Lab Exam Flashcards
1
Q
What is the Field of view (FOV)?
A
entire area (seen as a circle) observed through the ocular lens
2
Q
What is the FOV in micrometers for all 4 types of lenses?
A
1) scanning objective lens: 5000 micrometers
2) low-power objective lens: 2000 micrometers
3) high-power objective lens: 500 micrometers
4) oil immersion: 200 micrometers
3
Q
What does N.A., or numerical aperture which is written on each objective lens, signal?
A
N.A. signals the resolving power of each lens
4
Q
What are the 2 functions of the objective lenses?
A
1) magnify
2) improve resolving power of the scope
5
Q
What is resolution?
A
the minimum amount of distance between 2 points that can still be resolved (not blurry)
6
Q
What is the formula for resolution?
A
d = 0.5(lambda)/nsin(theta)
7
Q
What is N.A. in the formula for resolution?
A
nsin(theta)
8
Q
What 2 things does the condenser strongly impact?
A
it strongly impacts the resolution power of the microscope and the depth of field of the specimen
9
Q
why do we use a series of low-power lenses instead of one large convex lens?
A
because any aberrations in the lens will strongly impact the resolving power of the microscope and larger lenses are more likely to get aberrations in them
10
Q
What is the function of the condenser?
A
converge the rays of light received from the circle of light passing through the aperture iris diaphragm and bend them into a cone of light that strikes the specimen
11
Q
What is refraction?
A
the change in direction of the light due to change in velocity as it passes through different density medium
12
Q
what’s the working distance?
A
distance between the objective lens and the specimen on the stage
13
Q
What does the koehler illumination protocol do?
A
Ensures that the rays of light within the second inverted cone, created as the light passes through the specimen, enter directly into the objective lens. THEREFORE, it lines up the condenser with the objective lens
14
Q
What 2 things does koehler illumination optimize?
A
1) resolution
2) contrast
15
Q
What does parfocal mean?
A
microscopes that keeps the image in focus as you move from the scanning to high power objective lens: working distance is automatically adjusted
16
Q
Why does oil immersion provide the highest resolving power?
A
they have the same refractive index which prevents the rays of light from refracting away from the reach of the objective lens
17
Q
How does dark-field illumination work?
A
condenser unit is fitted with a dark-field stop (spider-light stop) which creates a hollow cone of light. Then an inverted hollow cone of light then emerges above the slide where only light refracted by the specimen enters the objective lens = background is black and only distinct features of the specimen are illuminated
18
Q
What is dark field illumination good for?
A
good for viewing tiny live organisms and bacterial motion
19
Q
What is a downside of dark field illumination?
A
can see live organisms, but it cooks them
20
Q
What are 6 examples of important protistan photoautotrophs?
A
1) dinoflagellates
2) diatoms
3) volvox
4) brown algae
5) euglena (mixotroph)
6) spirogyra (charophytes)
21
Q
What do most triploblastic animals have?
A
a fluid-filled body cavity called a coelom
22
Q
During embryonic development of coelomates, how are the germ layers arranged?
A
mesoderm covers both ectoderm and endoderm creating a cavity that’s entirely lined by mesoderm tissue
23
Q
During embryonic development of pseudocoelomates, how are the germ layers arranged?
A
mesoderm only covers the ectoderm
24
Q
What are the 2 functions of the coelom?
A
1) protects organs against injury
2) allows organs to move independently from the rest of the body
25
What are triploblastic animals that lack coeloms called?
acoelomates
26
What is the cavity of acoelomates filled with?
filed with cells derived from the mesoderm
27
What are the 4 kinds of tissues that all animals have?
1) epithelial
2) connective
3) muscle
4) nervous
28
What 2 tissues are unique to animals?
muscle and nervous tissue
29
In the porifera phylum, what are sponges closely related to?
choanoflagellates - a colonial protist with a posterior flagellum
30
what are the 4 features that sponges lack that makes them get categorized as metazoans instead of eumetazoans?
1) lack true tissue
2) Haphazard organization of cells
3) lack hox genes
4) no symmetry
31
What are the 4 reasons why sponges made the cut as metazoans instead of being categorized as protists?
1) multicellular
2) heterotrophic
3) no cell wall
4) produce sperm cells
32
What are the 2 cnidarian clades?
