module 1 - diversity of life (exam 1) Flashcards
1
Q
what were early forms of classifying organisms?
A
noting similar features
animal/vegetable/mineral characteristics
microscopes to see microorganisms
identifying kingdoms (prokaryotes vs eukaryotes)
2
Q
early classifications of organisms were largely based on _______ features
A
morphological
3
Q
genetics were an important for understanding ________ when it came to classifications
A
understanding similarity between and among organisms
4
Q
DNA is the material of _____ and is common to _____ organisms
A
inheritance, all
5
Q
we resemble our relatives because we share many _____
A
alleles (specific versions of genes)
6
Q
the most accurate measure of “relatedness” is….
A
how similar genomes are
7
Q
the first widely compared genetic sequences were… because…
A
ribosomal RNA (rRNA)
because ribosomes must function in all living organisms and their sequences are short and evolve slowly
8
Q
the three types of organisms are…
A
bacteria, archaea, eukarya
9
Q
T or F: archaea is more closely related to bacteria than eukarya
A
false
archaea is more closely related to eukarya than bacteria
10
Q
there are evolutionary remnants of bacteria present in today’s eukaryotes, such as ____ and ____
A
mitochondria and chloroplasts
11
Q
what was one of the biggest clues that archaea were more closely related to eukarya than bacteria?
A
archaea and eukarya share similar ribosomal sensitivity to different drugs
12
Q
what is gram staining?
A
process of dying microscopic bacteria in order to classify them
13
Q
how does gram staining work?
A
gram dye easily binds to peptidoglycan, the makeup of the cell wall of some bacteria (these bacteria show up purple and are gram positive). bacteria that have an outer lipid bilayer instead of a peptidoglycan cell wall show up as pink and are gram negative since the dye cannot bind to their outer layer.
14
Q
gram staining is useful for _____ of bacteria but not for creating ______
A
identification, phylogenies
15
Q
what are the three shape types of bacteria?
A
spheres, rods, and spirals
(coccus, bacillus, helix)
16
Q
how do bacteria move?
A
flagella, twisting, or gliding
17
Q
how do bacteria communicate with each other?
A
via chemicals or light
18
Q
how do bacteria reproduce?
A
asexually (fission)
19
Q
what is horizontal (lateral) gene transfer?
A
between two already existing individuals, one picks up DNA from another (they don’t have to be closely related)
can complicate using sequences to determine phylogenies
20
Q
what is vertical gene transfer?
A
DNA transfer generation to generation (like in multicellular organisms)
21
Q
what are the three types of DNA transfer?
A
conjugation, transformation, transduction
22
Q
describe DNA transfer by conjugation
A
DNA (usually a plasmid) from a donor cell is transferred through a pilus into the recipient cell (2 live organisms)
23
Q
describe DNA transfer by transformation
A
DNA is released into the environment by dead cell(s) is taken up by a live recipient cell
24
Q
describe DNA transfer by transduction
A
DNA is transferred from a virus-infected donor to a recipient cell by the virus
25
what are obligate anaerobes?
organisms that oxygen is poisonous to (live in oxygen-free environments)
26
what are obligate aerobes?
prokaryotes that require oxygen
27
what are facultative anaerobes?
prokaryotes that can use either aerobic or anaerobic respiration
28
define photoautotrophs
organisms that convert light energy into sugars for themselves
29
who is responsible for converting earth's atmosphere to aerobic?
photoautotrophs - O2 is a byproduct
30
define photoheterotrophs
organisms that harvest energy from light but rely on sugars made by other organisms
31
define chemoheterotrophs
organisms that feed on other organisms
32
define decomposers & how they work
organisms that break down dead bodies
return carbon to soil and the atmosphere (CO2)
33
define nitrogen fixers & why they're necessary
convert N2 from atmosphere to NH3
NH3 is used by other organisms to make amino acids
34
the human body harbors how many times more bacteria than human cells?
