system and brain.
50
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.
51
Muscular post-anal tail
- lost during
embryonic development in humans and many
other chordates
52
Types of Chordates
1) Lancelets (also known as Amphioxus)
2)Tunicates (also known as Urochordata)
3)Fish (Jawless):
4)Fish (Cartilaginous):
5)Fish (Bony):
6)Amphibia:
7)Mammalia (Monotremes):
8)Mammalia (Placental):
9)Reptilia:
10) Birds
53
Lancelets (also known as Amphioxus):
● Subphylum: Cephalochordata.
● Circulatory system: Closed circulatory
system, lacks heart, contains contractile
blood vessels.
● Respiratory system: Diffusion (body wall).
● General characteristics: Keep all the
same developmental characteristics as
other chordates, but lack vertebrae.
54
Tunicates (also known as Urochordata):
● 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.
55
Fish (Jawless):
● E.g. Agnatha, lamprey, hagfish.
● Subphylum: Vertebrata.
● Circulatory system: Two-chambered
heart.
● Respiratory system: Gills, countercurrent
exchange.
56
Fish (Cartilaginous):
● E.g. Shark.
● Subphylum: Vertebrata.
● Circulatory system: Two-chambered
heart.
● Respiratory system: Gills.
● General characteristics: Jaws and teeth.
Classified as chondrichthyes (skeletons
made of cartilage).
57
Fish (Bony):
● E.g. Salmon, halibut.
● Subphylum: Vertebrata.
● Circulatory system: Two-chambered
heart.
● Respiratory system: Gills.
● General characteristics: Bony skeleton.
Classified as osteichthyes (skeleton made
of bone tissue). Includes ray-finned fish
(actinopterygii) and lobe-finned fish
(sarcopterygii).
58
Amphibia:
● 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. Frogs and toads lose tails.
59
Mammalia (Monotremes):
● E.g. Duckbill platypus, spiny anteater.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered
heart.
● Respiratory system: Lungs.
60
Mammalia (Placental):
● E.g. Bat, whale, mouse, human.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered
heart.
● Respiratory system: Lungs.
● General characteristics: homeotherms (an organism that maintains its body temperature at a constant level, usually above that of the environment, by its metabolic activity.),
placenta supports fetus.
61
Reptilia:
● 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: Internal
fertilization, cold blooded
(poikilothermic).
62
Birds:
● E.g. Eagle, blue jay.
● Subphylum: Vertebrata.
● Circulatory system: Four-chambered
heart.
● Respiratory system: Lungs.
● General characteristics: Eggs in shells.
63
Summary of Prokaryotes vs Eukaryotes
****Refer to page 65 of DAT bootcamp****