1) medusozoan = produce medusa (jelly-fish)
2) anthozoa = polyps
33
Are cnidarians diplo or triplo?
diplo = mostly epithelial animals
34
What are the 2 functions of mesoglea (connective tissue) in cnidarians?
1) anchors the gastrodermis and epidermis in the cnidarian
2) contributes to buoyancy in medusa
35
Where is food digested in cnidarians?
gastrovascular cavity
36
how are gonads, muscle cells and nerve cells made in cnidarians?
epithelial cells from the endoderm migrate to the mesoglea and differentiate into gonads, muscle and nerve cells
37
What animals do muscle and nervous tissue have their origins in?
cnidarians
38
What is a specialized cell of the epidermis in cnidarians?
cnidocytes that function in stinging prey
39
what is contained within cnidocytes?
nematocytes - a thread-like organelle that contains venom
40
True or false: all bilaterians are triploblastic?
TRUE
41
Are flatworms (platyhelminthes) diplo or triplo?
triplo = bilateral
42
Do flatworms have a coelom?
NO: they are acoelomates meaning the mesoderm tissue fills the entire inside of the animal
43
What are 3 distinguishing features of flatworms?
1) unsegmented
2) dorsoventrally flattened
3) single opening leading to the gastrovascular cavity
44
What do we start to see with the Platyhelminthes phylum; what does this consist of?
compartmentalization:
mouth and pharynx leading to gastrovascular cavity and a protonephridium for osmoregulation and waste elimination
45
What 2 things do planarians (flatworm) have in particular?
1) a complex nervous system derived from ectoderm
2) well developed muscle tissue
46
What does the complex nervous system of planarians (flatworm) consist of?
1) light-sensitive eyespots
2) centralized nerve nets
47
What does the muscle tissue of planarians consist of?
1) circular muscles
2) longitudinal muscles
3) dorsoventral muscles
48
What are 3 traits of rotifers?
1) small - often smaller than protists
2) complete digestive tract (mouth and anus)
3) fluid filled pseudocoelom
49
What is the pseudocoelom of rotifers akin to and why?
It's akin to a circulatory system of more complex animals since body movements moves the fluid in it around to help distribute nutrients
50
What is the distinguishing feature of the rotifer?
Crown of cilia around the mouth that draws in water like a vortex
51
What are 4 traits of annelids?
1) true coelomates
2) segmented bodies
3) complete digestive system
4 closed circulatory system
52
What functions in locomotion and gas exchange in annelids?
parapodia - paddle-like structures on each body segment, each with stiff bristles made of chitin called chaetae: blood vessels in parapodia function as gills
53
Which of the annelids has the most highly compartmentalized alimentary canal?
earthworms
54
what are the 7 components of the highly compartmentalized alimentary canal of the earthworm?
1) mouth
2) pharynx
3) esophagus
4) crop
5) gizzard
6) intestines
7) anus
55
What partitions each segment in earthworms?
septa
56
What 2 other components are present in or on each segment of earthworms?
1) 4 pairs of chaetae for locomotion
2) metanephridium derived from mesoderm in association with blood vessels
57
What muscles do annelids have?
1) circular muscles
2) longitudinal muscles
58
What are 4 traits of nematodes?
1) pseudocoelomates (nicely observed under microscope)
2) complete digestive system
3) lack circulatory and respiratory system
4) muscles aligned longitudinally limiting their motion to thrashing left and right (no circular muscles)
59
what occurs to nutrients in nematodes after they've been absorbed by the digestive system?
the nutrients circulate the hemolymph
60
What is the symmetry of echinoderms?
most adults: radial symmetry with multiples of 5
larvae: bilateral
61
What are 4 traits of echinoderms?
1) coelomates
2) complete digestive tracts (they're short)
3) digestive glands
4) water vascular system for feeding and locomotion
62
How does water flow in and out of the water vascular system of echinoderms?
through the madreporite located on the aboral surface (top surface)
63
what else occurs on the aboral surface of echinoderms?
gills functioning in gas exchange
64
What 2 things occur on the oral surface of the echinoderm?
1) mouth
2) tube feet lining the length of the arms of a sea star
65
What is the most distinct feature of chitons?
8 calcareous plates
66
What are 4 other traits of chitons?
1) bilateral
2) radula to scrape algae off of rocks that is reinforced with iron oxides
3) gill filaments lining either side of the foot
4) gills sheltered within mantle cavity
67
What are 4 animals included in gastropods?