4x
35
how do pathogens cause diseases? (4)
invade the body
evade immune system
multiply
produce toxins (main problem)
36
define endotoxins & exotoxins (in pathogens)
endo: host is exposed to these toxins when the bacteria is lysed (broken down) - results in fever, vomiting, diarrhea, etc.
exo: toxins are released by living bacteria - can be highly poisonous or fatal
37
how are viruses classified?
based on their nucleic acid type - RNA or DNA
38
what are the 4 types of viruses?
positive sense RNA
negative sense RNA
RNA retrovirus
DNA virus
39
give characteristics of a positive sense RNA virus (2)
the genome is the template for translation
RNA genome balled up in middle of virus allows for replication for further virus synthesis
40
give characteristics of a negative sense RNA virus (2)
RNA genome is NOT template for translation, but rather its complement
an enzyme creates the complementary RNA strand, which is the template for translation
41
what is the enzyme that produces the complementary strand for translation of a negative sense RNA virus?
(viral-encoded) RNA-dependent RNA polymerase
42
give characteristics of an RNA retrovirus (4 + ex.)
utilizes reverse transcriptase (RNA --> DNA)
proviral DNA is integrated into host's genome
specific to vertebrate animals
winds up in host's chromosomes
ex. HIV
43
give characteristics of a DNA virus (2)
genome = DNA
includes bacteriophages (viruses that infect bacteria)
44
what are the features of eukaryotes? (2)
organized, membrane-bound nucleus with linear chromosomes
membrane bound organelles such as mitochondria, chloroplasts, and digestive vacuoles
45
movement of a eukaryote relies on the ______
cytoskeleton
necessary for predation, changing shape, and increasing size
46
chloroplasts and mitochondria (energy metabolizers) presumably have origins of _____
free-living bacteria
47
eukaryotes have _______ DNA molecules with _________ of replication
these molecules carry many ______ and ________ regions
linear
multiple origins
genes, regulatory
48
all eukaryotes have a _______ life cycle (except rotifers)
sexual
49
how are opisthokonts characterized?
what kinds of eukaryotes do they include?
flagellum is posterior, single
includes multicellular animals, uni or multicellular fungi, and choanoflagellates
50
give characteristics of fungi (5)
cell wall of chitin
can be multi or unicellular (ex. yeast)
have absorptive heterotrophy (enzymes are secreted to break down food and then they're reabsorbed b/c fungi don't have internal digestive systems)
can feed on living and dead organisms
animals and fungi are very closely related
51
how are amoebozoans characterized? (4)
give examples of them
use pseudopods for motility
aquatic (fresh water)
eat via phagocytosis
predator, scavenger, or parasite
ex. physarum and dictyostelium
52
define characteristics of physarum (amoebozoans) (5)
a plasmodial slime mold
terrestrial (forests)
disperse, then aggregate to form fruiting bodies where spores form by meiosis
scavengers, ingest by endocytosis
move by cytoplasmic streaming
53
define characteristics of dictyostelium (amoebozoans) (3)
a cellular slime mold
amoeba-like single cells aggregate into a "slug" when dry or starved
cells are retained and form spores
54
how are rhizarians characterized? (3)
give examples of them
unicellular
aquatic
long pseudopods
ex. foraminiferans and radiolarians
55
define characteristics of foraminiferans (rhizarians) (3)
external shells of calcium carbonate
source of limestone
pseudobods ensnare plankton
56
define characteristics of radiolarians (rhizarians) (3)
glassy endoskeletons (rigid material inside cell)
include some of the largest unicellular eukaryotes
can have photosynthetic endosymbionts-dinoflagellates
57
how are archaeplastids characterized? (1)
give examples of them
multicellular land plants
ex. red algae, green algae
58
define characteristics of red algae (archaeplastids) (2)
marine
photosynthetic using chlorophyll a and phycoerythrin (a red protein-pigment)
59
define characteristics and examples of green algae (2)
use chlorophyll a and b (like land plants)
can be uni or multicellular
ex. volvox (freshwater spheres of flagellated cells)
ex. sea lettuce (marine)
60
how are stramenopiles characterized? (1)
give examples of them
have unequal flagella
ex. diatoms and brown algae
61
T or F: all types of algae are related
false
62
define characteristics of diatoms (stramenopiles) (5)
single-celled
silica in cells walls - upper and lower like a petri dish
found in fresh and salt water
photosynthetic-storage produces oils
used for diatomaceous earth-filtration
63
define characteristics and examples of brown algae (4)
can be multicellular
photosynthetic - chlorophyll a & c + brown pigments
source of emulsifiers of ice cream
ex. sea palms & giant kelp
64
what is endosymbiosis?
when a prokaryote engulfs another
origination of chloroplasts and mitrochondria
65
what were the first clues of endosymbiosis (for chloroplasts)?
there is more than one membrane surrounding chloroplasts
66
how are alveolates characterized? (2)
give examples of them
single celled
have sacs under cell membrane
ex. ciliates, dinoflagellates and apicomplexans
67
define characteristics of ciliates (paramecium) (alveolates) (3)
body covered with cilia (motility)
fresh water
sex: equal exchange of nuclei
68
define characteristics of apicomplexans (plasmodium) (alveolates) (3)
parasite causing malaria
life cycle in mosquitoes (human blood)
has nonfunctional chloroplasts
69
how are excavates characterized? (3)
give examples
unicellular
often lack mitochondria
named for surface groove
ex. giardia (a diplomonad), euglena (a euglenid), and trypanosome (a kinetoplastid)
70
define characteristics of giardia (excavate) (4)
a diplomonad
has many flagella
lacks mitochondria
freshwater - parasite causing giardiasis
71
define characteristics of euglena (excavate) (3)
a euglenid
photosynthetic if in the dark
anterior flagellum
72
define characteristics of trypanosomes (excavate) (2)
a kinetoplastid
parasite causing sleeping sickness
73
what defines an animal? (4)
multicellular (cells adhere after mitotic division and can communicate with each other)
heterotrophic (eat other organisms)
internal digestion (vs fungi)
have motility (muscles, nerves, skeleton)
74
animals are phylogenetically ________ and have a common __________
monophyletic, ancestor
75
the common ancestor of animals is thought to resemble ___________
colonial choanoflagellates
76
the earliest and simplest animals are ________-
marine
77
define characteristics of sponges (4)
lack tissues (groups of similar cells acting as one)
body is cup-shaped
inner surface is composed of choanocytes (flagella beat to draw water through pores into central cavity)
lots of pores
78
what characterizes dipoblastic animals? (5)
give examples
2 body layers
distinct organ systems
central gastrovascular cavity (1 hole for mouth & anus)
noncentralized nerve net (no brain)
aquatic - body supported by water
ex. ctenophores (comb jellies)
ex. cnidarians (jelly fish, corals)
79
what are the 2 main differences between jelly fish & comb jellies vs more complex animals?
jelly fish/comb jellies have only 2 body layers in embryo and have radial symmetry
where more complex animals have 3 embryonic layers and bilateral symmetry
80
deuterostomes and protostomes are both characterized by ________
what are the characterizations?
early embryonic development
deutero: anus formed before mouth
proto: mouth formed before anus
81
most animals are _______ (invertebrates or vertebrates)
invertebrates (no backbone)
82
what are the 3 major animal clades?
lophotrochozoans
ecdysozoans
deuterostomes
83
what are the most successful types of animals & how many of them are there on earth?
arthropods
10^18 present on earth
84
how are lophotrochozoans characterized? (2)
give examples of them
common larval form & a feeding apparatus
bryzoans, molluscs, and annelids
85
how are ecdysozoans characterized? (1)
give examples of them
shed their exoskeleton to grow
arthropods and nemotodes
86
how are deuterostomes characterized? (1)
give examples of them
mouth forms second (after anus)
echinoderms, hemichordates, vertebrates
87
arthropod means:
"joint" and "limb"
88
which types of animal are the most complex of the ecdysozoans?