1) snails
2) slugs
3) limpets
4) sea slugs
68
What kind of shell do gastropods have?
single spiralled shell
69
What is a distinct feature of gastropods that can only be seen when dissecting the animal?
torsion occurring during embryonic development which puts the anus to an anterior position above the head
70
What is a defining feature of gastropods?
well developed heads (second to cephalopods) that includes a pair of eyes and tentacles
71
how can one identify snails at a species level?
looking at the teeth lining the radula
72
What are 4 animals contained in the bivalve taxa?
1) oysters
2) clams
3) scallops
4) mussels
73
What is a distinct characteristic of bivalves that can be seen just by looking at them?
they have a pair of laterally compressed shells (called valves) held together by strong adductor muscles
74
Where are the gills found in bivalves and what are their 2 functions?
in the mantle cavity and they function in filter feeding and gas exchange
75
How do bivalves get food to their mouth?
water with suspended food enters the incurrent siphon. The food that gets trapped in the mucous of film of the gills is moved toward the mouth by beating cilia = NO RADULA
76
What 3 things exit through the excurrent siphon in bivalves?
1) water
2) suspended wastes
3) gametes
77
How do bivalves move?
most species are sedentary, but some have limited mobility with a laterally compressed foot used for digging and anchoring
78
what are 4 animals contained in the cephalopod taxa?
1) squid
2) cuttlefish
3) octopus
4) nautilus
79
What is the foot of cephalopods modified into?
arms
80
What is the mantle of cephalopods modified into?
excurrent siphon to forcefully eject water allowing for jet propulsion
81
What is the difference between octopi, squid and cuttlefish, and the nautilus?
Octopi = 8 arms with suckers
squid and cuttlefish = 8 arms and 2 tentacles specialized for catching prey
Nautilus = shelled representative with >90 arms without suckers
82
What are the 3 sub-phyla in Arthropoda phylum?
1) Chelicerates
2) Myriapods
3) Pancrustaceans = crustaceans and hexapods
83
What are 6 animals in the chelicerates sub-phylum?
1) ticks
2) mites
3) spiders
4) scorpions
5) horseshoe crabs
6) sea spiders
84
What does the body of a chelicerate look like?
1) 2 body segments = cephalothorax and posterior abdomen
2) chelicerae = most anterior appendage for gripping food NOT EATING
3) Pedipalps posterior to the chelicerae
4) 4 pairs of walking appendages
85
Overall, how many paired appendages do chelicerae have?
6 paired appendages = 4 for walking, chelicerae and pedipalps
86
What is the key feature of chelicerates?
Chelicerae
87
What do chelicerae function in spiders?
they're hollow and function in injecting prey with venom
88
What are the most anterior appendages of both pancrustaceans and myriapods?
antennae and mandibles
89
what is the function of antennae?
function as sense organs
90
what is the function of mandibles?
chewing, biting, and holding food
91
what are the 2 lineages in myriapods?
1) millipedes
2) centipedes
92
how many paired walking appendages do millipedes and centipedes have?
millipedes: 2 paired walking appendages per segment
centipedes: one pair of walking appendages per segment
93
which sub-phylum in arthropoda is the most successful and why?
pancrustaceans because it includes hexapods
94
What 4 animals are included in crustaceans?
1) isopods
2) decapods
3) copepods
4) barnacles
95
What feature is unique to crustaceans?
2 paired antennas in the most anterior position of their body
96
how many segments do crustaceans have?
3 = head, thorax, and abdomen
97
what appendages are included on the thorax of crustaceans?
paired walking appendages
98
what appendages are included on the abdomen of crustaceans?
swimmerets
99
what are 3 defining features of copepods?
1) smallest crustacean
2) have a cephalothorax and lack appendages on their abdomen
3) thin exoskeleton that's transparent
100
what are 2 characteristics of both isopods and decapods?
1) hard exoskeletons
2) appendages on each of their 3 body segments
101
what is the chitinous exoskeleton of decapods hardened with?
CaCO3
102
what are 3 animals in decapods?
crabs, shrimps, and lobsters
103
what is a key giveaway that barnacles are crustaceans and not bivalves?
although they have laterally compressed calcified shells, they have paired appendages that emerge out of the shell
104
how many segments do hexapods have?