arthropods
89
what are characteristics of arthropods? (3)
give examples of them
body is supported by an exoskeleton of chitin (serves as both skeleton and skin)
a segmented body plan (metameric - repeated segments of a body & legs - like a centipede)
paired & jointed appendages
ex. crustaceans (lobster), hexapods (grasshopper), myriapods (millipede), chelicerates (horseshoe crab, spiders)
90
what are the two other types of ecdysozoans besides arthropods?
give characteristics of them
tardigrades: limbs not jointed, can shrink up for up to a decade when they get too dry
nematodes: no limbs at all, no segmentation, scavengers, predators, or parasites (ex. round worm)
91
define characteristics of lophotrochozoans (1)
give examples of them
have a lophophore (feeding structure) and a trochophore (free-living larval stage)
ex. molluscs, annelids, flatworms, rotifers, bryzoans
92
give characteristics of molluscs (lophotrochozoan) (3)
give examples
have a foot (locomotion)
internal organs
mantle - secretes shell
ex. gastropods (snail), bivalves (clams), cephalopods (octopus)
93
give characteristics of annelids (lophotrochozoans) (1)
give examples
have segmented bodies
ex. earthworms, leeches
94
give characteristics of flatworms (lophotrochozoans) (2)
give examples
most are internal parasites
simple bodies - often lack digestive tracts
ex. flukes, tapeworms
95
give characteristics of rotifers (lophotrochozoans) (2)
have a ciliated corona (sweeps food into mouth)
some species are only female
96
give characteristics of bryozoans (lophotrochozoans) (1)
colonial organisms
97
what is the difference between radial and bilateral symmetry?
radial: any plane along the main body axis divides the animal into similar halves
bilateral: only a single plane through the anterior-posterior divides the animal into mirror image halves
98
give characteristics of echinoderms (3)
most are radially symmetric as adults
larvae are bilaterally symmetric
move and feed using "tube feet" - can attach to surfaces and/or food
99
give characteristics of chordates (4)
give examples of them
have a dorsal, hollow nerve cord (like a spinal cord)
postanal tail for locomotion
have a notochord for flexible support (embryonic only in some)
pharyngeal slits for gas exchange
examples: lancelets, tunicates, and vertebrates
100
half of all vertebrate species (~27,000) are what?
what is significant about them?
ray-finned fish
they posses jaws - one of the first important innovations
101
give characteristics of jawed fishes (2)
give examples
can be either cartilaginous or bony
lobe-fins
examples: sharks, rays
102
what are the most primitive tetrapods?
give characteristics (3) and examples of them
amphibians
have moist skin, require water for eggs (no shell), and require wet habitats
examples: frogs, salamanders, caecilians (limbs lost in adulthood)
103
what are some of the vertebrate innovations? (6)
an internal skeleton
primarily bone instead of cartilage
jointed fins
nares (nose-like thing for breathing air)
terrestrial limbs
amniotic eggs to withstand drying conditions
104
what is the most important vertebrate innovation?
amniotic eggs to withstand drying conditions
105
amniotes include which types of animals?
reptiles and mammals
106
give characteristics of reptiles (2)
give examples
amniotic egg provides "private pond" to keep moist during development
have scales (keratin vs bone-derived scales of fish)
examples: turtles, tuataras, squamates (snakes/lizards), crocodilians, dinosaurs
107
give characteristics of mammals (5)
give examples
mammary glands
sweat glands
4-chambered heart
hair
varying types of teeth
examples: prototherians (lay eggs), marsupials (newborns move to pouch), and eutherians (more developed at birth)
108
what are the two types of cellularity in plants
colonial organisms - multiple cells adhere but are not differentiated (1 type of cell in entire organism)
multicellular - more than one cell type
109
what are the differences & similarities of all green plants vs only land plants?
all green plants: chlorophyll a and b, starch for storage, cellulose in cell walls
only land plants: spores, apical meristem-localized growth, plasmodesmata (cell communication)
110
what are the advantageous innovations of land plants? (5)
vascular tissue - cells specialized for transport of fluids allow increased growth and size
leaves - specialized organ for photosynthesis
roots - uptake of water and minerals
seeds - next generation dispersed with food (give offspring inc. chance of survival)
flowers - pollinators enable wide crossing, which increases diversity
111
all land plants have what kind of reproduction system?
what does it consist of?
alternation of generations - separate, multicellular bodies that perform either fertilization or meiosis
sporophyte and gametophyte
112
explain a sporophyte
produces cells that undergo meiosis
in diploid (2n) stage
Fertilization --> zygote --> mitosis --> multicellular sporophyte --> meiosis
113
explain a gametophyte
produces gametes (n)
develops from spores after meiosis
meiosis --> spore --> mitosis --> multicellular gametophyte --> mitosis --> gametes --> fertilization
114
nonvascular plants have a dominant ________ (sporophyte or gametophyte)?
dominant gametophyte - plants are mostly green and for a long time
115
what are characteristics of nonvascular plants? (4)
give examples of them
gametophyte green for a long time
sporophyte only briefly green & dependent of gametophyte for nutrition
small & live in moist environments
gametophyte has simple body: few cell types, few cells thick, lacks seeds, lacks leaves/stems/roots, lacks vascular tissue
examples: mosses, liverworts, hornworts
116
give characteristics of vascular plants (4)
water-conducting cell in the xylem (tracheids) conduct water over long distances, which allows great size & structural support
dominant sporophyte
most have true roots
some reproduce using seeds
117
give characteristics of FIRST vascular plants
stem only
no leaves, no roots (held up by rhizoids - underground stem)
stem branches at tip for equal dichotomous branching
reproduce by producing spores in sporangia
118
how did the first vascular plants grow with no leaves?
stems photosynthetic
119
leaves have evolved at least twice - what are the 2 origins?
1) microphylls - small leaves, flattened, sterile sporangia
2) megaphylls - fusions of side branches, flat plates of photosynthetic tissue developed between branches
120
give characteristics of lycophytes (6)
"club mosses" but not a moss
microphylls
dichotomous branching
spores produced in sporangia in strobilus (no seeds)
uncommon now
primary parent material for coal
121
give examples and characteristics of ferns
don't produce seeds
ex. horsetail: unbranched stem, small leaves in whorls
ex. whisk ferns: no leaves, no roots, dichotomous branching, evolved from ancestor with leaves and roots
ex. ferns: most diverse, have true leaves & roots, both gametophyte and sporophyte are green & photosynthetic
122
why are seeds useful for reproduction? (2)
they protect and nourish embryo (stored nutrients b/c no photosynthesis)
allow survival through unfavorable conditions
123
what types of plants are the most successful?
seed plants - >80% biomass
124
are seed plants vascular or nonvascular
vascular (trees come from seeds)
125
what are the two types of seed plants?
gymnosperms and angiosperms
126
what is the main characteristic of gymnosperms
give examples of them
seeds contained in cones, not flowers
ex. cycads, gnetales, ginkgo, conifers
127
give characteristics of angiosperms (5)
seeds produced inside an ovary (covered part of a flower)
most diverse, successful, and highly evolved
economically important for food, fiber, building materials, and drugs
animal pollinators like attractive flowers
flowers are most useful for identification
128
give characteristics of monocots (angiosperms) (5)
one cotyledon
parallel veins in leaves
vascular bundles complexly arranged
fibrous root system
floral parts usually in multiples of 3
129
give characteristics of eudicots (5)
two cotyledons
veins in leaves usually netlike
vascular bundles arranged in a ring
taproot usually present
floral parts usually in multiples of 4 or 5