3 = head, thorax, and abdomen
105
how many appendages are located on the head of hexapods?
single pair of antennas followed by 3 pairs of eating appendages (including mandibles)
106
where are the walking appendages of hexapods located and how many are there?
3 pair of walking appendages found on the thorax
107
what does the cuticle of hexapods differentiate into?
2 pairs of wings
108
what are the 4 derived characteristics of the chordate phylum?
1) notochord
2) dorsal hollow nerve chord
3) pharyngeal slits/pouches
4) post anal tail
109
what are the 2 invertebrate chordates?
1) lancelets
2) tunicates
110
what are the functions of the pharyngeal slits in lancelets?
filter feeding
111
how do lancelets breath?
epidermally
112
what are the functions of the pharynx in tunicates?
the pharyngeal slits are found in the pharynx and function altogther in both gas exchnage and filter feeding
113
what does the pharynx of tunicates resemble?
basket or gauze as it increases in size in adults
114
which chordate is the only one to retain all derived chordate characters as adults?
lancelets
115
what are cyclostomes?
lampreys and hagfish - jawless vertebrates with mouths lined with keratin-derived teeth
116
what are 2 key features of lampreys?
1) pharynx is perforated with 7 circular gills slits
2) the gills slits are lined with muscles to help ventilate the gills when they stitch their rasping mouth to their prey
117
what are 3 features of hagfish?
1) single nostril which water is sucked in before flowing out through gills
2) dense network of capillaries beneath skin that function in gas exchange when the animal is buried in sediment
3) slime glands on either side of their body
118
what are gnathostomes?
animals with jaws
119
what are chrondrichthyans?
gnathostomes with a skeleton mostly made of cartilage
120
what 3 animals are included in chondrichthyans?
sharks, rays, and skates
121
how does water enter sharks?
1) moving: by brute force
2) not moving: spiracle
122
how many gill slits do sharks have?
5
123
What are osteichthyans?
animals with bony skeletons
124
what is the defining feature of ray-finned fish?
radially extending bones covered in a thin web of skin on their pectoral and pelvic fins
125
what protects and aids in ventilating the gills of ray-finned fish?
the operculum
126
what is the defining feature of lobe-finned fish?
rod-shaped bones surrounded by muscle on pelvic and pectoral fins used to swim and "walk" on underwater sediment
127
what are the 2 surviving lineages of lobe-finned fish?
1) coelacanths
2) lungfish
128
how do lungfish breath?
they have a bimodal respiration system using both lungs and gills for gas exchange
129
what chordate is the closest living relatives to tetrapods?
lungfish
130
what modification occurred to the pharyngeal pouches as life came onto land?
the 1st pharyngeal pouch became the eustachian tube leading to the middle ear: amphibians, reptiles and mammals all have pharyngeal pouches that develop into ears
131
what are 4 traits of tetrapods?
1) ears
2) limbs with digits
3) pelvic bone fused to the vertebrae
4) neck to allow independent movement of the head
132
what are caecilians?
limbless amphibians
133
what are salamanders?
amphibians with tails
134
what is an adaptation occurring in amniotes?
terrestrial adapted eggs
135
are all gametophytes of plants haploid and are all sporophytes of plants diploid?
YES
136
What is the defining feature of chytrids and when is it observed?
retention of the posterior flagellum observed on its gametes and spores (zoospores)
137
what is the body of chytrids described as and why?
thallus rather than mycelium as they do not form elaborate mycelia and instead have a few short filaments with root like structures rhizoids for anchoring
138
What are the 2 structures observed in the sporophyte phase of chytrids?
Zoosporangium/Mitosporangia = produces spores via mitosis
Resistant sporangium/Meiosporangia = produces haploid spores via meiosis
139
What are zoospores?
spores with flagella
140
What are the 3 key traits of zygomycetes?
1) coenocytic molds
2) septum develops only to section off the gametangium
3) sporangiophores: structure with sporangium and within that are spores
141
What are the most elaborate part of the mycelium in zygomycetes and is it asexual or sexual?
sporangiophores = asexual - most dominant life cycle
142
What is the sexual structure that zygomycetes form?
zygosporangium
143
what is the distinct feature of glomoromycetes and what does it do?
they produce a haustorium - a specialized terminal end of a hypha that pushes into the plasma membrane of cortical cells in plant roots and increases the rate of nutrient exchange with the plant
144
What life cycle is seen in glomoromycetes?
only asexual
145
What are 3 distinct features of ascomycetes?
1) asci
2) conidiophores
3) ascocarps
146
What is the structure for the asexual life cycle of ascomycetes?
Spores produced asexually (i.e. mitotically) are called conidia and are borne on specialized hyphal tips called conidiophores
147
What is the structure for the sexual life cycle of ascomycetes?
ascocarp in which asci are densely crowded in
148
What are the 3 types of ascocarps?
Cleistothecium = completely closed
perithecium = narrowly open
apothecium = fully open
149
A lichen is a symbiotic association between a photosynthetic microorganism (algae or cyanobacteria) and a fungus; what type of fungus is it usually?
ascomycete
150
What does the dikaryotic mycelium of basidiomycetes form when under the right conditions?
basidiocarps lined with basidia where karyogamy occurs
151
after karyogamy in basidiomycetes, what occurs?
meiosis follows to yield 4 basidiospores resting on top of tiny buds called sterigmata which sit on top of each basidium
152
where are basidiospores discharged from?
discharged when they're resting on top of the tiny buds called sterigmata which are on top of basidium
153
What are the 3 parts do all nonvascular sporophytes have?
1) foot
2) seta
3) capsule/sporangium
154
what part is unique to liverwort sporophytes and what does it do?
elaters which are cells that aid in the dispersal of spores
155
What's the function of the foot in nonvascular plant sporophytes?
absorbs nutrients from the gametophyte
156
what does the seta of nonvascular plant sporophytes do?
transfers nutrients to the sporangium/capsule
157
what does the capsule/sporangium of nonvascular sporophytes do?
uses nutrients to produce spores
158
how do liverworts reproduce asexually?
by fragmentation of the gametophyte into structures called gemmae cups
159
Why are liverworts thought to be the first nonvascular plant on land?
because they do not have stomata; still have pores, but they do not open and closed since they lack guard cells
160
What does the sporophyte of mosses include?
1) foot
2) seta/stalk
3) sporangium/capsule
4) peristome
161
what does the peristome of moss sporophytes do?
the peristome teeth respond to humidity, bending outward and opening the sporangium when the air is dry
162
What does the gametophyte of ferns (monilophytes) look like and what is it called?
It looks like a heart where the lower portion = antheridium and top portion = archegonium with rhizoids at the bottom for anchoring onto substrates. It's called a Prothallium
163
What are the 6 functions of parenchyma cells?
1) performs most metabolic activities
2) photosynthesis
3) storage
4) fleshy part of fruit
5) wound repair (callus)
6) ability to divide and differentiate into other plant cells
164
what is the function of collenchyma cells?
flexible support: growth without restriction
165
what are the 2 functions of sclerenchyma cells?
1) provide structural support in mature plant tissues
2) strengthens wood, nutshells, seed coats, and fibers
166
What are the 3 dyes used in gram stain technique in order?
1) crystal violet stain
2) lugol's idodine
3) safranin
167
what is the function of the iodine, alcohol and safranin?
the iodine binds to crystal violet to form a tight complex. The alcohol rinses this complex off of the gram -, but in gram +, the alcohol renders the pores impervious, trapping the complex in between the plasma membrane and layer of peptidoglycan. Lastly, the safranin colours the gram - pink
168
what is the pour plate technique?
requires a series of dilutions then they're mixed with warm agar and poured into petri dishes
169
what is the purpose of the pour plate technique?
by decreasing the concentration of bacteria through series of dilutions, and pouring it onto agar, we can work backwards to estimate the bacterial count of the original stock
170
what's the formula to calculate the original concentration of bacteria in the original stock solution?
CFU/ml = (# of colonies x dilution factor)/volume plated
171
what # of colonies is considered a reliable petri dish for inferring the original concentration of bacteria in the stock solution?
30 to 300 colonies
172
what is the streak plate technique?
a sterilized inoculation loop dipped in original stock solution and streaked onto the agar
173
What are the 3 antibiotics used to test lethality in lab 1?
1) tetramycin
2) erythromycin
3) penicillin
174
Which of the 3 antibiotics used to test lethality in lab 1 was most lethal to gram -?
tetramycin
175
Which of the 3 antibiotics used to test lethality in lab 1 was most lethal to gram +?
penecillin
176
Which of the 3 antibiotics used to test lethality in lab 1 was lipid-soluble, making it difficult for it to get through the outer membrane of gram -?
erythromycin
